Age-related Changes in Corneal Parameters in the Turkish Population: A Pentacam-based Study

Age-related Changes in Corneal Parameters in the Turkish Population: A Pentacam-based Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Age-related Changes in Corneal Parameters in the Turkish Population: A Pentacam-based Study Denizcan Özizmirliler, İsmet Durak This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7851657/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 15 You are reading this latest preprint version Abstract Purpose: To evaluate anterior and posterior corneal surfaces and anterior segment parameters in the Turkish population using Pentacam, and to analyze age-related changes. Methods: Corneal topographies of patients without ocular pathology, admitted to the Ophthalmology Outpatient Clinic of xxxx Faculty of Medicine, were retrospectively reviewed. Measurements included anterior and posterior keratometry (K1, K2, Kmean), astigmatism values and axes, radii of curvature (Rflat, Rsteep, Rmean), asphericity (Q value), thinnest corneal thickness, corneal volume, anterior chamber volume (ACV), and anterior chamber depth (ACD). Patients were divided into four groups: 3–19, 20–39, 40–59, and ≥60 years. Age-related variations in parameters were analyzed. Results: A total of 1202 eyes of 601 patients (49.1% male, 50.9% female; mean age 35.3 ± 23.1 years) were included. Significant differences were found in anterior K1 and Kmean among the 20–39, 40–59, and ≥60 groups, and in anterior K2 between the 20–39 group and both younger and older groups. Posterior K2 differed between the 3–19 and ≥60 groups. Anterior and posterior radii increased in the 20–39 group but declined later, whereas posterior Rsteep rose with age. With-the-rule astigmatism decreased on the anterior surface but increased posteriorly, while against-the-rule and oblique astigmatism rose with age. Corneal asphericity showed more negative Q values after 40 years. ACV, ACD, corneal volume, and thinnest corneal thickness decreased progressively with age. Conclusions: The Turkish cornea shows age-related changes, becoming more prolate with age, with astigmatism shifts and reductions in chamber and corneal volumes. Key Words: Cornea, Corneal Topography, Pentacam. Figures Figure 1 Figure 2 INTRODUCTION Corneal refractive power is determined by the parameters of the anterior and posterior corneal surfaces, along with corneal thickness. As with many other organs, aging leads to changes in corneal parameters. Understanding age-related changes in the cornea across different populations is essential for distinguishing between pathological and physiological alterations. Corneal parameters are crucial in evaluating ectatic corneal disorders, which are characterized by progressive structural deformation, and in determining the optimal treatment. Additionally, corneal thickness serve as an important parameter in the diagnosis of glaucoma. [ 1 ] A review of the literature reveals age-related changes in corneal thickness, corneal asphericity, as well as anterior and posterior astigmatism values and their axes across different populations. [ 2 – 6 ] Determining age-related changes in these parameters and understanding the overall shape of the cornea enhance the success of various ocular surgeries, particularly refractive surgery. Recognizing the influence of posterior corneal astigmatism on total corneal astigmatism has highlighted the importance of corneal parameters in calculating and implanting intraocular lens power during cataract surgery. [ 7 – 11 ] In cases where posterior corneal astigmatism cannot be directly measured, estimating PCA based on parameters such as age, sex, or other biometric factors may significantly reduce toric intraocular lens calculation errors. The aim of our study is to determine the anterior and posterior corneal surface parameters, as well as anterior segment parameters, in the Turkish population using the Pentacam (Oculus Optikgeräte GmbH, Wetzlar, Germany) topography device and to analyze the age-related variations in these parameters. MATERIALS AND METHODS A detailed refractive examination and biomicroscopic evaluation were performed on all patients who presented to the Ophthalmology Clinic of Dokuz Eylül University Faculty of Medicine. Uncorrected visual acuity and best-corrected visual acuity (BCVA) values were recorded. A routine fundus examination was conducted. Data from individuals who underwent corneal topography measurements using the high-resolution Scheimpflug imaging system, the Pentacam corneal topography device, and who had no detected pathology were analyzed. This study was approved by the Ethical Committee of Dokuz Eylül University Faculty of Medicine (2021/36 − 11) and was conducted in accordance with the ethical principles stated in the Declaration of Helsinki and local regulations. The inclusion criteria were defined as follows: completion of a comprehensive ophthalmologic examination, acquisition of corneal topography, being over the age of 3 years, and having no history of surgery or disease that could alter the anatomical structure of the cornea. The exclusion criteria included the presence of any ocular pathology other than refractive errors, a history of ocular disease, or a history of ocular surgery. Patients who met these criteria and presented to the clinic between October 1, 2021, and December 31, 2022, were included in the study. Each morning, the topography device was calibrated. Corneal topography measurements were conducted between 08:30 AM and 5:00 PM by two different technicians. The same protocol was followed for all patients during the scanning process. Patients were positioned with their chins resting on the chin rest and their foreheads on the forehead strap, ensuring that their heads were completely horizontal. The room lights were turned off during image acquisition. Before the scan, patients were instructed to blink several times to prevent aberrations caused by tear film irregularities and to focus on the target at the center of the blue fixation light. Measurements were automatically performed using the Pentacam corneal topography device once the image was properly focused and the corneal apex was correctly aligned. After all measurements, error margins were checked, and only the highest-quality image data were included in the study. Patients were categorized into four age groups: 3–19 years, 20–39 years, 40–59 years, and 60 years and above (60+). Corneal parameter values were analyzed according to these age groups, and age-related changes in these parameters were investigated. The keratometric values of the anterior and posterior corneal surfaces (K1, K2, and Kmean), astigmatism and its axes, the axes of the anterior and posterior corneal surfaces, radii of curvature (Rflat, Rsteep, Rmean), asphericity values (Q value), the thinnest value of the cornea, corneal volume, anterior chamber volume (ACV), anterior chamber depth (ACD), and ophthalmologic examination findings were retrospectively analyzed. STATISTICAL ANALYSIS The t-test was used to determine differences between gender groups. The normality of the data distribution across age groups was assessed. For variables that followed a normal distribution, variance analysis (ANOVA) was applied. Corneal parameters were analyzed according to age groups. In cases where a significant difference was found in these analyses, Bonferroni post hoc test was conducted for pairwise comparisons between groups. For variables that did not follow a normal distribution, the Kruskal-Wallis variance analysis was performed. In cases where a significant difference was detected, Dunn’s test was applied for pairwise comparisons. For normally distributed variables, results were presented as mean ± standard deviation (SD). For non-normally distributed variables, results were expressed as median (min, max). Categorical variables were summarized as frequencies and percentages. The relationships between numerical variables were assessed using Pearson’s correlation coefficient. The level of statistical significance was set at p < 0.05.All statistical analyses were performed using IBM-SPSS version 25.0. Pearson correlation analysis was performed to determine the relationship between the same parameters in the right and left eyes. All statistical analyses were conducted based on the right eye data. A significance level of p 0.75: Very strong correlation. [ 12 ] The results of these correlation analyses were interpreted based on the defined correlation strength categories, with statistical significance set at p < 0.01 . RESULTS A total of 601 patients (1202 eyes) were included in the study. The age of the cases ranged from 3 to 86 years, with a mean age of 35.25 ± 23.02 years. 295 patients (49.1%) were male, and 306 patients (50.9%) were female. The mean age of male patients was 35.99 ± 23.79 years (Range:4–85), while the mean age of female patients was 34.53 ± 22.27 years (Range:3–86). The difference in mean age between genders was not statistically significant (p = 0.436). The distribution of patients across age groups was as follows: 196 patients (32.61%) in the 3–19 years age group, 163 patients (27.12%) in the 20–39 years age group, 114 patients (18.97%) in the 40–59 years age group, 128 patients (21.30%) in the 60 + group. When examining the distribution of patients across age groups, no statistically significant difference was observed (p = 0.436). The average corneal parameters in males and females are shown in the Table 1 . Statistically, anterior K1, anterior K2, anterior Kmean, posterior K1, posterior K2, posterior Kmean, posterior Rflat, and posterior Rmean were found to be higher in females compared to males, whereas anterior Rflat, anterior Rsteep, and anterior Rmean were lower in females. (p < 0.001) No significant difference was observed in anterior and posterior astigmatism, posterior steep astigmatism axis, anterior and posterior asphericity, thinnest corneal point, corneal volume, and anterior chamber depth between males and females. Table 1 Average Pentacam Parameter Values by Gender Male (n = 295) Female (n = 306) Pentacam Parameters Mean Standard Deviation (SD) Mean Standard Deviation (SD) p-value Anterior K1-Flat (D) 42,47 1,50 43,05 1,42 p < 0.001 Anterior K2-Steep (D) 43,64 1,54 44,10 1,53 p < 0.001 Anterior Kmean(D) 43,05 1,46 43,57 1,43 p < 0.001 Anterior Rflat (mm) 7,96 0,29 7,85 0,26 p < 0.001 Anterior Rsteep (mm) 7,74 0,27 7,66 0,26 p < 0.001 Anterior Rmean (mm) 7,84 0,30 7,75 0,25 p < 0.001 Anterior Astigmatism (D) 1,18 0,88 1,06 0,69 0,066 Anterior Steep Astigmatism Axis (°) 91,31 36,81 85,03 31,73 0,025 Anterior Asphericity (Q) -0,33 0,13 -0,35 0,14 0,073 Posterior K1-Flat (D) -6,11 0,27 -6,20 0,23 p < 0.001 Posterior K2-Steep (D) -6,46 0,28 -6,52 0,27 p < 0.001 Posterior Kmean(D) -6,28 0,26 -6,35 0,24 p < 0.001 Posterior Rflat (mm) 6,55 0,30 6,46 0,24 p < 0.001 Posterior Rsteep (mm) 6,21 0,27 6,15 0,25 0,002 Posterior Rmean (mm) 6,38 0,26 6,31 0,23 p < 0.001 Posterior Astigmatism (D) 0,34 0,20 0,32 0,15 0,154 Posterior Steep Astigmatism Axis (°) 96,10 23,86 93,53 19,22 0,145 Posterior Asphericity (Q) -0,39 0,18 -0,39 0,17 0,601 Thinnest Corneal Point (µm) 549,94 36,93 545,98 33,26 0,168 Corneal Volume (mm³) 61,23 3,98 61,21 3,76 0,943 Anterior Chamber Volume (mm³) 170,85 44,42 163,13 43,53 0,032 Anterior Chamber Depth (mm) 3,06 0,46 3,04 0,52 0,572 The analysis of Pentacam parameters by age groups is shown in the Table 2 . The anterior K1-Flat (D) K2-Steep (D) and Kmean of the anterior corneal surface was analyzed for pairwise group comparisons. A statistically significant difference was observed between the 60 + group and both the 20–39 years group (p = 0.002) and the 40–59 years group (p = 0.022). However, no statistically significant difference was found between the other age groups. A statistically significant difference was observed between the 20–39 years group and both the 3–19 years group (p = 0.012) and the 60 years and above group (p = 0.020)for anterior K2-Steep (D). However, no statistically significant difference was found between the other age groups. For the anterior Kmean, a statistically significant difference was observed between the 60 + group and both the 20–39 years group (p = 0.006) and the 40–59 years group (p = 0.031). However, no statistically significant difference was found between the other age groups. Table 2 Analysis of Pentacam Parameters by Age Groups Pentacam Parameters 3–19 (n = 196) 20–39 (n = 163) 40–59 (n = 114) 60 years and above (n = 128) Mean Standard Deviation (SD) Mean Standard Deviation (SD) Mean Standard Deviation (SD) Mean Standard Deviation (SD) p-value Anterior K1-Flat (D) 42,83 1,37 42,52 1,46 42,59 1,50 43,14 1,62 0,002 Anterior K2-Steep (D) 44,09 1,45 43,59 1,53 43,63 1,60 44,12 1,60 0,001 Anterior Kmean(D) 43,45 1,36 43,06 1,45 43,10 1,47 43,63 1,57 0,002 Anterior Rflat (mm) 7,89 0,25 7,95 0,28 7,93 0,28 7,83 0,30 0,003 Anterior Rsteep (mm)) 7,66 0,25 7,75 0,27 7,75 0,28 7,66 0,28 0,001 Anterior Rmean (mm) 7,77 0,29 7,85 0,26 7,84 0,27 7,75 0,28 0,002 Anterior Astigmatism (D)* 1,10 (0.10; 4.20) 0,90 (0; 3.40) 0,70 (0.10; 5.30) 0,80 (0; 4.70) P < 0,001 Anterior Steep Astigmatism Axis (°)* 93,70 (11,8; 179) 93,10 (6,70; 176,80) 91,75 (2,80; 177,50) 68,95 (0,10; 177,90) P < 0,001 Anterior Asphericity (Q)* -0,39 (-0,78; -0,07) -0,31 (-0,70; 0,27) -0,30 (-0,77; 0,02) -0,31 (-0,99; 0,03) P < 0,001 Posterior K1-Flat (D)* -6,20 (-6,70; -4,70) -6,10 (-6,80; -5,30) -6,20 (-6,80; -5,50) -6,20 (-6,90; -5,40) 0,122 Posterior K2-Steep (D)* -6,50 (-7,30; -5,90) -6,50 (-7,00; -5,90) -6,40 (-7,60; -5,80) -6,40 (-7,30; -5,80) 0,14 Posterior Kmean (D)* -6,30 (-6,90; -5,20) -6,30 (-6,90; -5,60) -6,30 (-6,90; -5,60) -6,30 (-7,00; -5,60) 0,168 Posterior Rflat (mm)* 6,47 (5,93; 8,42) 6,52 (5,85; 7,51) 6,49 (5,87; 7,30) 6,47 (5,80; 7,44) 0,179 Posterior Rsteep (mm) 6,13 0,26 6,20 0,23 6,21 0,29 6,21 0,27 0,012 Posterior Rmean (mm) 6,32 0,24 6,36 0,22 6,36 0,27 6,34 0,27 0,344 Posterior Astigmatism (D)* 0,30 (0; 1,40) 0,30 0;0,80 0,30 (0; 1,20) 0,20 (0; 0,90) P < 0,001 Posterior Steep Astigmatism Axis (°)* 91,05 (11,40;163,40) 93,10 (55,10;139,20) 97,50 (24,90;173,60) 99,25 (3,20; 167,80) P < 0,001 *: Mann-Whitney Test (Median (Min; Max)) Pentacam Parameters 3–19 (n = 196) 20–39 (n = 163) 40–59 (n = 114) 60 years and above (n = 128) Mean Standard Deviation (SD) Mean Standard Deviation (SD) Mean Standard Deviation (SD) Mean Standard Deviation (SD) p-value Posterior Asphericity (Q) -0,34 0,15 -0,35 0,15 -0,45 0,18 -0,48 0,18 P < 0,001 Thinnest Corneal Point (µm) 558,52 32,91 543,35 33,06 545,64 31,86 539,56 39,97 P < 0,001 Corneal Volume (mm³) 62,83 3,47 61,42 3,44 60,76 3,15 58,93 4,31 P < 0,001 Anterior Chamber Volume (mm³) 189,95 32,90 184,71 36,98 138,39 33,30 134,42 42,11 P < 0,001 Anterior Chamber Depth (mm) 3,17 0,37 3,22 0,40 2,80 0,49 2,87 0,60 0,003 *: Mann-Whitney Test (Median (Min; Max)) Astigmatism Value and Astigmatism Axis (Anterior Astigmatism and Anterior Steep Astigmatism Axis): In the analysis of anterior astigmatism values by age groups, pairwise group comparisons revealed statistically significant difference was observed between the 3–19 years group and both the 40–59 years group (p < 0.01) and the 60 + group (p = 0.001). However, no statistically significant difference was found between the other groups. In the analysis of anterior steep astigmatism axis by age groups, pairwise group comparisons revealed statistically significant difference was observed between the 60 + group and the 3–19 years group, 20–39 years group, and 40–59 years group (p < 0.01). However, no statistically significant difference was found between the other groups. The relationship between age and the regularity of anterior astigmatism is shown in the graph 1 . With increasing age, a decrease in with-the-rule astigmatism and an increase in against-the-rule and oblique astigmatism were observed on the anterior corneal surface. Anterior Corneal Asphericity (Q) was analyzed for pairwise group comparisons. A statistically significant difference was observed between the 3–19 years group and the 20–39 years group, 40–59 years group, and 60 + group (p < 0.01). However, no statistically significant difference was found between the other groups. The posterior K1-Flat (D) K2-Steep (D) and Kmean of the posterior corneal surface was analyzed for pairwise group comparisons. No statistically significant difference was found for posterior K1 Flat (p = 0.122). A statistically significant difference was observed between the 3–19 years group and the 60 + years group for posterior K2-Steep (p = 0.030). However, no statistically significant difference was found between the other groups. No statistically significant difference was found for posterior Kmean (p = 0.168). Astigmatism Value and Astigmatism Axis (Posterior Astigmatism and Posterior Steep Astigmatism Axis): In the analysis of posterior astigmatism values by age groups, pairwise group comparisons: A statistically significant difference was observed between the 3–19 years group and both the 40–59 years group (p = 0.001) and the 60 + group (p < 0.01). A statistically significant difference was also observed between the 20–39 years group and both the 40–59 years group (p = 0.003) and the 60 + group (p < 0.01). No statistically significant difference was found between the other age groups. In the analysis of posterior steep astigmatism axis by age groups, pairwise group comparisons: A statistically significant difference was observed between the 3–19 years group and both the 40–59 years group and the 60 years and above group (p < 0.01). A statistically significant difference was also observed between the 20–39 years group and the 60 years and above group (p = 0.015). No statistically significant difference was found between the other age groups. The relationship between age and the regularity of posterior astigmatism is shown in the graph 2. With increasing age, an increase in with-the-rule and oblique astigmatism and a decrease in against-the-rule astigmatism were observed on the posterior corneal surface. Posterior Corneal Asphericity (Q) was analyzed for pairwise group comparisons. A statistically significant difference was observed between the 3–19 years group and both the 40–59 years group and the 60 years and above group (p < 0.01). A statistically significant difference was also observed between the 20–39 years group and both the 40–59 years group and the 60 years and above group (p < 0.01). Thinnest value of the cornea was analyzed for pairwise group comparisons. A statistically significant differences were observed between the 3–19 age group and the 20–39 age group, the 40–59 age group, and the 60 +(p < 0.01, p = 0.09, p < 0.01). No statistically significant differences were found between other groups. Corneal volume was analyzed for pairwise group comparisons. A statistically significant differences were observed between the 3–19 age group and the 20–39 age group, the 40–59 age group, and the 60 + group(p = 0.02, p < 0.01, p < 0.01). Statistically significant differences were also observed between the 60 + and the 20–39 age group and the 40–59 age group (p < 0.01, p = 0.01). No statistically significant differences were found between other groups. Anterior chamber volume was analyzed for pairwise group comparisons. A statistically significant differences were observed between the 3–19 age group and the 40–59 age group and the 60 +(p < 0.01). Statistically significant differences were also observed between the 20–39 age group and the 40–59 age group and the 60 + (p < 0.01). Anterior chamber depth was analyzed for pairwise group comparisons. A statistically significant differences were observed between the 3–19 age group and the 40–59 age group and the 60 +(p < 0.01). Statistically significant differences were also observed between the 20–39 age group and the 40–59 age group and the 60 + (p < 0.01). Correlation relationships between the parameters; A strong correlation was observed between the right and left eyes for all corneal parameters. The correlations between the parameters are presented in the Table 3 . A very strong correlation was found between anterior K1 and K2, as well as between anterior K1 and Kmean (r² = 0.749, r² = 0.966). Additionally, a very strong correlation was detected between anterior K2 and Kmean (r² = 0.964). A moderate to strong correlation was observed between anterior chamber depth and anterior chamber volume (r² = 0.524). No significant correlations were found among the other parameters. Table 3 Correlation relationships between the parameters Parametreler Anterior Asphericity (Q) Posterior Asphericity (Q) Anterior K1-Flat (D) Anterior K2-Steep (D) Anterior Kmean (D) Anterior Chamber Volume (mm³) Thinnest Corneal Point (µm) Posterior Asphericity (Q) Pearson Correlation .222 ** r² 0,049 p-value 0,000 Anterior K1-Flat (D) Pearson Correlation -0,049 0,069 r² 0,002 0,004 p-value 0,231 0,090 Anterior K2-Steep (D) Pearson Correlation − .170 ** 0,064 .866 ** r² 0,028 0,004 0,749 p-value 0,000 0,119 0,000 Anterior Kmean (D) Pearson Correlation − .112 ** 0,070 .966 ** .964 ** r² 0,012 0,049 0,933 0,929 p-value 0,006 0,087 0,000 0,000 Anterior Chamber Volume (mm³) Pearson Correlation .110 ** .405 ** − .121 ** − .100 * − .114 ** r² 0,012 0,164 0,014 0,01 0,012 p-value 0,007 0,000 0,003 0,014 0,005 Thinnest Corneal Point (µm) Pearson Correlation -0,015 − .111 ** − .152 ** − .120 ** − .138 ** -0,049 r² 0,000 0,012 0,023 0,014 0,019 0,002 p-value 0,720 0,007 0,000 0,003 0,001 0,231 Anterior Chamber Depth (mm) Pearson Correlation .118 ** .324 ** 0,024 0,045 0,036 .724 ** -0,062 r kare 0,013 0,104 0,001 0,002 0,001 0,524 0,003 p 0,004 0,000 0,560 0,271 0,378 0,000 0,128 DISCUSSION Knowing the standard values for healthy corneas is essential for diagnosing various corneal diseases. It is crucial to understand how these values vary with age, gender, and ethnic background. In this study, we examined the anterior and posterior corneal surfaces, as well as anterior segment parameters, and analyzed their variations across different age groups within the Turkish population. The accurate measurement of corneal parameters and the knowledge of their normal values and age-related variations are critical for both the assessment of astigmatism and cataract surgery. This is particularly essential for the calculation and implantation of premium intraocular lens (IOL) power. [ 13 ] There are studies in the literature indicating that keratometric values do not change with age. [ 14 , 15 ] Orucoglu et al. [ 16 ] reported a positive correlation between the anterior corneal surface K1 value and age, while no correlation was found between K2 and age. In our study, K1, K2, and Kmean values of the anterior corneal surface showed a decrease in the 20–39 age group compared to the 3–19 age group, followed by an increase as age advanced. No significant relationship was observed between posterior corneal surface K1 and Kmean values and age. However, the posterior surface K2 value showed a statistically significant increase in the 60 years and above group compared to the 3–19 age group. Nemeth G et al. [ 17 ] found a strong correlation between K1 and K2 values on both the anterior and posterior corneal surfaces. Similarly, in our study, anterior surface keratometric values demonstrated a strong correlation with each other. Dubbelman et al. [ 3 ] reported an average anterior corneal surface radius of 7.79 mm and a posterior surface radius of 6.53 mm using the Scheimpflug system. Ho et al. [ 18 ] found the central curvature radius of the posterior corneal surface to be an average of 6.34 mm using the Pentacam, while Pinero et al. [ 19 ] reported an average of 6.47 mm, also using the Pentacam. Nemeth G et al. [ 17 ] , using measurements obtained with the Pentacam HR, reported that the anterior corneal curvature radius was, on average, 7.77 mm in the horizontal axis and 7.67 mm in the vertical axis, while the posterior corneal curvature radius was 6.49 mm in the horizontal axis and 6.21 mm in the vertical axis. It was demonstrated that corneal radii were significantly larger in males than in females in both the horizontal and vertical axes. In our study, the average anterior and posterior corneal surface radii were found to be 7.79 mm and 6.34 mm, respectively. Similarly, we observed that the corneal curvature radii were significantly greater in males than in females in both the horizontal and vertical axes. Dubbelman et al. [ 20 ] and Hashemi et al. [ 21 ] found no relationship between age and the anterior and posterior corneal surface radii. However, Hayashi et al. [ 22 ] reported a decrease in the anterior corneal surface radius with age, while Lam et al. [ 23 ] and Dubbelman et al. [ 3 ] demonstrated in a separate study that the posterior corneal surface radius also decreases with age. In our study, the Rflat and Rmean parameters of the anterior and posterior corneal surface radii increased in the 20–39 age group compared to the 3–19 age group but subsequently decreased in older age groups. Additionally, the posterior Rsteep parameter showed a continuous increase with age. Ho et al. [ 24 ] stated in 2009 that neglecting posterior corneal astigmatism could lead to significant errors in the calculation of total corneal astigmatism. Koch et al. [ 13 ] conducted a more detailed study on this topic and investigated age-related changes. According to their study, anterior corneal surface astigmatism shifts from with-the-rule (WTR) to against-the-rule (ATR) with aging, while posterior corneal astigmatism remains stable. The largest study on posterior corneal astigmatism was conducted by Tonn et al. [ 25 ] In this study, similar to previous findings, it was observed that anterior corneal surface astigmatism shifts from WTR to ATR with aging, while posterior corneal astigmatism remains stable. These three studies are considered fundamental in understanding posterior corneal astigmatism and guiding toric intraocular lens (IOL) calculations. Failure to account for posterior corneal astigmatism can lead to errors in calculating the power of specialized intraocular lenses. This miscalculation may result in overcorrection in eyes with WTR astigmatism or undercorrection in eyes with ATR astigmatism [ 26 ] . Studies in the literature have observed that with aging, astigmatism shifts from WTR to ATR [ 22 , 23 , 27 – 31 ] . Orucoglu et al. [ 16 ] also reported an increase in ATR astigmatism with age but did not observe a similar trend in posterior corneal astigmatism. Ho et al. [ 27 ] , using measurements obtained with the Pentacam device, observed a shift toward ATR astigmatism on the anterior corneal surface and WTR astigmatism on the posterior corneal surface with aging. The proposed underlying mechanisms for these changes include decreased eyelid tension, reduced tension in extraocular muscles, increased intraocular pressure, and structural changes in the cornea. In our study, it was observed that with increasing age, WTR astigmatism on the anterior corneal surface decreased, while ATR and oblique astigmatism increased. On the posterior corneal surface, WTR and oblique astigmatism increased with age, whereas ATR astigmatism decreased. In a study conducted by Scholz et al. [ 32 ] on 487 eyes, no significant relationship was found between Q value and age; however, a significant difference in Q values between males and females was observed. Orucoglu et al. [ 16 ] reported a positive correlation between anterior corneal asphericity and age, whereas posterior corneal asphericity showed a negative correlation with age. There are studies in the literature that have found no statistically significant difference in corneal asphericity with aging [ 3 , 33 , 34 ] .The anterior corneal surface is typically slightly prolate, and the most widely accepted Q value in the young adult population is approximately − 0.20 [ 3 , 35 ] .In a study conducted by Hashemi et al. [ 6 ] on the elderly Iranian population, the Q value was found to be more negative compared to previous studies. In our study, the anterior corneal asphericity (Q value) was found to be -0.39 in the 3–19 age group, -0.31 in the 20–39 age group, -0.30 in the 40–59 age group, and − 0.31 in the 60 years and above group. It was observed that the cornea in the Turkish population had a more prolate structure compared to African Americans (-0.26 ± 0.19) and Caucasians (-0.20 ± 0.12). [ 36 ] In a study by Zhang et al. [ 37 ] on the Chinese population, a significant difference was observed between the 20–29 and 30–49 age groups, with corneas exhibiting higher prolate values with increasing age. Contrary to this study, our findings showed that the 3–19 age group had a more prolate corneal structure compared to other groups. However, no statistically significant difference was observed among the other age groups. Additionally, Hashemi et al. [ 6 ] found that the posterior corneal asphericity in the elderly Iranian population was less negative (a shift toward positivity) compared to previous studies. In our study, the posterior corneal asphericity (Q value) was found to be -0.34 in the 3–19 age group, -0.35 in the 20–39 age group, -0.45 in the 40–59 age group, and − 0.48 in the 60 years and above group. A marked increase in the negativity of the posterior Q value was observed after the age of 40. Contrary to the findings of Navarro et al. [ 38 ] ,our study observed an increasing difference between anterior and posterior Q values, indicating that the cornea becomes more prolate with aging. The thinnest value of the cornea is a highly important diagnostic parameter for detecting primary ectatic diseases [ 16 , 39 – 42 ] .Studies conducted with Pentacam in the literature have not observed any significant differences in the thinnest value of the cornea concerning age or gender. [ 37 , 43 ] In our study, no difference was observed between males and females. However, in contrast to previous studies, we found that the thinnest value of the cornea decreased with age. A slight increase was observed only in the 40–59 age group, but this change was not statistically significant. ACD and ACV are key risk factors for primary angle-closure glaucoma. They also play a crucial role in selecting the appropriate lens for cataract surgery or phakic intraocular lens implantation. In a normal eye, an ACV of < 100 mm³ and an ACD of < 2.1 mm indicate a high risk for angle-closure glaucoma. [ 44 – 46 ] Studies have demonstrated a negative correlation between ACD and age. [ 47 – 51 ] Additionally, research has shown that, along with ACD, ACV also decreases with age. [ 51 , 52 ] Corneal volume has also been shown to decrease with age. [ 15 , 53 ] The reduction in ACD, and ACV with aging is secondary to lens growth and its forward displacement. [ 54 , 55 ] In our study, ACV, ACD, and corneal volume were observed to decrease with age. Although ACD was higher in the 20–39 age group compared to the 3–19 age group and in the 60 years and above group compared to the 40–59 age group, these differences were not statistically significant. Additionally, no significant difference was found between males and females. In our study, corneal parameters and their age-related changes in the Turkish population were investigated. There are a limited number of comprehensive studies examining corneal parameters and their variations with age in the Turkish population. As a result, it was observed that with aging, the cornea became more prolate. On the anterior corneal surface, WTR astigmatism decreased, while ATR and oblique astigmatism increased. On the posterior corneal surface, WTR and oblique astigmatism increased with age, whereas ATR astigmatism decreased. A negative correlation was observed between age and ACV, ACD, corneal volume, and the thinnest value of the cornea. Declarations Ethics approval and consent to participate: This retrospective study was conducted in accordance with the Declaration of Helsinki. Ethical approval was obtained from the Dokuz Eylul University Faculty of Medicine Non-Interventional Clinical Research Ethics Committee (Approval No: 2021/36-11). The requirement for obtaining individual informed consent was explicitly waived by this committee , because only anonymized, routinely collected clinical data were analysed and no additional procedures were performed, in line with Turkish national regulations governing retrospective clinical research (Regulation on Clinical Research, Official Gazette No. 28617). Consent for publication: Not applicable. Availability of data and materials: The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable reques. Competing interests: The authors declare that they have no competing interests. Funding: No funds, grants, or other support were received. Authors' contributions: I.D. designed the study and supervised the project. D.O. collected and analyzed the data, prepared the figures and conducted the statistical analysis, wrote the main manuscript text. All authors reviewed and approved the final version of the manuscript. 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Central and peripheral pachymetry measurements according to age using the Pentacam rotating Scheimpflug camera. J Cataract Refract Surg. 2007;33(5):830–6. Sinjab MM. Step by Step: Reading Pentacam Topography: (Basic and Case Study Series). Second Edition . Sinjab MM. Corneal Topography in Clinical Practice (Pentacam System) Basics and Clinical Interpretation. Second Edition . User Guide Pentacam® /Pentacam® HR (UG/70700/0213/en) . Fernández-Vigo JI, et al. Determinants of anterior chamber depth in a large Caucasian population and agreement between intra-ocular lens Master and Pentacam measurements of this variable. Acta Ophthalmol. 2016;94(2):e150–5. Rüfer F, et al. Anterior chamber depth and iridocorneal angle in healthy White subjects: effects of age, gender and refraction. Acta Ophthalmol. 2010;88(8):885–90. O'Donnell C, Hartwig A, Radhakrishnan H. Correlations between refractive error and biometric parameters in human eyes using the LenStar 900. Cont Lens Anterior Eye. 2011;34(1):26–31. Sun JH, et al. Factors associated with anterior chamber narrowing with age: an optical coherence tomography study. Invest Ophthalmol Vis Sci. 2012;53(6):2607–10. Qin B, et al. Effects of age on ocular anterior segment dimensions measured by optical coherence tomography. Chin Med J (Engl). 2011;124(12):1829–34. Lam AK, Tse JS. Pentacam anterior chamber parameters in young and middle-aged Chinese. Clin Exp Optom. 2013;96(1):85–91. Hashemi H, et al. Distribution of Corneal Volume and Its Associated Factors in an Elderly Population: Tehran Geriatric Eye Study. Cornea. 2023;42(9):1092–8. Fontana ST, Brubaker RF. Volume and depth of the anterior chamber in the normal aging human eye. Arch Ophthalmol. 1980;98(10):1803–8. Cook CA, et al. Aging of the human crystalline lens and anterior segment. Vis Res. 1994;34(22):2945–54. Additional Declarations No competing interests reported. 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1","display":"","copyAsset":false,"role":"figure","size":774087,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eGraph 1: \u003c/strong\u003eThe relationship between age and the regularity of anterior astigmatism.\u003c/p\u003e","description":"","filename":"Graph1Uniform1200dpi.png","url":"https://assets-eu.researchsquare.com/files/rs-7851657/v1/03e239dc97645361a6475192.png"},{"id":97894940,"identity":"d5754f00-68f2-49a1-881e-2252171ec1e1","added_by":"auto","created_at":"2025-12-10 15:33:15","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":687977,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eGraph 2:\u003c/strong\u003e The relationship between age and the regularity of posterior astigmatism.\u003c/p\u003e","description":"","filename":"Graph2Uniform1200dpi.png","url":"https://assets-eu.researchsquare.com/files/rs-7851657/v1/9ea730b2ebc93bdfad361904.png"},{"id":98621813,"identity":"56fc1c8a-959f-4a2e-b9d8-40a68efa8068","added_by":"auto","created_at":"2025-12-19 16:20:14","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3364541,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7851657/v1/f067517d-01c2-4805-a310-10e8fed4e8c4.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eAge-related Changes in Corneal Parameters in the Turkish Population: A Pentacam-based Study\u003c/p\u003e","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eCorneal refractive power is determined by the parameters of the anterior and posterior corneal surfaces, along with corneal thickness. As with many other organs, aging leads to changes in corneal parameters. Understanding age-related changes in the cornea across different populations is essential for distinguishing between pathological and physiological alterations. Corneal parameters are crucial in evaluating ectatic corneal disorders, which are characterized by progressive structural deformation, and in determining the optimal treatment. Additionally, corneal thickness serve as an important parameter in the diagnosis of glaucoma.\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e A review of the literature reveals age-related changes in corneal thickness, corneal asphericity, as well as anterior and posterior astigmatism values and their axes across different populations.\u003csup\u003e[\u003cspan additionalcitationids=\"CR3 CR4 CR5\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e Determining age-related changes in these parameters and understanding the overall shape of the cornea enhance the success of various ocular surgeries, particularly refractive surgery. Recognizing the influence of posterior corneal astigmatism on total corneal astigmatism has highlighted the importance of corneal parameters in calculating and implanting intraocular lens power during cataract surgery.\u003csup\u003e[\u003cspan additionalcitationids=\"CR8 CR9 CR10\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eIn cases where posterior corneal astigmatism cannot be directly measured, estimating PCA based on parameters such as age, sex, or other biometric factors may significantly reduce toric intraocular lens calculation errors. The aim of our study is to determine the anterior and posterior corneal surface parameters, as well as anterior segment parameters, in the Turkish population using the Pentacam (Oculus Optikger\u0026auml;te GmbH, Wetzlar, Germany) topography device and to analyze the age-related variations in these parameters.\u003c/p\u003e"},{"header":"MATERIALS AND METHODS","content":"\u003cp\u003eA detailed refractive examination and biomicroscopic evaluation were performed on all patients who presented to the Ophthalmology Clinic of Dokuz Eyl\u0026uuml;l University Faculty of Medicine. Uncorrected visual acuity and best-corrected visual acuity (BCVA) values were recorded. A routine fundus examination was conducted. Data from individuals who underwent corneal topography measurements using the high-resolution Scheimpflug imaging system, the Pentacam corneal topography device, and who had no detected pathology were analyzed. This study was approved by the Ethical Committee of Dokuz Eyl\u0026uuml;l University Faculty of Medicine (2021/36\u0026thinsp;\u0026minus;\u0026thinsp;11) and was conducted in accordance with the ethical principles stated in the Declaration of Helsinki and local regulations.\u003c/p\u003e\u003cp\u003eThe inclusion criteria were defined as follows: completion of a comprehensive ophthalmologic examination, acquisition of corneal topography, being over the age of 3 years, and having no history of surgery or disease that could alter the anatomical structure of the cornea. The exclusion criteria included the presence of any ocular pathology other than refractive errors, a history of ocular disease, or a history of ocular surgery. Patients who met these criteria and presented to the clinic between October 1, 2021, and December 31, 2022, were included in the study.\u003c/p\u003e\u003cp\u003eEach morning, the topography device was calibrated. Corneal topography measurements were conducted between 08:30 AM and 5:00 PM by two different technicians. The same protocol was followed for all patients during the scanning process. Patients were positioned with their chins resting on the chin rest and their foreheads on the forehead strap, ensuring that their heads were completely horizontal. The room lights were turned off during image acquisition. Before the scan, patients were instructed to blink several times to prevent aberrations caused by tear film irregularities and to focus on the target at the center of the blue fixation light. Measurements were automatically performed using the Pentacam corneal topography device once the image was properly focused and the corneal apex was correctly aligned. After all measurements, error margins were checked, and only the highest-quality image data were included in the study.\u003c/p\u003e\u003cp\u003ePatients were categorized into four age groups: 3\u0026ndash;19 years, 20\u0026ndash;39 years, 40\u0026ndash;59 years, and 60 years and above (60+). Corneal parameter values were analyzed according to these age groups, and age-related changes in these parameters were investigated. The keratometric values of the anterior and posterior corneal surfaces (K1, K2, and Kmean), astigmatism and its axes, the axes of the anterior and posterior corneal surfaces, radii of curvature (Rflat, Rsteep, Rmean), asphericity values (Q value), the thinnest value of the cornea, corneal volume, anterior chamber volume (ACV), anterior chamber depth (ACD), and ophthalmologic examination findings were retrospectively analyzed.\u003c/p\u003e\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eSTATISTICAL ANALYSIS\u003c/h2\u003e\u003cp\u003eThe t-test was used to determine differences between gender groups. The normality of the data distribution across age groups was assessed. For variables that followed a normal distribution, variance analysis (ANOVA) was applied. Corneal parameters were analyzed according to age groups. In cases where a significant difference was found in these analyses, Bonferroni post hoc test was conducted for pairwise comparisons between groups.\u003c/p\u003e\u003cp\u003eFor variables that did not follow a normal distribution, the Kruskal-Wallis variance analysis was performed. In cases where a significant difference was detected, Dunn\u0026rsquo;s test was applied for pairwise comparisons. For normally distributed variables, results were presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD). For non-normally distributed variables, results were expressed as median (min, max). Categorical variables were summarized as frequencies and percentages. The relationships between numerical variables were assessed using Pearson\u0026rsquo;s correlation coefficient. The level of statistical significance was set at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.All statistical analyses were performed using IBM-SPSS version 25.0.\u003c/p\u003e\u003cp\u003ePearson correlation analysis was performed to determine the relationship between the same parameters in the right and left eyes. All statistical analyses were conducted based on the right eye data. A significance level of p\u0026thinsp;\u0026lt;\u0026thinsp;0.01 was considered for correlation analyses. Correlation strength was classified as follows: 0\u0026ndash;0.25: No correlation, 0.25\u0026ndash;0.50: Weak correlation, 0.50\u0026ndash;0.75: Moderate to good correlation, \u0026gt;0.75: Very strong correlation.\u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eThe results of these correlation analyses were interpreted based on the defined correlation strength categories, with statistical significance set at \u003cb\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.01\u003c/b\u003e.\u003c/p\u003e\u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003eA total of 601 patients (1202 eyes) were included in the study. The age of the cases ranged from 3 to 86 years, with a mean age of 35.25\u0026thinsp;\u0026plusmn;\u0026thinsp;23.02 years. 295 patients (49.1%) were male, and 306 patients (50.9%) were female. The mean age of male patients was 35.99\u0026thinsp;\u0026plusmn;\u0026thinsp;23.79 years (Range:4\u0026ndash;85), while the mean age of female patients was 34.53\u0026thinsp;\u0026plusmn;\u0026thinsp;22.27 years (Range:3\u0026ndash;86). The difference in mean age between genders was not statistically significant (p\u0026thinsp;=\u0026thinsp;0.436).\u003c/p\u003e\u003cp\u003eThe distribution of patients across age groups was as follows: 196 patients (32.61%) in the 3\u0026ndash;19 years age group, 163 patients (27.12%) in the 20\u0026ndash;39 years age group, 114 patients (18.97%) in the 40\u0026ndash;59 years age group, 128 patients (21.30%) in the 60\u0026thinsp;+\u0026thinsp;group. When examining the distribution of patients across age groups, no statistically significant difference was observed (p\u0026thinsp;=\u0026thinsp;0.436).\u003c/p\u003e\u003cp\u003eThe average corneal parameters in males and females are shown in the Table \u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Statistically, anterior K1, anterior K2, anterior Kmean, posterior K1, posterior K2, posterior Kmean, posterior Rflat, and posterior Rmean were found to be higher in females compared to males, whereas anterior Rflat, anterior Rsteep, and anterior Rmean were lower in females. (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) No significant difference was observed in anterior and posterior astigmatism, posterior steep astigmatism axis, anterior and posterior asphericity, thinnest corneal point, corneal volume, and anterior chamber depth between males and females.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eAverage Pentacam Parameter Values by Gender\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMale (n\u0026thinsp;=\u0026thinsp;295)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eFemale\u003c/p\u003e\u003cp\u003e(n\u0026thinsp;=\u0026thinsp;306)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePentacam Parameters\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMean\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eStandard Deviation (SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMean\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eStandard Deviation (SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior K1-Flat (D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e42,47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1,50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e43,05\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1,42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior K2-Steep (D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e43,64\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1,54\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e44,10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1,53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Kmean(D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e43,05\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1,46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e43,57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1,43\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Rflat (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7,96\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7,85\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Rsteep (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7,74\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7,66\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Rmean (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7,84\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7,75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Astigmatism (D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1,18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,88\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1,06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,69\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,066\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Steep Astigmatism Axis (\u0026deg;)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e91,31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e36,81\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e85,03\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e31,73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,025\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Asphericity (Q)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-0,33\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-0,35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,073\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior K1-Flat (D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-6,11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-6,20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior K2-Steep (D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-6,46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-6,52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Kmean(D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-6,28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-6,35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Rflat (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6,55\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6,46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Rsteep (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6,21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6,15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,002\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Rmean (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6,38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6,31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Astigmatism (D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0,34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,154\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Steep Astigmatism Axis (\u0026deg;)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e96,10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e23,86\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e93,53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e19,22\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,145\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Asphericity (Q)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-0,39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-0,39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,601\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eThinnest Corneal Point (\u0026micro;m)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e549,94\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e36,93\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e545,98\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e33,26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,168\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCorneal Volume (mm\u0026sup3;)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e61,23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e3,98\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e61,21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e3,76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,943\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Chamber Volume (mm\u0026sup3;)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e170,85\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e44,42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e163,13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e43,53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,032\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Chamber Depth (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3,06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0,46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e3,04\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0,52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,572\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eThe analysis of Pentacam parameters by age groups is shown in the Table \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. The anterior K1-Flat (D) K2-Steep (D) and Kmean of the anterior corneal surface was analyzed for pairwise group comparisons. A statistically significant difference was observed between the 60\u0026thinsp;+\u0026thinsp;group and both the 20\u0026ndash;39 years group (p\u0026thinsp;=\u0026thinsp;0.002) and the 40\u0026ndash;59 years group (p\u0026thinsp;=\u0026thinsp;0.022). However, no statistically significant difference was found between the other age groups. A statistically significant difference was observed between the 20\u0026ndash;39 years group and both the 3\u0026ndash;19 years group (p\u0026thinsp;=\u0026thinsp;0.012) and the 60 years and above group (p\u0026thinsp;=\u0026thinsp;0.020)for anterior K2-Steep (D). However, no statistically significant difference was found between the other age groups. For the anterior Kmean, a statistically significant difference was observed between the 60\u0026thinsp;+\u0026thinsp;group and both the 20\u0026ndash;39 years group (p\u0026thinsp;=\u0026thinsp;0.006) and the 40\u0026ndash;59 years group (p\u0026thinsp;=\u0026thinsp;0.031). However, no statistically significant difference was found between the other age groups.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eAnalysis of Pentacam Parameters by Age Groups\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"10\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003ePentacam Parameters\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003e3\u0026ndash;19 (n\u0026thinsp;=\u0026thinsp;196)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e\u003cp\u003e20\u0026ndash;39 (n\u0026thinsp;=\u0026thinsp;163)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e\u003cp\u003e40\u0026ndash;59 (n\u0026thinsp;=\u0026thinsp;114)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e\u003cp\u003e60 years and above (n\u0026thinsp;=\u0026thinsp;128)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMean\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eStandard Deviation (SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMean\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eStandard Deviation (SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eMean\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eStandard Deviation (SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eMean\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003eStandard Deviation (SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c10\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior K1-Flat (D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e42,83\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1,37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e42,52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1,46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e42,59\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1,50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e43,14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e1,62\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,002\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior K2-Steep (D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e44,09\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1,45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e43,59\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1,53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e43,63\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1,60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e44,12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e1,60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Kmean(D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e43,45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1,36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e43,06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1,45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e43,10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1,47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e43,63\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e1,57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,002\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Rflat (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7,89\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7,95\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e7,93\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e7,83\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0,30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,003\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Rsteep (mm))\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7,66\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7,75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e7,75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e7,66\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0,28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Rmean (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7,77\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7,85\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e7,84\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e7,75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0,28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,002\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Astigmatism (D)*\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1,10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(0.10; 4.20)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,90\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(0; 3.40)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,70\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e(0.10; 5.30)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0,80\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e(0; 4.70)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0,001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Steep Astigmatism Axis (\u0026deg;)*\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e93,70\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(11,8; 179)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e93,10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(6,70; 176,80)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e91,75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e(2,80; 177,50)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e68,95\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e(0,10; 177,90)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0,001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Asphericity (Q)*\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-0,39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(-0,78; -0,07)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-0,31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(-0,70; 0,27)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-0,30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e(-0,77; 0,02)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e-0,31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e(-0,99; 0,03)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0,001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior K1-Flat (D)*\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-6,20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(-6,70; -4,70)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-6,10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(-6,80; -5,30)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-6,20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e(-6,80; -5,50)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e-6,20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e(-6,90; -5,40)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,122\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior K2-Steep (D)*\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-6,50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(-7,30; -5,90)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-6,50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(-7,00; -5,90)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-6,40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e(-7,60; -5,80)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e-6,40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e(-7,30; -5,80)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,14\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Kmean (D)*\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-6,30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(-6,90; -5,20)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-6,30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(-6,90; -5,60)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-6,30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e(-6,90; -5,60)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e-6,30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e(-7,00; -5,60)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,168\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Rflat (mm)*\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6,47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(5,93; 8,42)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6,52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(5,85; 7,51)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e6,49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e(5,87; 7,30)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e6,47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e(5,80; 7,44)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,179\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Rsteep (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6,13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6,20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e6,21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e6,21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0,27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,012\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Rmean (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6,32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6,36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,22\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e6,36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e6,34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0,27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,344\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Astigmatism (D)*\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0,30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(0; 1,40)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0;0,80\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e(0; 1,20)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0,20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e(0; 0,90)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0,001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Steep Astigmatism Axis (\u0026deg;)*\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e91,05\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(11,40;163,40)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e93,10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(55,10;139,20)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e97,50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e(24,90;173,60)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e99,25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e(3,20; 167,80)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0,001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"10\" nameend=\"c10\" namest=\"c1\"\u003e\u003cp\u003e\u003cb\u003e*: Mann-Whitney Test (Median (Min; Max))\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003ePentacam Parameters\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003e\u003cb\u003e3\u0026ndash;19 (n\u0026thinsp;=\u0026thinsp;196)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e\u003cp\u003e\u003cb\u003e20\u0026ndash;39 (n\u0026thinsp;=\u0026thinsp;163)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e\u003cp\u003e\u003cb\u003e40\u0026ndash;59 (n\u0026thinsp;=\u0026thinsp;114)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e\u003cp\u003e\u003cb\u003e60 years and above (n\u0026thinsp;=\u0026thinsp;128)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eMean\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003eStandard Deviation (SD)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003eMean\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003eStandard Deviation (SD)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003eMean\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cb\u003eStandard Deviation (SD)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u003cb\u003eMean\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e\u003cb\u003eStandard Deviation (SD)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e\u003cb\u003ep-value\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Asphericity (Q)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-0,34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-0,35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-0,45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e-0,48\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0,18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0,001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eThinnest Corneal Point (\u0026micro;m)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e558,52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e32,91\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e543,35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e33,06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e545,64\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e31,86\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e539,56\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e39,97\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0,001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCorneal Volume (mm\u0026sup3;)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e62,83\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3,47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e61,42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3,44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e60,76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e3,15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e58,93\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e4,31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0,001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Chamber Volume (mm\u0026sup3;)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e189,95\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e32,90\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e184,71\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e36,98\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e138,39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e33,30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e134,42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e42,11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0,001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Chamber Depth (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3,17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e3,22\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2,80\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e2,87\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0,60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0,003\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"10\" nameend=\"c10\" namest=\"c1\"\u003e\u003cp\u003e\u003cb\u003e*: Mann-Whitney Test (Median (Min; Max))\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\n\u003ch3\u003eAstigmatism Value and Astigmatism Axis (Anterior Astigmatism and Anterior Steep Astigmatism Axis):\u003c/h3\u003e\n\u003cp\u003eIn the analysis of anterior astigmatism values by age groups, pairwise group comparisons revealed statistically significant difference was observed between the 3\u0026ndash;19 years group and both the 40\u0026ndash;59 years group (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01) and the 60\u0026thinsp;+\u0026thinsp;group (p\u0026thinsp;=\u0026thinsp;0.001). However, no statistically significant difference was found between the other groups.\u003c/p\u003e\u003cp\u003eIn the analysis of anterior steep astigmatism axis by age groups, pairwise group comparisons revealed statistically significant difference was observed between the 60\u0026thinsp;+\u0026thinsp;group and the 3\u0026ndash;19 years group, 20\u0026ndash;39 years group, and 40\u0026ndash;59 years group (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01). However, no statistically significant difference was found between the other groups.\u003c/p\u003e\u003cp\u003eThe relationship between age and the regularity of anterior astigmatism is shown in the \u003cb\u003egraph 1\u003c/b\u003e. With increasing age, a decrease in with-the-rule astigmatism and an increase in against-the-rule and oblique astigmatism were observed on the anterior corneal surface.\u003c/p\u003e\u003cp\u003eAnterior Corneal Asphericity (Q) was analyzed for pairwise group comparisons. A statistically significant difference was observed between the 3\u0026ndash;19 years group and the 20\u0026ndash;39 years group, 40\u0026ndash;59 years group, and 60\u0026thinsp;+\u0026thinsp;group (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01). However, no statistically significant difference was found between the other groups.\u003c/p\u003e\u003cp\u003eThe posterior K1-Flat (D) K2-Steep (D) and Kmean of the posterior corneal surface was analyzed for pairwise group comparisons. No statistically significant difference was found for posterior K1 Flat (p\u0026thinsp;=\u0026thinsp;0.122). A statistically significant difference was observed between the 3\u0026ndash;19 years group and the 60\u0026thinsp;+\u0026thinsp;years group for posterior K2-Steep (p\u0026thinsp;=\u0026thinsp;0.030). However, no statistically significant difference was found between the other groups. No statistically significant difference was found for posterior Kmean (p\u0026thinsp;=\u0026thinsp;0.168).\u003c/p\u003e\n\u003ch3\u003eAstigmatism Value and Astigmatism Axis (Posterior Astigmatism and Posterior Steep Astigmatism Axis):\u003c/h3\u003e\n\u003cp\u003eIn the analysis of posterior astigmatism values by age groups, pairwise group comparisons: A statistically significant difference was observed between the 3\u0026ndash;19 years group and both the 40\u0026ndash;59 years group (p\u0026thinsp;=\u0026thinsp;0.001) and the 60\u0026thinsp;+\u0026thinsp;group (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01). A statistically significant difference was also observed between the 20\u0026ndash;39 years group and both the 40\u0026ndash;59 years group (p\u0026thinsp;=\u0026thinsp;0.003) and the 60\u0026thinsp;+\u0026thinsp;group (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01). No statistically significant difference was found between the other age groups.\u003c/p\u003e\u003cp\u003eIn the analysis of posterior steep astigmatism axis by age groups, pairwise group comparisons: A statistically significant difference was observed between the 3\u0026ndash;19 years group and both the 40\u0026ndash;59 years group and the 60 years and above group (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01). A statistically significant difference was also observed between the 20\u0026ndash;39 years group and the 60 years and above group (p\u0026thinsp;=\u0026thinsp;0.015). No statistically significant difference was found between the other age groups.\u003c/p\u003e\u003cp\u003eThe relationship between age and the regularity of posterior astigmatism is shown in the \u003cb\u003egraph 2.\u003c/b\u003e With increasing age, an increase in with-the-rule and oblique astigmatism and a decrease in against-the-rule astigmatism were observed on the posterior corneal surface.\u003c/p\u003e\u003cp\u003ePosterior Corneal Asphericity (Q) was analyzed for pairwise group comparisons. A statistically significant difference was observed between the 3\u0026ndash;19 years group and both the 40\u0026ndash;59 years group and the 60 years and above group (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01). A statistically significant difference was also observed between the 20\u0026ndash;39 years group and both the 40\u0026ndash;59 years group and the 60 years and above group (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01).\u003c/p\u003e\u003cp\u003eThinnest value of the cornea was analyzed for pairwise group comparisons. A statistically significant differences were observed between the 3\u0026ndash;19 age group and the 20\u0026ndash;39 age group, the 40\u0026ndash;59 age group, and the 60 +(p\u0026thinsp;\u0026lt;\u0026thinsp;0.01, p\u0026thinsp;=\u0026thinsp;0.09, p\u0026thinsp;\u0026lt;\u0026thinsp;0.01). No statistically significant differences were found between other groups.\u003c/p\u003e\u003cp\u003eCorneal volume was analyzed for pairwise group comparisons. A statistically significant differences were observed between the 3\u0026ndash;19 age group and the 20\u0026ndash;39 age group, the 40\u0026ndash;59 age group, and the 60\u0026thinsp;+\u0026thinsp;group(p\u0026thinsp;=\u0026thinsp;0.02, p\u0026thinsp;\u0026lt;\u0026thinsp;0.01, p\u0026thinsp;\u0026lt;\u0026thinsp;0.01). Statistically significant differences were also observed between the 60\u0026thinsp;+\u0026thinsp;and the 20\u0026ndash;39 age group and the 40\u0026ndash;59 age group (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01, p\u0026thinsp;=\u0026thinsp;0.01). No statistically significant differences were found between other groups.\u003c/p\u003e\u003cp\u003eAnterior chamber volume was analyzed for pairwise group comparisons. A statistically significant differences were observed between the 3\u0026ndash;19 age group and the 40\u0026ndash;59 age group and the 60 +(p\u0026thinsp;\u0026lt;\u0026thinsp;0.01). Statistically significant differences were also observed between the 20\u0026ndash;39 age group and the 40\u0026ndash;59 age group and the 60 + (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01).\u003c/p\u003e\u003cp\u003eAnterior chamber depth was analyzed for pairwise group comparisons. A statistically significant differences were observed between the 3\u0026ndash;19 age group and the 40\u0026ndash;59 age group and the 60 +(p\u0026thinsp;\u0026lt;\u0026thinsp;0.01). Statistically significant differences were also observed between the 20\u0026ndash;39 age group and the 40\u0026ndash;59 age group and the 60 + (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01).\u003c/p\u003e\u003cp\u003e\u003cb\u003eCorrelation relationships between the parameters;\u003c/b\u003e\u003c/p\u003e\u003cp\u003eA strong correlation was observed between the right and left eyes for all corneal parameters. The correlations between the parameters are presented in the Table \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. A very strong correlation was found between anterior K1 and K2, as well as between anterior K1 and Kmean (r\u0026sup2; = 0.749, r\u0026sup2; = 0.966). Additionally, a very strong correlation was detected between anterior K2 and Kmean (r\u0026sup2; = 0.964). A moderate to strong correlation was observed between anterior chamber depth and anterior chamber volume (r\u0026sup2; = 0.524). No significant correlations were found among the other parameters.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eCorrelation relationships between the parameters\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"9\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eParametreler\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAnterior Asphericity (Q)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePosterior Asphericity (Q)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eAnterior K1-Flat (D)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eAnterior K2-Steep (D)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eAnterior Kmean (D)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eAnterior Chamber Volume (mm\u0026sup3;)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003eThinnest Corneal Point (\u0026micro;m)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePosterior Asphericity (Q)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePearson Correlation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e.222\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003er\u0026sup2;\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,049\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior K1-Flat (D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePearson Correlation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-0,049\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,069\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003er\u0026sup2;\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,002\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,004\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,231\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,090\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior K2-Steep (D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePearson Correlation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026minus;\u0026thinsp;.170\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,064\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e.866\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003er\u0026sup2;\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,028\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,004\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,749\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,119\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Kmean (D)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePearson Correlation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026minus;\u0026thinsp;.112\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,070\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e.966\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.964\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003er\u0026sup2;\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,012\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,049\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,933\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,929\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,006\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,087\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Chamber Volume (mm\u0026sup3;)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePearson Correlation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e.110\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e.405\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026minus;\u0026thinsp;.121\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u0026minus;\u0026thinsp;.100\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u0026minus;\u0026thinsp;.114\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003er\u0026sup2;\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,012\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,164\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,014\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,01\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,012\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,007\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,003\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,014\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,005\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eThinnest Corneal Point (\u0026micro;m)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePearson Correlation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-0,015\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026minus;\u0026thinsp;.111\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026minus;\u0026thinsp;.152\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u0026minus;\u0026thinsp;.120\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u0026minus;\u0026thinsp;.138\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e-0,049\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003er\u0026sup2;\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,012\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,023\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,014\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,019\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0,002\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,720\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,007\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,003\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0,231\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAnterior Chamber Depth (mm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePearson Correlation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e.118\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e.324\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,024\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,045\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,036\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e.724\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e-0,062\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003er kare\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,013\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,104\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,002\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0,524\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0,003\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ep\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0,004\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0,000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0,560\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0,271\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0,378\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0,000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0,128\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eKnowing the standard values for healthy corneas is essential for diagnosing various corneal diseases. It is crucial to understand how these values vary with age, gender, and ethnic background. In this study, we examined the anterior and posterior corneal surfaces, as well as anterior segment parameters, and analyzed their variations across different age groups within the Turkish population.\u003c/p\u003e\u003cp\u003eThe accurate measurement of corneal parameters and the knowledge of their normal values and age-related variations are critical for both the assessment of astigmatism and cataract surgery. This is particularly essential for the calculation and implantation of premium intraocular lens (IOL) power.\u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e There are studies in the literature indicating that keratometric values do not change with age.\u003csup\u003e[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/sup\u003e Orucoglu et al.\u003csup\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e reported a positive correlation between the anterior corneal surface K1 value and age, while no correlation was found between K2 and age. In our study, K1, K2, and Kmean values of the anterior corneal surface showed a decrease in the 20\u0026ndash;39 age group compared to the 3\u0026ndash;19 age group, followed by an increase as age advanced. No significant relationship was observed between posterior corneal surface K1 and Kmean values and age. However, the posterior surface K2 value showed a statistically significant increase in the 60 years and above group compared to the 3\u0026ndash;19 age group. Nemeth G et al.\u003csup\u003e[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u003c/sup\u003e found a strong correlation between K1 and K2 values on both the anterior and posterior corneal surfaces. Similarly, in our study, anterior surface keratometric values demonstrated a strong correlation with each other.\u003c/p\u003e\u003cp\u003eDubbelman et al.\u003csup\u003e[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e reported an average anterior corneal surface radius of 7.79 mm and a posterior surface radius of 6.53 mm using the Scheimpflug system. Ho et al.\u003csup\u003e[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/sup\u003e found the central curvature radius of the posterior corneal surface to be an average of 6.34 mm using the Pentacam, while Pinero et al.\u003csup\u003e[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]\u003c/sup\u003e reported an average of 6.47 mm, also using the Pentacam. Nemeth G et al.\u003csup\u003e[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u003c/sup\u003e, using measurements obtained with the Pentacam HR, reported that the anterior corneal curvature radius was, on average, 7.77 mm in the horizontal axis and 7.67 mm in the vertical axis, while the posterior corneal curvature radius was 6.49 mm in the horizontal axis and 6.21 mm in the vertical axis. It was demonstrated that corneal radii were significantly larger in males than in females in both the horizontal and vertical axes. In our study, the average anterior and posterior corneal surface radii were found to be 7.79 mm and 6.34 mm, respectively. Similarly, we observed that the corneal curvature radii were significantly greater in males than in females in both the horizontal and vertical axes.\u003c/p\u003e\u003cp\u003eDubbelman et al.\u003csup\u003e[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/sup\u003e and Hashemi et al.\u003csup\u003e[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]\u003c/sup\u003e found no relationship between age and the anterior and posterior corneal surface radii. However, Hayashi et al.\u003csup\u003e[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]\u003c/sup\u003e reported a decrease in the anterior corneal surface radius with age, while Lam et al.\u003csup\u003e[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]\u003c/sup\u003e and Dubbelman et al.\u003csup\u003e[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e demonstrated in a separate study that the posterior corneal surface radius also decreases with age. In our study, the Rflat and Rmean parameters of the anterior and posterior corneal surface radii increased in the 20\u0026ndash;39 age group compared to the 3\u0026ndash;19 age group but subsequently decreased in older age groups. Additionally, the posterior Rsteep parameter showed a continuous increase with age.\u003c/p\u003e\u003cp\u003eHo et al.\u003csup\u003e[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e stated in 2009 that neglecting posterior corneal astigmatism could lead to significant errors in the calculation of total corneal astigmatism. Koch et al.\u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e conducted a more detailed study on this topic and investigated age-related changes. According to their study, anterior corneal surface astigmatism shifts from with-the-rule (WTR) to against-the-rule (ATR) with aging, while posterior corneal astigmatism remains stable. The largest study on posterior corneal astigmatism was conducted by Tonn et al.\u003csup\u003e[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/sup\u003e In this study, similar to previous findings, it was observed that anterior corneal surface astigmatism shifts from WTR to ATR with aging, while posterior corneal astigmatism remains stable. These three studies are considered fundamental in understanding posterior corneal astigmatism and guiding toric intraocular lens (IOL) calculations. Failure to account for posterior corneal astigmatism can lead to errors in calculating the power of specialized intraocular lenses. This miscalculation may result in overcorrection in eyes with WTR astigmatism or undercorrection in eyes with ATR astigmatism\u003csup\u003e[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]\u003c/sup\u003e. Studies in the literature have observed that with aging, astigmatism shifts from WTR to ATR\u003csup\u003e[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan additionalcitationids=\"CR28 CR29 CR30\" citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]\u003c/sup\u003e. Orucoglu et al.\u003csup\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e also reported an increase in ATR astigmatism with age but did not observe a similar trend in posterior corneal astigmatism.\u003c/p\u003e\u003cp\u003eHo et al.\u003csup\u003e[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]\u003c/sup\u003e, using measurements obtained with the Pentacam device, observed a shift toward ATR astigmatism on the anterior corneal surface and WTR astigmatism on the posterior corneal surface with aging. The proposed underlying mechanisms for these changes include decreased eyelid tension, reduced tension in extraocular muscles, increased intraocular pressure, and structural changes in the cornea. In our study, it was observed that with increasing age, WTR astigmatism on the anterior corneal surface decreased, while ATR and oblique astigmatism increased. On the posterior corneal surface, WTR and oblique astigmatism increased with age, whereas ATR astigmatism decreased.\u003c/p\u003e\u003cp\u003eIn a study conducted by Scholz et al.\u003csup\u003e[\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]\u003c/sup\u003e on 487 eyes, no significant relationship was found between Q value and age; however, a significant difference in Q values between males and females was observed. Orucoglu et al.\u003csup\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e reported a positive correlation between anterior corneal asphericity and age, whereas posterior corneal asphericity showed a negative correlation with age. There are studies in the literature that have found no statistically significant difference in corneal asphericity with aging\u003csup\u003e[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e, \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]\u003c/sup\u003e .The anterior corneal surface is typically slightly prolate, and the most widely accepted Q value in the young adult population is approximately \u0026minus;\u0026thinsp;0.20 \u003csup\u003e[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]\u003c/sup\u003e.In a study conducted by Hashemi et al.\u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e on the elderly Iranian population, the Q value was found to be more negative compared to previous studies. In our study, the anterior corneal asphericity (Q value) was found to be -0.39 in the 3\u0026ndash;19 age group, -0.31 in the 20\u0026ndash;39 age group, -0.30 in the 40\u0026ndash;59 age group, and \u0026minus;\u0026thinsp;0.31 in the 60 years and above group. It was observed that the cornea in the Turkish population had a more prolate structure compared to African Americans (-0.26\u0026thinsp;\u0026plusmn;\u0026thinsp;0.19) and Caucasians (-0.20\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12).\u003csup\u003e[\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]\u003c/sup\u003e In a study by Zhang et al.\u003csup\u003e[\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e]\u003c/sup\u003e on the Chinese population, a significant difference was observed between the 20\u0026ndash;29 and 30\u0026ndash;49 age groups, with corneas exhibiting higher prolate values with increasing age. Contrary to this study, our findings showed that the 3\u0026ndash;19 age group had a more prolate corneal structure compared to other groups. However, no statistically significant difference was observed among the other age groups. Additionally, Hashemi et al.\u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e found that the posterior corneal asphericity in the elderly Iranian population was less negative (a shift toward positivity) compared to previous studies. In our study, the posterior corneal asphericity (Q value) was found to be -0.34 in the 3\u0026ndash;19 age group, -0.35 in the 20\u0026ndash;39 age group, -0.45 in the 40\u0026ndash;59 age group, and \u0026minus;\u0026thinsp;0.48 in the 60 years and above group. A marked increase in the negativity of the posterior Q value was observed after the age of 40. Contrary to the findings of Navarro et al.\u003csup\u003e[\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]\u003c/sup\u003e ,our study observed an increasing difference between anterior and posterior Q values, indicating that the cornea becomes more prolate with aging.\u003c/p\u003e\u003cp\u003eThe thinnest value of the cornea is a highly important diagnostic parameter for detecting primary ectatic diseases\u003csup\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan additionalcitationids=\"CR40 CR41\" citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e]\u003c/sup\u003e .Studies conducted with Pentacam in the literature have not observed any significant differences in the thinnest value of the cornea concerning age or gender.\u003csup\u003e[\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e, \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e]\u003c/sup\u003e In our study, no difference was observed between males and females. However, in contrast to previous studies, we found that the thinnest value of the cornea decreased with age. A slight increase was observed only in the 40\u0026ndash;59 age group, but this change was not statistically significant.\u003c/p\u003e\u003cp\u003eACD and ACV are key risk factors for primary angle-closure glaucoma. They also play a crucial role in selecting the appropriate lens for cataract surgery or phakic intraocular lens implantation. In a normal eye, an ACV of \u0026lt;\u0026thinsp;100 mm\u0026sup3; and an ACD of \u0026lt;\u0026thinsp;2.1 mm indicate a high risk for angle-closure glaucoma.\u003csup\u003e[\u003cspan additionalcitationids=\"CR45\" citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e]\u003c/sup\u003e Studies have demonstrated a negative correlation between ACD and age.\u003csup\u003e[\u003cspan additionalcitationids=\"CR48 CR49 CR50\" citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e]\u003c/sup\u003e Additionally, research has shown that, along with ACD, ACV also decreases with age.\u003csup\u003e[\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e, \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e52\u003c/span\u003e]\u003c/sup\u003e Corneal volume has also been shown to decrease with age.\u003csup\u003e[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e53\u003c/span\u003e]\u003c/sup\u003e The reduction in ACD, and ACV with aging is secondary to lens growth and its forward displacement.\u003csup\u003e[\u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e54\u003c/span\u003e, \u003cspan citationid=\"CR55\" class=\"CitationRef\"\u003e55\u003c/span\u003e]\u003c/sup\u003e In our study, ACV, ACD, and corneal volume were observed to decrease with age. Although ACD was higher in the 20\u0026ndash;39 age group compared to the 3\u0026ndash;19 age group and in the 60 years and above group compared to the 40\u0026ndash;59 age group, these differences were not statistically significant. Additionally, no significant difference was found between males and females.\u003c/p\u003e\u003cp\u003eIn our study, corneal parameters and their age-related changes in the Turkish population were investigated. There are a limited number of comprehensive studies examining corneal parameters and their variations with age in the Turkish population. As a result, it was observed that with aging, the cornea became more prolate. On the anterior corneal surface, WTR astigmatism decreased, while ATR and oblique astigmatism increased. On the posterior corneal surface, WTR and oblique astigmatism increased with age, whereas ATR astigmatism decreased. A negative correlation was observed between age and ACV, ACD, corneal volume, and the thinnest value of the cornea.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u003c/strong\u003e This retrospective study was conducted in accordance with the Declaration of Helsinki. Ethical approval was obtained from the \u003cstrong\u003eDokuz Eylul University Faculty of Medicine Non-Interventional Clinical Research Ethics Committee\u003c/strong\u003e (Approval No: 2021/36-11). The requirement for obtaining individual informed consent was \u003cstrong\u003eexplicitly waived by this committee\u003c/strong\u003e, because only anonymized, routinely collected clinical data were analysed and no additional procedures were performed, in line with Turkish national regulations governing retrospective clinical research (Regulation on Clinical Research, Official Gazette No. 28617).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u003c/strong\u003e Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials:\u003c/strong\u003e The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable reques.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u003c/strong\u003e The authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e No funds, grants, or other support were received.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions:\u0026nbsp;\u003c/strong\u003eI.D. designed the study and supervised the project. D.O. collected and analyzed the data, prepared the figures and conducted the statistical analysis, wrote the main manuscript text. All authors reviewed and approved the final version of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;Acknowledgements:\u0026nbsp;\u003c/strong\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eSalom\u0026atilde;o M, Hoffling-Lima AL, Lopes B, Belin MW, Sena N, Dawson DG et al. Recent developments in keratoconus diagnosis. Exp Rev Ophthalmol 2018;\u003cem\u003e13\u003c/em\u003e(\u003cem\u003e6\u003c/em\u003e):329\u0026ndash;41.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eVit\u0026aacute;lyos G, et al. Effects of aging on corneal parameters measured with Pentacam in healthy subjects. Sci Rep. 2019;9(1):3419.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDubbelman M, Sicam VA, Van der Heijde GL. 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Quant Imaging Med Surg. 2023;13(3):1631\u0026ndash;41.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eNavarro R, Rozema JJ, Tassignon MJ. Optical changes of the human cornea as a function of age. Optom Vis Sci. 2013;90(6):587\u0026ndash;98.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLi Y, et al. Keratoconus diagnosis with optical coherence tomography pachymetry mapping. Ophthalmology. 2008;115(12):2159\u0026ndash;66.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eU\u0026ccedil;akhan \u0026Ouml;, et al. Evaluation of Scheimpflug imaging parameters in subclinical keratoconus, keratoconus, and normal eyes. J Cataract Refract Surg. 2011;37(6):1116\u0026ndash;24.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBae GH, et al. Corneal topographic and tomographic analysis of fellow eyes in unilateral keratoconus patients using Pentacam. Am J Ophthalmol. 2014;157(1):103\u0026ndash;e1091.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAhmadi Hosseini SM, et al. Efficacy of corneal tomography parameters and biomechanical characteristic in keratoconus detection. Cont Lens Anterior Eye. 2014;37(1):26\u0026ndash;30.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKhoramnia R, Rabsilber TM, Auffarth GU. Central and peripheral pachymetry measurements according to age using the Pentacam rotating Scheimpflug camera. J Cataract Refract Surg. 2007;33(5):830\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSinjab MM. \u003cem\u003eStep by Step: Reading Pentacam Topography: (Basic and Case Study Series). Second Edition\u003c/em\u003e.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSinjab MM. \u003cem\u003eCorneal Topography in Clinical Practice (Pentacam System) Basics and Clinical Interpretation. Second Edition\u003c/em\u003e.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e\u003cem\u003eUser Guide Pentacam\u0026reg; /Pentacam\u0026reg; HR (UG/70700/0213/en)\u003c/em\u003e.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFern\u0026aacute;ndez-Vigo JI, et al. Determinants of anterior chamber depth in a large Caucasian population and agreement between intra-ocular lens Master and Pentacam measurements of this variable. Acta Ophthalmol. 2016;94(2):e150\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eR\u0026uuml;fer F, et al. Anterior chamber depth and iridocorneal angle in healthy White subjects: effects of age, gender and refraction. Acta Ophthalmol. 2010;88(8):885\u0026ndash;90.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eO'Donnell C, Hartwig A, Radhakrishnan H. Correlations between refractive error and biometric parameters in human eyes using the LenStar 900. Cont Lens Anterior Eye. 2011;34(1):26\u0026ndash;31.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSun JH, et al. Factors associated with anterior chamber narrowing with age: an optical coherence tomography study. Invest Ophthalmol Vis Sci. 2012;53(6):2607\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eQin B, et al. Effects of age on ocular anterior segment dimensions measured by optical coherence tomography. Chin Med J (Engl). 2011;124(12):1829\u0026ndash;34.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLam AK, Tse JS. Pentacam anterior chamber parameters in young and middle-aged Chinese. Clin Exp Optom. 2013;96(1):85\u0026ndash;91.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHashemi H, et al. Distribution of Corneal Volume and Its Associated Factors in an Elderly Population: Tehran Geriatric Eye Study. Cornea. 2023;42(9):1092\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFontana ST, Brubaker RF. Volume and depth of the anterior chamber in the normal aging human eye. Arch Ophthalmol. 1980;98(10):1803\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCook CA, et al. Aging of the human crystalline lens and anterior segment. Vis Res. 1994;34(22):2945\u0026ndash;54.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"boph","sideBox":"Learn more about [BMC Ophthalmology](http://bmcophthalmol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/boph","title":"BMC Ophthalmology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7851657/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7851657/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Purpose: To evaluate anterior and posterior corneal surfaces and anterior segment parameters in the Turkish population using Pentacam, and to analyze age-related changes.\nMethods: Corneal topographies of patients without ocular pathology, admitted to the Ophthalmology Outpatient Clinic of xxxx Faculty of Medicine, were retrospectively reviewed. Measurements included anterior and posterior keratometry (K1, K2, Kmean), astigmatism values and axes, radii of curvature (Rflat, Rsteep, Rmean), asphericity (Q value), thinnest corneal thickness, corneal volume, anterior chamber volume (ACV), and anterior chamber depth (ACD). Patients were divided into four groups: 3–19, 20–39, 40–59, and ≥60 years. Age-related variations in parameters were analyzed.\nResults: A total of 1202 eyes of 601 patients (49.1% male, 50.9% female; mean age 35.3 ± 23.1 years) were included. Significant differences were found in anterior K1 and Kmean among the 20–39, 40–59, and ≥60 groups, and in anterior K2 between the 20–39 group and both younger and older groups. Posterior K2 differed between the 3–19 and ≥60 groups. Anterior and posterior radii increased in the 20–39 group but declined later, whereas posterior Rsteep rose with age. With-the-rule astigmatism decreased on the anterior surface but increased posteriorly, while against-the-rule and oblique astigmatism rose with age. Corneal asphericity showed more negative Q values after 40 years. ACV, ACD, corneal volume, and thinnest corneal thickness decreased progressively with age.\nConclusions: The Turkish cornea shows age-related changes, becoming more prolate with age, with astigmatism shifts and reductions in chamber and corneal volumes.\nKey Words: Cornea, Corneal Topography, Pentacam.\n \n ","manuscriptTitle":"Age-related Changes in Corneal Parameters in the Turkish Population: A Pentacam-based Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-08 11:37:10","doi":"10.21203/rs.3.rs-7851657/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-12-19T08:49:17+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-17T18:47:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"245334710109508667606549999352154295878","date":"2025-12-09T04:53:07+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"35069353537021710472075134692324159840","date":"2025-12-07T05:49:48+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-06T14:28:06+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"75996949177175549332524785365744408497","date":"2025-12-06T07:07:19+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"104696282276297876248206145709906736168","date":"2025-12-06T06:59:40+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"144311251969654446498074850342572483805","date":"2025-12-06T05:27:32+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"197008065158010830080121464090269487022","date":"2025-12-05T12:12:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"240106398866528508614931610837743351848","date":"2025-12-04T04:42:59+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-12-04T04:35:51+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-11-24T07:38:15+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-10-31T09:39:31+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-30T17:16:56+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Ophthalmology","date":"2025-10-30T17:13:19+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"boph","sideBox":"Learn more about [BMC Ophthalmology](http://bmcophthalmol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/boph","title":"BMC Ophthalmology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"28593a6f-f4bd-4c6b-88cf-b49cf64cb3ba","owner":[],"postedDate":"December 8th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-04-23T12:40:04+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-08 11:37:10","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7851657","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7851657","identity":"rs-7851657","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}