Corneal Higher-order Aberrations in Corneal Endothelial Decompensation Secondary to Obstetric Forceps Injury

Corneal Higher-order Aberrations in Corneal Endothelial Decompensation Secondary to Obstetric Forceps Injury | 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 Help Center Sign In Submit a Preprint Cite Share Download PDF Article Corneal Higher-order Aberrations in Corneal Endothelial Decompensation Secondary to Obstetric Forceps Injury Hirotsugu Kasamatsu, Yukari Yagi-Yaguchi, Takefumi Yamaguchi, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-2425903/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 03 Apr, 2023 Read the published version in Scientific Reports → Version 1 posted 10 You are reading this latest preprint version Abstract Forceps corneal injuries during infant delivery cause Descemet membrane (DM) breaks, that cause corneal astigmatism and corneal endothelial decompensation. The aim of this study is to characterise corneal higher-order aberrations (HOAs) and corneal topographic patterns in corneal endothelial decompensation due to obstetric forceps injury. This retrospective study included 23 eyes of 21 patients (54.0 ± 9.0 years old) with forceps corneal injury, and 18 healthy controls. HOAs and coma aberrations were significantly larger in forceps injury (1.05 [0.76 to 1.98] µm, and 0.83 [0.58 to 1.69], respectively) than in healthy controls (0.10 [0.08 to 0.11], and 0.06 [0.05 to 0.07], respectively, both P < 0.0001). Patient visual acuity was positively correlated with coma aberration ( r s = 0.482, P = 0.023). The most common topographic patterns were those of protrusion and regular astigmatism (both, six eyes, 26.1%), followed by asymmetric (5 eyes, 21.7%), flattening (4 eyes, 17.4%). These results indicate that increased corneal HOAs are associated with decreased visual acuity in corneal endothelial decompensation with DM breaks and corneal topography exhibits various patterns in forceps injury. Health sciences/Medical research Health sciences/Diseases/Eye diseases Forceps corneal injury higher-order aberrations corneal astigmatism Descemet’s membrane rupture corneal endothelial decompensation Figures Figure 1 Figure 2 Introduction Forceps corneal injuries during infant delivery were first reported by Noyes et al. in 1895. 1 Forceps corneal injury is characterised by Descemet membrane (DM) breaks, occurring vertically, and obliquely oriented striae on the inner corneal surface. After delivery, corneal oedema is obvious, however, spontaneously resolves within a few weeks or months, leaving visible edges of the break and a clear cornea. These breaks have been associated with various degrees of asymmetric astigmatism, and deep amblyopia. 2 Slowly progressive endothelial cell loss and secondary corneal decompensation ensue, causing corneal oedema and bullous keratopathy in the fourth or fifth decade of life. 3 Forceps corneal injury is responsible for 1.6% of all bullous keratopathy cases, 4 and 2.0% of the indications for Descemet stripping automated endothelial keratoplasty (DSAEK) in Japan. 5 Although several case studies have reported successful DSAEK for the treatment of bullous keratopathy due to forceps corneal injury, 6–8 careful planning is needed because amblyopia, high levels of astigmatism, an irregular posterior corneal surface, and severe corneal oedema may be present. Furthermore, there are intraindividual differences in these properties. However, the structural/optical features of the cornea have not been well investigated. Recent technological advances have allowed the acquisition of images and precise information on the cornea and the anterior portion of the eye. 9–12 Anterior segment optical coherence tomography (AS-OCT) is used to obtain precise data even in opaque corneas. 12,13 Using AS-OCT, we recently reported that presence of higher-order aberrations (HOAs) were significantly associated with reduction in visual acuity in eyes with severe corneal opacity, such as herpes simplex keratitis, 14 corneal stromal dystrophies, 15 Stevens-Johnson syndrome. 16 We observed that patients with bullous keratopathy due to forceps corneal injury exhibited several typical corneal topographic patterns, similar to those seen in other corneal diseases. 14–16 Thus, we hypothesized that forceps corneal injury causes increased HOAs, leading to decreased visual acuity, and exhibits several topographic patterns; when evaluating the influence of corneal optical property on visual function and determining corneal transplantation in eyes with forceps corneal injury, HOAs and topographic patterns can be an objective biomarker. In the current study, we first calculated corneal HOAs in eyes with bullous keratopathy due to forceps corneal injury and compared them with HOAs present in healthy eyes. Second, we characterised the topographic patterns of bullous keratopathy due to forceps corneal injury. Third, we evaluated the correlation between visual acuity and HOAs in these eyes, with the aim of identifying the effects of HOAs on visual acuity. Fourth, we analysed HOAs before and after DSAEK for the treatment of forceps corneal injury. Methods Patients This retrospective consecutive case series was performed in accordance with the principles of the Declaration of Helsinki, and the study protocol was approved by the Institutional Ethics Review Board of Tokyo Dental College Ichikawa General Hospital (I-15-51). Our institutional review board waived the requirement for informed consent, and the patient data were anonymised before access and/or analysis. This study included 23 eyes of 21 consecutive patients (54.0 ± 9.0 [mean ± standard deviation: SD] years) who had been diagnosed with corneal endothelial decompensation due to forceps corneal injury at Ichikawa General Hospital from October 2009 to November 2018, and 18 eyes of age matched healthy control participants (Supplementary table 1). We excluded patients with corneal scarring caused by other conditions, such as trauma or infectious keratitis, and history of ocular surface surgeries that could induce corneal astigmatism, such as for pterygium, glaucoma surgery and corneal transplantation. The mean age of the participants in the healthy control group was 55.1 ± 18.5 years. Data analysis Routine testing of all patients included slit-lamp microscopy, fundus, and best-spectacle corrected visual acuity (BSCVA) examinations at the time of diagnosis. Visual acuity was measured using the standard Landolt optotype. The measured decimal acuity was converted to logarithm of the minimum angle of resolution (logMAR) units using a Visual Acuity Conversion Chart. We defined amblyopia as reduced visual acuity with BSCVA below 20/20 without pathological causes such as cataracts and disorders in the macula and optic nerve. 17 A blinded observer (HK) graded the extent of corneal opacity and severity of bullous keratopathy based on the slit-lamp examination results according to a previously described system as follows: 18 corneal opacity grade; 0, clear or trace haze; grade 1, mild opacity; grade 2, moderately dense opacity partially obscuring the details of the iris; and grade 3, severely dense opacity obscuring the details of the intraocular structures. The severity of bullous keratopathy was defined as follows: stage 1, slight stromal oedema or increased corneal thickness due to reduction in corneal endothelial cells; stage 2, stromal oedema with DM folds; stage 3, stromal oedema and DM folds with apparent epithelial bullae; stage 4, stromal scarring and corneal neovascularization. Anterior segment optical coherence tomography AS-OCT was used to evaluate the corneal structure in eyes with forceps corneal injury as reported previously. 14–16 In brief, the CASIA system (SS-1000, Tomey, Nagoya, Japan) corrected distortions in the AS-OCT images based on the refractive index of the anterior surface. Two corneal specialists (HK and TY) carefully checked all AS-OCT images to ensure that the surface digitalization recognized by the automated inbuilt software was correct. The anterior and posterior corneal surfaces were reconstructed as a three-dimensional model from the corneal height data. The anterior, posterior, and total corneal aberrations at the diameters of 4mm and 6mm were calculated separately with the installed ray tracing software, version 5.1. The refractive indices of the cornea and aqueous humor were set to 1.376 and 1.336, respectively. The wavefront aberration was expanded with normalized Zernike polynomials up to the 8th order. HOA was defined as the root mean square (RMS) of the 3rd - to 8th -order Zernike coefficients as follows.[ 18 ] Spherical aberration (SA) was defined as the RMS of Z 4 0 (spherical aberration) and Z 6 0 (secondary spherical aberration). Coma aberration was defined as the RMS of Z 3 − 1 and Z 3 1 . Classification of corneal shapes into five topographic patterns Topographic patterns were categorised into five types, i.e., regular astigmatism, asymmetric, protrusion, flattening, and posterior irregular with minimal anterior irregularity, as previously reported. 14–16 Briefly, the AS-OCT images of corneas with forceps corneal injury showed a high degree of irregular astigmatism on the anterior and posterior surfaces. The regular astigmatism pattern was defined as regular astigmatism with an astigmatism power of ≥ 3 diopter. The asymmetric pattern was defined as a mirror-image with blue and red asymmetric color on the topographic map of the anterior surface, half with a keratometric value of ≥ 45 diopters and the other half with a keratometric value of ≤ 40 diopters. The protrusion pattern was defined as a centrally steep zone with a keratometric value of ≥ 50 diopters on the anterior surface. The flattening pattern was defined as a flattened cornea with a keratometric value of ≤ 35 diopters on the anterior surface. The posterior irregular pattern with minimal anterior surface changes was considered when there were minimal changes in the anterior surface. Descemet stripping automated endothelial keratoplasty Among 23 eyes, 11 patients (11 eyes) underwent DSAEK. DSAEK was performed using double-glide technique. Briefly, after sub-Tenon anesthesia with injection of 2% lidocaine, a 4.5-mm temporal corneoscleral incision was made. Descemet stripping was performed with a reverse-bent Sinsky hook (Asico, Westmont, IL, USA). The recipient’s endothelium and Descemet’s membrane were carefully removed using forceps. Pre-cut donor grafts were trephinated and the endothelial surface of the donor lenticle was coated with a small amount of viscoelastic material. Donor tissue was gently inserted into the anterior chamber using a Busin glide (Asico) and Shimazaki forceps (Inami, Tokyo, Japan). Air was carefully injected into the anterior chamber to unfold the graft. At 10 min after air injection, half of the air was replaced by balanced salt solution (Alcon, Fort Worth, TX, USA). At the end of the surgery, 2mg subconjunctival betamethasone was administered. Corneal HOAs were evaluated 3 months after DSAEK. Statistical analysis The data were analysed using the Prism software (ver. 6.04 for Windows; GraphPad Software, Inc., San Diego, CA, USA). The D’Agostino and Pearson omnibus normality test was used to assess whether the data showed a normal distribution. To compare the differences in HOAs between healthy subjects and patients with forceps corneal injury, the Mann-Whitney test was used. Spearman’s correlations were performed to determine the association between logMAR and each parameter including coma aberrations and HOAs within 4-mm and 6mm diameters, opacity grade, bullous stage, and CCT. To comparison between before and after DSAEK for corneal higher-order aberrations, Wilcoxon singed rank tests were used. All tests were 2-tailed and a P value less than 0.05 was considered to indicate statistical significance. Results Patient demographics Patient demographics are shown in Supplementary table 1. Of 23 eyes with forceps corneal injuries, 22 (95.7%) patients had amblyopia. The direction of DM break on slit photographs was horizontal (1–30°, 151–180°) in six eyes (26.1%), oblique (31–60°, 121–150°) in 12 eyes (52.2%), and vertical (61–120°) in five eyes (21.7%). The direction of DM breaks was identical to that of the corneal astigmatism axis of the steep meridian in 14 of 23 eyes (Fig. 1 , 60.9%), whereas the direction of DM break was not associated with that of the corneal astigmatism axis of the steep meridian in the nine other eyes because of severe corneal deformations, such as asymmetric changes or protrusion. Higher-order aberrations in forceps corneal injuries Compared with the healthy control eyes, all HOA parameters, including HOAs, SA, and coma aberrations (total / anterior / posterior, 4mm / 6mm) were significantly higher in eyes with forceps corneal injury (Table 1 , all P < 0.001). Total HOAs were larger than those of anterior surface in forceps corneal injury. Table 1 Corneal Higher-order Aberrations in Bullous Keratopathy due to Forceps Injuries Forceps Injuries (23 eyes) Healthy controls (18 eyes) P value * HOA 4mm Total 1.05 (0.76, 1.98) 0.10 (0.08, 0.11) < 0.001 Anterior 0.92 (0.81, 1.69) 0.10 (0.09, 0.11) < 0.001 Posterior 0.50 (0.45, 0.77) 0.02 (0.02, 0.02) < 0.001 HOA (6mm) Total 1.79 (1.48, 2.83) 0.19 (0.16, 0.21) < 0.001 Anterior 2.03 (1.52, 2.82) 0.19 (0.17, 0.22) < 0.001 Posterior 0.87 (0.73, 1.06) 0.06 (0.05, 0.07) < 0.001 SA (4mm) Total 0.72 (0.43, 1.03) 0.07 (0.05, 0.08) < 0.001 Anterior 0.61 (0.40, 0.92) 0.08 (0.06, 0.09) < 0.001 Posterior 0.34 (0.20, 0.45) 0.02 (0.01, 0.02) < 0.001 SA (6mm) Total 1.00 (0.75, 1.51) 0.13 (0.11, 0.15) < 0.001 Anterior 0.99 (0.77, 1.43) 0.14 (0.12, 0.16) < 0.001 Posterior 0.42 (0.35, 0.57) 0.05 (0.05, 0.05) < 0.001 Coma (4mm) Total 0.83 (0.58, 1.69) 0.06 (0.05, 0.07) < 0.001 Anterior 0.72 (0.53, 1.48) 0.06 (0.05, 0.07) < 0.001 Posterior 0.41 (0.30, 0.62) 0.01 (0.01, 0.01) < 0.001 Coma (6mm) Total 1.35 (1.17, 2.57) 0.12 (0.10, 0.16) < 0.001 Anterior 1.72 (1.31, 2.62) 0.13 (0.11, 0.18) < 0.001 Posterior 0.72(0.55, 0.96) 0.02(0.02, 0.03) < 0.001 median (IQR) HOA = higher order aberration; IQR = interquartile range; SA = spherical aberration *Mann-Whitney U test Correlations among visual acuities, coma aberration and opacity grade LogMAR visual acuity was significantly positively correlated with coma aberrations in the 4-mm zone of the anterior surface, and 6-mm zones of the total cornea and anterior surface (Table 2 , r s = 0.454, P = 0.03; r s = 0.482, P = 0.02; r s = 0.504, P = 0.02, respectively). LogMAR visual acuity was positively correlated with the opacity grade and severity of the bullous stage ( r s = 0.700, P = 0.0003; r s = 0.675, P = 0.0006, respectively), not with the CCT (r s = 0.175, P = 0.435). Table 2 Correlation between visual acuity, coma aberration, HOA, opacity grade, bullous stage, and CCT. 4 mm Zone 6 mm Zone Coma Aberration Total cornea 0.28 (0.21) 0.482 (0.02) Anterior surface 0.454 (0.03) 0.504 (0.02) Posterior surface -0.166 (0.46) -0.018 (0.94) HOA Total cornea 0.321 (0.14) 0.383 (0.071) Anterior surface 0.374 (0.08) 0.471 (0.02) Posterior surface -0.014 (0.95) 0.056 (0.80) Opacity grade a 0.700 (< 0.001) Bullous stage b 0.675 (< 0.001) CCT 0.175 (0.43) HOA = higher order aberration; IQR = interquartile range; SA = spherical aberration. a corneal opacity grade; 0, clear or trace haze; grade 1, mild opacity; grade 2, moderately dense opacity partially obscuring the details of the iris; and grade 3, severely dense opacity obscuring the details of the intraocular structures. b The severity of bullous keratopathy was defined as follows: stage 1, slight stromal edema or increased corneal thickness due to reduction in corneal endothelial cells; stage 2, stromal edema with DM folds; stage 3, stromal edema and DM folds with apparent epithelial bullae; stage 4, stromal scarring and corneal neovascularization. Data are expressed as Spearman's correlation coefficient r s ( P ). Bold numbers indicate P < 0.05. Corneal topographical map patterns Representative cases are shown in Fig. 2 . Protrusion and regular astigmatism patterns were identified as the most common alterations in the topographic maps (both, 6 eyes, 26.1%), followed by asymmetric pattern (5 eyes, 21.7%), flattening pattern (4 eyes, 17.4%), and posterior irregular pattern with minimal anterior surface changes (2 eyes, 8.7%). Corneal Higher-order Aberrations Before and After DSAEK After DSAEK, logMAR was improved from 1.52 (0.61 to1.70) (median [IQR]) to 0.52 (0.40 to 0.76) ( P < 0.01, Table 3 ). Corneal HOAs was significantly improved after DSAEK (Table 3 ). Although there were no statistically significant correlations presumably due to the small number of subjects, logMAR after DSAEK was weakly correlated with corneal HOA (6mm, r s = 0.59, P = 0.06). Table 3 Corneal Higher-order Aberrations Before and After DSAEK in Eyes with Bullous Keratopathy due to Forceps Injuries Before DSAEK (11 eyes) Post DSAEK (11 eyes) P value * BSCVA (logMAR) 1.52 (0.61 to1.70) 0.52 (0.40 to 0.76) < 0.01 HOA 4mm Total 1.01 (0.93, 1.32) 0.79 (0.61, 0.87) 0.02 Anterior 0.91 (0.84, 1.09) 0.62 (0.58, 0.81) 0.02 Posterior 0.49 (0.45, 0.60) 0.31 (0.23, 0.43) 0.08 HOA (6mm) Total 1.63 (1.48, 2.09) 1.43 (1.19, 1.96) 0.70 Anterior 2.00 (1.62, 2.19) 1.60 (1.30, 2.03) 0.20 Posterior 0.77 (0.59, 0.85) 0.70 (0.66, 0.99) 0.32 SA (4mm) Total 0.72 (0.50, 0.92) 0.49 (0.32, 0.52) 0.04 Anterior 0.61 (0.58, 0.81) 0.41 (0.27, 0.42) < 0.01 Posterior 0.39 (0.22, 0.45) 0.22 (0.17, 0.28) 0.16 SA (6mm) Total 1.35 (1.27, 1.53) 0.72 (0.64, 0.90) 0.55 Anterior 0.98 (0.80, 1.24) 0.66 (0.56, 0.78) 0.01 Posterior 0.39 (0.35, 0.51) 0.44 (0.39, 0.52) 0.35 Coma (4mm) Total 0.77 (0.61, 0.91) 0.63 (0.47, 0.69) 0.04 Anterior 0.70 (0.54, 0.90) 0.56 (0.46, 0.68) 0.11 Posterior 0.36 (0.28, 0.47) 0.22 (0.16, 0.30) 0.10 Coma (6mm) Total 1.35 (1.27, 1.53) 1.24 (0.99, 1.74) 0.77 Anterior 1.72 (1.35, 1.92) 1.49 (1.09, 1.92) 0.47 Posterior 0.63 (0.40, 0.73) 0.55 (0.47, 0.60) 0.30 median (IQR) BSCVA = best-spectacle corrected visual acuity; HOA = higher order aberration; IQR = interquartile range; logMAR = logarithm of minimal angle resolution; SA = spherical aberration. *Wilcoxon rank sum test Bold numbers indicate P < 0.05. Discussion Forceps corneal injury causes vision loss later in life and pain due to epithelial bulla formation associated with bullous keratopathy. As it is a rare disease, accounting for only 1–2% of bullous keratopathy cases, 4 the clinical subtypes and degrees of astigmatism in eyes with forceps corneal injury remains poorly understood. The current study showed increased corneal HOAs, SAs and coma aberrations in eyes with bullous keratopathy due to forceps corneal injury. This study also showed that coma aberrations were associated with decreased visual acuity. To our knowledge, this was the largest case series to have quantified corneal aberrations and clinical data in eyes with forceps injuries. Owing to the small number of cases, previous studies have included samples of only one to 12 patients. 1–3,6−8,19−26 Therefore, it has been difficult to accurately characterise clinical features such as the degree of regular and irregular astigmatism, incidence of amblyopia, corneal structure and optical properties. For example, since Lloyd reported six forceps corneal injuries in which the left eye was the affected eye in all cases, 27 it was believed that the left eye is often traumatised during the process of passing through the birth canal; 27 however, in this study, the injured eye was more often the right (57.1%) than the left (42.9%). Forceps corneal injury causes amblyopia because of a high degree of corneal astigmatism. 7 In this case series, 22 of 23 patient eyes had amblyopia. Furthermore, we found that the direction of DM breaks coincided with the steep meridian of the cornea in 14 of 23 eyes (60.9%) with apparent astigmatism axis with regular and flattening topographic patterns, whereas in eyes with asymmetric and protrusion patterns, there was no association with the astigmatism axis. Interestingly, the topographic elevation map of the anterior and posterior surface showed that the corneal posterior shift was located exactly in the area of the DM breaks (Fig. 1 ), suggesting that DM breaks directly cause astigmatism in the posterior surface. When comparing the HOAs of the total cornea (4 mm) based on our previous studies on various corneal diseases (Supplementary Fig. 1) 14–16,28 corneal HOAs differed among various corneal diseases with large intraindividual differences (large standard deviation). Notably, visual acuity was significantly correlated with corneal HOAs in all corneal diseases, except granular corneal dystrophy type 2, where HOAs were not increased. 15 In forceps corneal injuries, the mean HOA was much higher than that in other diseases. Moreover, it is noteworthy that the corneal HOAs of the posterior surface were significantly larger in eyes with forceps corneal injury, this is related to larger HOAs of the total cornea. Theoretically, in healthy eyes, where the posterior and anterior surfaces are parallel to each other, aberrations of the posterior surface tend to compensate for those of the anterior surface, resulting in fewer corneal HOAs in the total cornea. 29 The disruption of parallelism between the anterior and posterior surfaces in forceps corneal injuries may cause the lack of compensation, leading to increased total corneal HOAs. Measurement of corneal HOAs is clinically relevant because it is correlated with visual acuity. We believe that corneal HOAs can comprise a universal diagnostic biomarker for decision-making in corneal transplantation, and can be applied to various corneal diseases, including forceps corneal injury. In the current study, we found that both the posterior surface, where the DM scroll is located, and the anterior surface had large aberrations in eyes with forceps corneal injury (Fig. 2 , Table 1 ). When considering surgical indications, DASEK is a standard surgical treatment for forceps corneal injury because of its several advantages over penetrating keratoplasty (PKP), including rapid visual recovery, biomechanical properties, and integrity. 30–32 However, in DSAEK, large amounts of HOAs on the anterior surface can remain after surgery and adversely effect on visual acuity. In the current case series, 18 patients underwent corneal transplantation (PKP in 4 eyes and DSAEK in 14 eyes). Although logMAR visual acuity significantly improved from 1.70 (IQR, 0.7 to 1.85) to 1.00 (IQR, 0.52 to 1.70) after corneal transplantation, the improvement in visual acuity was limited especially in patients with large HOAs in the anterior surface. The residual HOAs after DSAEK were influenced by the preoperative HOAs due to stromal deformation in forceps corneal injury. Thus, we need to evaluate corneal HOAs, when deciding whether to perform PKP or DSAEK in eyes with forceps corneal injury. This study had several limitations. First, the patient age at onset of bullous keratopathy due to forceps corneal injury could have caused bias. Age has been reported to affect visual function, refraction, and astigmatism. 33 However, age-related HOA changes are minor, compare with the increase in corneal HOAs in eyes with forceps corneal injury. Therefore, we believe that the age-related bias was minimal. Second, there might be some differences in the refractive indices between normal corneas and bullous keratopathy, which may have influenced our estimated HOAs. Theoretically, corneal oedema can affect refractive index and errors in refractive power of the cornea by less than 5%, 34,35 minimally influencing the results of the current study. Third, 22 eyes (95.7%) in current study had amblyopia. However, a correlation between visual acuity and corneal aberrations was observed, despite the presence of amblyopia. In conclusion, Descemet’s scrolls in eyes with forceps injuries induce morphometric changes in the anterior and posterior surfaces, leading to increased corneal HOAs, SAs and coma of the total cornea and anterior and posterior surfaces. We also classified irregular astigmatism patterns into five types, based on the corneal topographic map. The most common patterns are protrusion and regular astigmatism. Furthermore, increases in coma were significantly correlated with visual acuity, indicating that coma may be a biomarker for assessing visual function in eyes with forceps corneal injuries. Declarations All authors certify that they have no involvement with any entity or organization with any financial interest in the subject matter or materials discussed in the manuscript. Financial support: None Meeting presentation: We presented this study in ARVO2022. Acknowledgment H.K. had full access to all the data in the present study and takes responsibility for its integrity and accuracy of the data analyses. H.K. and T.Y. designed the study. H.K., Y.Y.Y., T.Y., S.N., T.M., and J.S. acquired and interpreted data. H.K., T.Y., and J.S. drafted the manuscript. All authors reviewed and approved the manuscript. Data availability statement The datasets used and/or analysed during the current study available from the corresponding author on reasonable request. References Noyes HD. 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The contribution of the posterior surface to the coma aberration of the human cornea. J Vis 7 , 10.1-8 (2007). Price FW Jr, Price MO. Descemet's stripping with endothelial keratoplasty in 200 eyes: Early challenges and techniques to enhance donor adherence. J Cataract Refract Surg 32 , 411–418 (2006). Price MO, Price FW Jr. Descemet's stripping with endothelial keratoplasty: comparative outcomes with microkeratome-dissected and manually dissected donor tissue. Ophthalmology 113 ,1936–1942 (2006). Koenig SB, Covert DJ. Early results of small-incision Descemet's stripping and automated endothelial keratoplasty. Ophthalmology 114 , 221–226 (2007). Amano S, Amano Y, Yamagami S, et al. Age-related changes in corneal and ocular higher-order wavefront aberrations. Am J Ophthalmol. 137 , 988–992 (2004). Kim YL, Walsh JT Jr, Goldstick TK, Glucksberg MR. Variation of corneal refractive index with hydration. Phys Med Biol 49 , 859–868 (2004). Meek KM, S Dennis, Khan S. Changes in the refractive index of the stroma and its extrafibrillar matrix when the cornea swells. Biophys J 85 , 2205–2012 (2003). Additional Declarations No competing interests reported. Supplementary Files Supplementarydata.xlsx Supplementaryfile.docx Cite Share Download PDF Status: Published Journal Publication published 03 Apr, 2023 Read the published version in Scientific Reports → Version 1 posted Editorial decision: Major revision 20 Feb, 2023 Reviews received at journal 19 Feb, 2023 Reviewers agreed at journal 14 Feb, 2023 Reviews received at journal 25 Jan, 2023 Reviewers agreed at journal 16 Jan, 2023 Reviewers invited by journal 16 Jan, 2023 Editor assigned by journal 16 Jan, 2023 Editor invited by journal 12 Jan, 2023 Submission checks completed at journal 12 Jan, 2023 First submitted to journal 29 Dec, 2022 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-2425903","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":167146604,"identity":"576d2390-bfe9-47a0-8860-83eacf804e90","order_by":0,"name":"Hirotsugu Kasamatsu","email":"","orcid":"","institution":"Tokyo Dental College Ichikawa General Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Hirotsugu","middleName":"","lastName":"Kasamatsu","suffix":""},{"id":167146607,"identity":"cf117e4a-e4d1-4f24-be86-8b3fc16d73ad","order_by":1,"name":"Yukari Yagi-Yaguchi","email":"","orcid":"","institution":"Tokyo Dental College Ichikawa General Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yukari","middleName":"","lastName":"Yagi-Yaguchi","suffix":""},{"id":167146608,"identity":"a8302ca7-5f8d-44d4-98b2-224153655022","order_by":2,"name":"Takefumi Yamaguchi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA5ElEQVRIiWNgGAWjYBCDBDYG5gMMPFAOkVrY2BIbSNPCwMZjCNOCHxgcP5348WubXR6ffM/3B29qGOT5GxiePcCr5UzuZmnZtuRiNjbejY1zjjEYzjjAkG6AV8uB3A3Skm0HEtuAWpp5GxgYNzAwpEng1XL+7ebfEC08D0Fa7AlruZG7TfIjRAsjSEsiQS2SN95us2Y4lwzUkmY4c84xieQZhwn4he987uabP8rsEuc3H37w4U2NjW1/e0/aA3xaFA4wMDAjRYcEiJuGTweDfAMDA+MPVDH2Y3i1jIJRMApGwYgDAEauTKvnfVygAAAAAElFTkSuQmCC","orcid":"","institution":"Tokyo Dental College Ichikawa General Hospital","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Takefumi","middleName":"","lastName":"Yamaguchi","suffix":""},{"id":167146610,"identity":"c6b24eb5-9be1-4d9b-b8d2-538f80fe72ff","order_by":3,"name":"Sota Nishisako","email":"","orcid":"","institution":"Tokyo Dental College Ichikawa General Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Sota","middleName":"","lastName":"Nishisako","suffix":""},{"id":167146613,"identity":"fb30b55a-e0ba-450f-bfe1-85e09176b76f","order_by":4,"name":"Toshinori Murata","email":"","orcid":"","institution":"Shinshu University School of Medicine","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Toshinori","middleName":"","lastName":"Murata","suffix":""},{"id":167146614,"identity":"db18e17e-ed8d-4166-97fd-36a6f9c2352a","order_by":5,"name":"Jun Shimazaki","email":"","orcid":"","institution":"Tokyo Dental College Ichikawa General Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Jun","middleName":"","lastName":"Shimazaki","suffix":""}],"badges":[],"createdAt":"2022-12-29 15:44:22","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-2425903/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-2425903/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41598-023-32683-5","type":"published","date":"2023-04-03T20:22:30+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":31545432,"identity":"537ca28c-5243-40ba-8198-cf99d7ecde7b","added_by":"auto","created_at":"2023-01-13 15:43:16","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1615105,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eDirection of Descemet break and astigmatism axis.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCase1 (A-D) is a 51-year-old woman, a Descemet membrane (DM) break appears obliquely present (A: arrow heads). Case2 (E-H) is a 69-year-old man, a Descemet membrane (DM) break appears horizontal present (E: arrow heads). Case 3 (I-L) is a 67-year-old woman, a Descemet membrane (DM) break appears vertical present (I: arrow heads). The topographic elevation map shows a blue area on the anterior (B, F, J) and posterior corneal surfaces (C, G, K) in the area with the DM break (A, E, I). Those blue areas are associated with the corneal astigmatism axis (D, H, L). In the current study, the direction of the DM breaks was identical to that of the corneal astigmatism axis in 14 of 23 eyes (60.9%).\u003c/p\u003e","description":"","filename":"Fig1.png","url":"https://assets-eu.researchsquare.com/files/rs-2425903/v1/3cd373268d4644ebead1c9ef.png"},{"id":31545433,"identity":"bf8db343-e913-4848-b247-fd4225861fd1","added_by":"auto","created_at":"2023-01-13 15:43:16","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":1346782,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eRepresentative cases of forceps injuries.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eRepresentative slit-lamp photographs (A–E), AS-OCT images (F–J), and topographic maps of the anterior (K-O) and posterior surfaces (P–T) of eyes with bullous keratopathy due to forceps corneal injuries. Topographic maps are characterised into five patterns: regular astigmatism (A, F, K and P), asymmetry (B, G, L, and Q), protrusion (C, H, M, and R), flat (D, I, N, and S), and posterior irregular patterns (E, J, O, and T).\u003c/p\u003e","description":"","filename":"Fig2.png","url":"https://assets-eu.researchsquare.com/files/rs-2425903/v1/e62ef6650c18d9c67695ca1b.png"},{"id":44724348,"identity":"3b69b469-846b-426c-b2e0-e8cfa2ef14aa","added_by":"auto","created_at":"2023-10-16 20:29:28","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2900861,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-2425903/v1/b3b0693f-cfc6-45fc-b33d-9989593369c0.pdf"},{"id":31545434,"identity":"9ec1fa7b-a4d0-496a-9002-5c3e08d63374","added_by":"auto","created_at":"2023-01-13 15:43:16","extension":"xlsx","order_by":5,"title":"","display":"","copyAsset":false,"role":"supplement","size":138726,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementarydata.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-2425903/v1/9c2a6cf4a4716d5b8dfdfc2b.xlsx"},{"id":31545435,"identity":"a2c0c1e1-4036-452d-83f4-2a7613a4c13f","added_by":"auto","created_at":"2023-01-13 15:43:16","extension":"docx","order_by":6,"title":"","display":"","copyAsset":false,"role":"supplement","size":260994,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementaryfile.docx","url":"https://assets-eu.researchsquare.com/files/rs-2425903/v1/2cf287c91a647ef12e431a4b.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Corneal Higher-order Aberrations in Corneal Endothelial Decompensation Secondary to Obstetric Forceps Injury","fulltext":[{"header":"Introduction","content":"\u003cp\u003eForceps corneal injuries during infant delivery were first reported by Noyes et al. in 1895.\u003csup\u003e1\u003c/sup\u003e Forceps corneal injury is characterised by Descemet membrane (DM) breaks, occurring vertically, and obliquely oriented striae on the inner corneal surface. After delivery, corneal oedema is obvious, however, spontaneously resolves within a few weeks or months, leaving visible edges of the break and a clear cornea. These breaks have been associated with various degrees of asymmetric astigmatism, and deep amblyopia.\u003csup\u003e2\u003c/sup\u003e Slowly progressive endothelial cell loss and secondary corneal decompensation ensue, causing corneal oedema and bullous keratopathy in the fourth or fifth decade of life.\u003csup\u003e3\u003c/sup\u003e Forceps corneal injury is responsible for 1.6% of all bullous keratopathy cases,\u003csup\u003e4\u003c/sup\u003e and 2.0% of the indications for Descemet stripping automated endothelial keratoplasty (DSAEK) in Japan.\u003csup\u003e5\u003c/sup\u003e Although several case studies have reported successful DSAEK for the treatment of bullous keratopathy due to forceps corneal injury,\u003csup\u003e6\u0026ndash;8\u003c/sup\u003e careful planning is needed because amblyopia, high levels of astigmatism, an irregular posterior corneal surface, and severe corneal oedema may be present. Furthermore, there are intraindividual differences in these properties. However, the structural/optical features of the cornea have not been well investigated.\u003c/p\u003e \u003cp\u003eRecent technological advances have allowed the acquisition of images and precise information on the cornea and the anterior portion of the eye.\u003csup\u003e9\u0026ndash;12\u003c/sup\u003e Anterior segment optical coherence tomography (AS-OCT) is used to obtain precise data even in opaque corneas.\u003csup\u003e12,13\u003c/sup\u003e Using AS-OCT, we recently reported that presence of higher-order aberrations (HOAs) were significantly associated with reduction in visual acuity in eyes with severe corneal opacity, such as herpes simplex keratitis,\u003csup\u003e14\u003c/sup\u003e corneal stromal dystrophies,\u003csup\u003e15\u003c/sup\u003e Stevens-Johnson syndrome.\u003csup\u003e16\u003c/sup\u003e We observed that patients with bullous keratopathy due to forceps corneal injury exhibited several typical corneal topographic patterns, similar to those seen in other corneal diseases.\u003csup\u003e14\u0026ndash;16\u003c/sup\u003e Thus, we hypothesized that forceps corneal injury causes increased HOAs, leading to decreased visual acuity, and exhibits several topographic patterns; when evaluating the influence of corneal optical property on visual function and determining corneal transplantation in eyes with forceps corneal injury, HOAs and topographic patterns can be an objective biomarker. In the current study, we first calculated corneal HOAs in eyes with bullous keratopathy due to forceps corneal injury and compared them with HOAs present in healthy eyes. Second, we characterised the topographic patterns of bullous keratopathy due to forceps corneal injury. Third, we evaluated the correlation between visual acuity and HOAs in these eyes, with the aim of identifying the effects of HOAs on visual acuity. Fourth, we analysed HOAs before and after DSAEK for the treatment of forceps corneal injury.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n\u003ch2\u003ePatients\u003c/h2\u003e\n\u003cp\u003eThis retrospective consecutive case series was performed in accordance with the principles of the Declaration of Helsinki, and the study protocol was approved by the Institutional Ethics Review Board of Tokyo Dental College Ichikawa General Hospital (I-15-51). Our institutional review board waived the requirement for informed consent, and the patient data were anonymised before access and/or analysis. This study included 23 eyes of 21 consecutive patients (54.0\u0026thinsp;\u0026plusmn;\u0026thinsp;9.0 [mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation: SD] years) who had been diagnosed with corneal endothelial decompensation due to forceps corneal injury at Ichikawa General Hospital from October 2009 to November 2018, and 18 eyes of age matched healthy control participants (Supplementary table 1). We excluded patients with corneal scarring caused by other conditions, such as trauma or infectious keratitis, and history of ocular surface surgeries that could induce corneal astigmatism, such as for pterygium, glaucoma surgery and corneal transplantation. The mean age of the participants in the healthy control group was 55.1\u0026thinsp;\u0026plusmn;\u0026thinsp;18.5 years.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\n\u003ch2\u003eData analysis\u003c/h2\u003e\n\u003cp\u003eRoutine testing of all patients included slit-lamp microscopy, fundus, and best-spectacle corrected visual acuity (BSCVA) examinations at the time of diagnosis. Visual acuity was measured using the standard Landolt optotype. The measured decimal acuity was converted to logarithm of the minimum angle of resolution (logMAR) units using a Visual Acuity Conversion Chart. We defined amblyopia as reduced visual acuity with BSCVA below 20/20 without pathological causes such as cataracts and disorders in the macula and optic nerve.\u003csup\u003e17\u003c/sup\u003e A blinded observer (HK) graded the extent of corneal opacity and severity of bullous keratopathy based on the slit-lamp examination results according to a previously described system as follows:\u003csup\u003e18\u003c/sup\u003e corneal opacity grade; 0, clear or trace haze; grade 1, mild opacity; grade 2, moderately dense opacity partially obscuring the details of the iris; and grade 3, severely dense opacity obscuring the details of the intraocular structures. The severity of bullous keratopathy was defined as follows: stage 1, slight stromal oedema or increased corneal thickness due to reduction in corneal endothelial cells; stage 2, stromal oedema with DM folds; stage 3, stromal oedema and DM folds with apparent epithelial bullae; stage 4, stromal scarring and corneal neovascularization.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\n\u003ch2\u003eAnterior segment optical coherence tomography\u003c/h2\u003e\n\u003cp\u003eAS-OCT was used to evaluate the corneal structure in eyes with forceps corneal injury as reported previously.\u003csup\u003e14\u0026ndash;16\u003c/sup\u003e In brief, the CASIA system (SS-1000, Tomey, Nagoya, Japan) corrected distortions in the AS-OCT images based on the refractive index of the anterior surface. Two corneal specialists (HK and TY) carefully checked all AS-OCT images to ensure that the surface digitalization recognized by the automated inbuilt software was correct. The anterior and posterior corneal surfaces were reconstructed as a three-dimensional model from the corneal height data. The anterior, posterior, and total corneal aberrations at the diameters of 4mm and 6mm were calculated separately with the installed ray tracing software, version 5.1. The refractive indices of the cornea and aqueous humor were set to 1.376 and 1.336, respectively. The wavefront aberration was expanded with normalized Zernike polynomials up to the 8th order. HOA was defined as the root mean square (RMS) of the 3rd - to 8th -order Zernike coefficients as follows.[\u003cspan class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/p\u003e\n\u003cp\u003e\u003cimg src=\"data:image/png;base64,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\" alt=\"\" /\u003e\u003c/p\u003e\n\u003cp\u003eSpherical aberration (SA) was defined as the RMS of Z\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e0\u003c/sup\u003e (spherical aberration) and Z\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e0\u003c/sup\u003e(secondary spherical aberration). Coma aberration was defined as the RMS of Z\u003csub\u003e3\u003c/sub\u003e\u0026thinsp;\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and Z\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e1\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003e\u003cimg src=\"data:image/png;base64,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\" alt=\"\" /\u003e\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\n\u003ch2\u003eClassification of corneal shapes into five topographic patterns\u003c/h2\u003e\n\u003cp\u003eTopographic patterns were categorised into five types, i.e., regular astigmatism, asymmetric, protrusion, flattening, and posterior irregular with minimal anterior irregularity, as previously reported.\u003csup\u003e14\u0026ndash;16\u003c/sup\u003e Briefly, the AS-OCT images of corneas with forceps corneal injury showed a high degree of irregular astigmatism on the anterior and posterior surfaces. The regular astigmatism pattern was defined as regular astigmatism with an astigmatism power of \u0026ge;\u0026thinsp;3 diopter. The asymmetric pattern was defined as a mirror-image with blue and red asymmetric color on the topographic map of the anterior surface, half with a keratometric value of \u0026ge;\u0026thinsp;45 diopters and the other half with a keratometric value of \u0026le;\u0026thinsp;40 diopters. The protrusion pattern was defined as a centrally steep zone with a keratometric value of \u0026ge;\u0026thinsp;50 diopters on the anterior surface. The flattening pattern was defined as a flattened cornea with a keratometric value of \u0026le;\u0026thinsp;35 diopters on the anterior surface. The posterior irregular pattern with minimal anterior surface changes was considered when there were minimal changes in the anterior surface.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\n\u003ch2\u003eDescemet stripping automated endothelial keratoplasty\u003c/h2\u003e\n\u003cp\u003eAmong 23 eyes, 11 patients (11 eyes) underwent DSAEK. DSAEK was performed using double-glide technique. Briefly, after sub-Tenon anesthesia with injection of 2% lidocaine, a 4.5-mm temporal corneoscleral incision was made. Descemet stripping was performed with a reverse-bent Sinsky hook (Asico, Westmont, IL, USA). The recipient\u0026rsquo;s endothelium and Descemet\u0026rsquo;s membrane were carefully removed using forceps. Pre-cut donor grafts were trephinated and the endothelial surface of the donor lenticle was coated with a small amount of viscoelastic material. Donor tissue was gently inserted into the anterior chamber using a Busin glide (Asico) and Shimazaki forceps (Inami, Tokyo, Japan). Air was carefully injected into the anterior chamber to unfold the graft. At 10 min after air injection, half of the air was replaced by balanced salt solution (Alcon, Fort Worth, TX, USA). At the end of the surgery, 2mg subconjunctival betamethasone was administered. Corneal HOAs were evaluated 3 months after DSAEK.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n\u003ch2\u003eStatistical analysis\u003c/h2\u003e\n\u003cp\u003eThe data were analysed using the Prism software (ver. 6.04 for Windows; GraphPad Software, Inc., San Diego, CA, USA). The D\u0026rsquo;Agostino and Pearson omnibus normality test was used to assess whether the data showed a normal distribution. To compare the differences in HOAs between healthy subjects and patients with forceps corneal injury, the Mann-Whitney test was used. Spearman\u0026rsquo;s correlations were performed to determine the association between logMAR and each parameter including coma aberrations and HOAs within 4-mm and 6mm diameters, opacity grade, bullous stage, and CCT. To comparison between before and after DSAEK for corneal higher-order aberrations, Wilcoxon singed rank tests were used. All tests were 2-tailed and a \u003cem\u003eP\u003c/em\u003e value less than 0.05 was considered to indicate statistical significance.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003ePatient demographics\u003c/h2\u003e \u003cp\u003ePatient demographics are shown in Supplementary table 1. Of 23 eyes with forceps corneal injuries, 22 (95.7%) patients had amblyopia. The direction of DM break on slit photographs was horizontal (1\u0026ndash;30\u0026deg;, 151\u0026ndash;180\u0026deg;) in six eyes (26.1%), oblique (31\u0026ndash;60\u0026deg;, 121\u0026ndash;150\u0026deg;) in 12 eyes (52.2%), and vertical (61\u0026ndash;120\u0026deg;) in five eyes (21.7%). The direction of DM breaks was identical to that of the corneal astigmatism axis of the steep meridian in 14 of 23 eyes (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, 60.9%), whereas the direction of DM break was not associated with that of the corneal astigmatism axis of the steep meridian in the nine other eyes because of severe corneal deformations, such as asymmetric changes or protrusion.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eHigher-order aberrations in forceps corneal injuries\u003c/h2\u003e \u003cp\u003eCompared with the healthy control eyes, all HOA parameters, including HOAs, SA, and coma aberrations (total / anterior / posterior, 4mm / 6mm) were significantly higher in eyes with forceps corneal injury (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Total HOAs were larger than those of anterior surface in forceps corneal injury.\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\u003eCorneal Higher-order Aberrations in Bullous Keratopathy due to Forceps Injuries\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=\"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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eForceps Injuries\u003c/p\u003e \u003cp\u003e(23 eyes)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHealthy controls\u003c/p\u003e \u003cp\u003e(18 eyes)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHOA 4mm\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\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 \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.05 (0.76, 1.98)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.10 (0.08, 0.11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.92 (0.81, 1.69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.10 (0.09, 0.11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.50 (0.45, 0.77)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.02 (0.02, 0.02)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHOA (6mm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.79 (1.48, 2.83)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.19 (0.16, 0.21)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.03 (1.52, 2.82)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.19 (0.17, 0.22)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.87 (0.73, 1.06)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.06 (0.05, 0.07)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSA (4mm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.72 (0.43, 1.03)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.07 (0.05, 0.08)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.61 (0.40, 0.92)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.08 (0.06, 0.09)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.34 (0.20, 0.45)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.02 (0.01, 0.02)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSA (6mm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.00 (0.75, 1.51)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.13 (0.11, 0.15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.99 (0.77, 1.43)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.14 (0.12, 0.16)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.42 (0.35, 0.57)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.05 (0.05, 0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eComa (4mm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.83 (0.58, 1.69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.06 (0.05, 0.07)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.72 (0.53, 1.48)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.06 (0.05, 0.07)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.41 (0.30, 0.62)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.01 (0.01, 0.01)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eComa (6mm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.35 (1.17, 2.57)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.12 (0.10, 0.16)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.72 (1.31, 2.62)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.13 (0.11, 0.18)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.72(0.55, 0.96)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.02(0.02, 0.03)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003emedian (IQR)\u003c/p\u003e \u003cp\u003eHOA\u0026thinsp;=\u0026thinsp;higher order aberration; IQR\u0026thinsp;=\u0026thinsp;interquartile range; SA\u0026thinsp;=\u0026thinsp;spherical aberration\u003c/p\u003e \u003cp\u003e*Mann-Whitney U test\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eCorrelations among visual acuities, coma aberration and opacity grade\u003c/h2\u003e \u003cp\u003eLogMAR visual acuity was significantly positively correlated with coma aberrations in the 4-mm zone of the anterior surface, and 6-mm zones of the total cornea and anterior surface (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, r\u003csub\u003es\u003c/sub\u003e= 0.454, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.03; \u003cem\u003er\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e = 0.482, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.02; \u003cem\u003er\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e = 0.504, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.02, respectively). LogMAR visual acuity was positively correlated with the opacity grade and severity of the bullous stage (\u003cem\u003er\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e = 0.700, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0003; \u003cem\u003er\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e = 0.675, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0006, respectively), not with the CCT (r\u003csub\u003es\u003c/sub\u003e = 0.175, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.435).\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\u003eCorrelation between visual acuity, coma aberration, HOA, opacity grade, bullous stage, and CCT.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4 mm Zone\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6 mm Zone\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\u003eComa Aberration\u003c/b\u003e\u003c/p\u003e \u003cp\u003eTotal cornea\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.28 (0.21)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.482 (0.02)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior surface\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e0.454 (0.03)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.504 (0.02)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior surface\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-0.166 (0.46)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-0.018 (0.94)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHOA\u003c/b\u003e\u003c/p\u003e \u003cp\u003eTotal cornea\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.321 (0.14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.383 (0.071)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior surface\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.374 (0.08)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.471 (0.02)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior surface\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-0.014 (0.95)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.056 (0.80)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOpacity grade\u003c/b\u003e\u003csup\u003e\u003cem\u003ea\u003c/em\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e\u003cb\u003e0.700 (\u0026lt;\u0026thinsp;0.001)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBullous stage\u003c/b\u003e\u003csup\u003e\u003cem\u003eb\u003c/em\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e\u003cb\u003e0.675 (\u0026lt;\u0026thinsp;0.001)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCCT\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e0.175 (0.43)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eHOA\u0026thinsp;=\u0026thinsp;higher order aberration; IQR\u0026thinsp;=\u0026thinsp;interquartile range; SA\u0026thinsp;=\u0026thinsp;spherical aberration.\u003c/p\u003e \u003cp\u003e\u003csup\u003e\u003cem\u003ea\u003c/em\u003e\u003c/sup\u003ecorneal opacity grade; 0, clear or trace haze; grade 1, mild opacity; grade 2, moderately dense opacity partially obscuring the details of the iris; and grade 3, severely dense opacity obscuring the details of the intraocular structures.\u003c/p\u003e \u003cp\u003e\u003csup\u003e\u003cem\u003eb\u003c/em\u003e\u003c/sup\u003eThe severity of bullous keratopathy was defined as follows: stage 1, slight stromal edema or increased corneal thickness due to reduction in corneal endothelial cells; stage 2, stromal edema with DM folds; stage 3, stromal edema and DM folds with apparent epithelial bullae; stage 4, stromal scarring and corneal neovascularization.\u003c/p\u003e \u003cp\u003eData are expressed as Spearman's correlation coefficient \u003cem\u003er\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e (\u003cem\u003eP\u003c/em\u003e).\u003c/p\u003e \u003cp\u003eBold numbers indicate \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eCorneal topographical map patterns\u003c/h2\u003e \u003cp\u003eRepresentative cases are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. Protrusion and regular astigmatism patterns were identified as the most common alterations in the topographic maps (both, 6 eyes, 26.1%), followed by asymmetric pattern (5 eyes, 21.7%), flattening pattern (4 eyes, 17.4%), and posterior irregular pattern with minimal anterior surface changes (2 eyes, 8.7%).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eCorneal Higher-order Aberrations Before and After DSAEK\u003c/h2\u003e \u003cp\u003eAfter DSAEK, logMAR was improved from 1.52 (0.61 to1.70) (median [IQR]) to 0.52 (0.40 to 0.76) (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01, Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Corneal HOAs was significantly improved after DSAEK (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Although there were no statistically significant correlations presumably due to the small number of subjects, logMAR after DSAEK was weakly correlated with corneal HOA (6mm, \u003cem\u003er\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e= 0.59, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.06).\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\u003eCorneal Higher-order Aberrations Before and After DSAEK in Eyes with Bullous Keratopathy due to Forceps Injuries\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=\"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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eBefore DSAEK (11 eyes)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePost DSAEK\u003c/p\u003e \u003cp\u003e(11 eyes)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003csup\u003e*\u003c/sup\u003e\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\u003eBSCVA (logMAR)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.52 (0.61 to1.70)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.52 (0.40 to 0.76)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.01\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHOA 4mm\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.01 (0.93, 1.32)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.79 (0.61, 0.87)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.02\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.91 (0.84, 1.09)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.62 (0.58, 0.81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.02\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.49 (0.45, 0.60)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.31 (0.23, 0.43)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.08\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHOA (6mm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.63 (1.48, 2.09)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.43 (1.19, 1.96)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.70\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.00 (1.62, 2.19)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.60 (1.30, 2.03)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.20\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.77 (0.59, 0.85)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.70 (0.66, 0.99)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.32\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSA (4mm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.72 (0.50, 0.92)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.49 (0.32, 0.52)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.04\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.61 (0.58, 0.81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.41 (0.27, 0.42)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.01\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.39 (0.22, 0.45)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.22 (0.17, 0.28)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.16\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSA (6mm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.35 (1.27, 1.53)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.72 (0.64, 0.90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.55\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.98 (0.80, 1.24)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.66 (0.56, 0.78)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.01\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.39 (0.35, 0.51)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.44 (0.39, 0.52)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.35\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eComa (4mm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.77 (0.61, 0.91)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.63 (0.47, 0.69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.04\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.70 (0.54, 0.90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.56 (0.46, 0.68)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.11\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.36 (0.28, 0.47)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.22 (0.16, 0.30)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.10\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eComa (6mm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.35 (1.27, 1.53)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.24 (0.99, 1.74)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.77\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.72 (1.35, 1.92)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.49 (1.09, 1.92)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.47\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.63 (0.40, 0.73)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.55 (0.47, 0.60)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.30\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003emedian (IQR)\u003c/p\u003e \u003cp\u003eBSCVA\u0026thinsp;=\u0026thinsp;best-spectacle corrected visual acuity; HOA\u0026thinsp;=\u0026thinsp;higher order aberration; IQR\u0026thinsp;=\u0026thinsp;interquartile range; logMAR\u0026thinsp;=\u0026thinsp;logarithm of minimal angle resolution;\u003c/p\u003e \u003cp\u003eSA\u0026thinsp;=\u0026thinsp;spherical aberration.\u003c/p\u003e \u003cp\u003e*Wilcoxon rank sum test\u003c/p\u003e \u003cp\u003eBold numbers indicate \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eForceps corneal injury causes vision loss later in life and pain due to epithelial bulla formation associated with bullous keratopathy. As it is a rare disease, accounting for only 1\u0026ndash;2% of bullous keratopathy cases,\u003csup\u003e4\u003c/sup\u003e the clinical subtypes and degrees of astigmatism in eyes with forceps corneal injury remains poorly understood. The current study showed increased corneal HOAs, SAs and coma aberrations in eyes with bullous keratopathy due to forceps corneal injury. This study also showed that coma aberrations were associated with decreased visual acuity.\u003c/p\u003e\u003cp\u003eTo our knowledge, this was the largest case series to have quantified corneal aberrations and clinical data in eyes with forceps injuries. Owing to the small number of cases, previous studies have included samples of only one to 12 patients.\u003csup\u003e1\u0026ndash;3,6\u0026minus;8,19\u0026minus;26\u003c/sup\u003e Therefore, it has been difficult to accurately characterise clinical features such as the degree of regular and irregular astigmatism, incidence of amblyopia, corneal structure and optical properties. For example, since Lloyd reported six forceps corneal injuries in which the left eye was the affected eye in all cases,\u003csup\u003e27\u003c/sup\u003e it was believed that the left eye is often traumatised during the process of passing through the birth canal; \u003csup\u003e27\u003c/sup\u003e however, in this study, the injured eye was more often the right (57.1%) than the left (42.9%). Forceps corneal injury causes amblyopia because of a high degree of corneal astigmatism.\u003csup\u003e7\u003c/sup\u003eIn this case series, 22 of 23 patient eyes had amblyopia. Furthermore, we found that the direction of DM breaks coincided with the steep meridian of the cornea in 14 of 23 eyes (60.9%) with apparent astigmatism axis with regular and flattening topographic patterns, whereas in eyes with asymmetric and protrusion patterns, there was no association with the astigmatism axis. Interestingly, the topographic elevation map of the anterior and posterior surface showed that the corneal posterior shift was located exactly in the area of the DM breaks (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e), suggesting that DM breaks directly cause astigmatism in the posterior surface.\u003c/p\u003e\u003cp\u003eWhen comparing the HOAs of the total cornea (4 mm) based on our previous studies on various corneal diseases (Supplementary Fig.\u0026nbsp;1)\u003csup\u003e14\u0026ndash;16,28\u003c/sup\u003e corneal HOAs differed among various corneal diseases with large intraindividual differences (large standard deviation). Notably, visual acuity was significantly correlated with corneal HOAs in all corneal diseases, except granular corneal dystrophy type 2, where HOAs were not increased.\u003csup\u003e15\u003c/sup\u003e In forceps corneal injuries, the mean HOA was much higher than that in other diseases. Moreover, it is noteworthy that the corneal HOAs of the posterior surface were significantly larger in eyes with forceps corneal injury, this is related to larger HOAs of the total cornea. Theoretically, in healthy eyes, where the posterior and anterior surfaces are parallel to each other, aberrations of the posterior surface tend to compensate for those of the anterior surface, resulting in fewer corneal HOAs in the total cornea. \u003csup\u003e29\u003c/sup\u003e The disruption of parallelism between the anterior and posterior surfaces in forceps corneal injuries may cause the lack of compensation, leading to increased total corneal HOAs.\u003c/p\u003e\u003cp\u003eMeasurement of corneal HOAs is clinically relevant because it is correlated with visual acuity. We believe that corneal HOAs can comprise a universal diagnostic biomarker for decision-making in corneal transplantation, and can be applied to various corneal diseases, including forceps corneal injury.\u003c/p\u003e\u003cp\u003eIn the current study, we found that both the posterior surface, where the DM scroll is located, and the anterior surface had large aberrations in eyes with forceps corneal injury (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). When considering surgical indications, DASEK is a standard surgical treatment for forceps corneal injury because of its several advantages over penetrating keratoplasty (PKP), including rapid visual recovery, biomechanical properties, and integrity. \u003csup\u003e30\u0026ndash;32\u003c/sup\u003e However, in DSAEK, large amounts of HOAs on the anterior surface can remain after surgery and adversely effect on visual acuity. In the current case series, 18 patients underwent corneal transplantation (PKP in 4 eyes and DSAEK in 14 eyes). Although logMAR visual acuity significantly improved from 1.70 (IQR, 0.7 to 1.85) to 1.00 (IQR, 0.52 to 1.70) after corneal transplantation, the improvement in visual acuity was limited especially in patients with large HOAs in the anterior surface. The residual HOAs after DSAEK were influenced by the preoperative HOAs due to stromal deformation in forceps corneal injury. Thus, we need to evaluate corneal HOAs, when deciding whether to perform PKP or DSAEK in eyes with forceps corneal injury.\u003c/p\u003e\u003cp\u003eThis study had several limitations. First, the patient age at onset of bullous keratopathy due to forceps corneal injury could have caused bias. Age has been reported to affect visual function, refraction, and astigmatism.\u003csup\u003e33\u003c/sup\u003e However, age-related HOA changes are minor, compare with the increase in corneal HOAs in eyes with forceps corneal injury. Therefore, we believe that the age-related bias was minimal. Second, there might be some differences in the refractive indices between normal corneas and bullous keratopathy, which may have influenced our estimated HOAs. Theoretically, corneal oedema can affect refractive index and errors in refractive power of the cornea by less than 5%,\u003csup\u003e34,35\u003c/sup\u003e minimally influencing the results of the current study. Third, 22 eyes (95.7%) in current study had amblyopia. However, a correlation between visual acuity and corneal aberrations was observed, despite the presence of amblyopia.\u003c/p\u003e\u003cp\u003eIn conclusion, Descemet\u0026rsquo;s scrolls in eyes with forceps injuries induce morphometric changes in the anterior and posterior surfaces, leading to increased corneal HOAs, SAs and coma of the total cornea and anterior and posterior surfaces. We also classified irregular astigmatism patterns into five types, based on the corneal topographic map. The most common patterns are protrusion and regular astigmatism. Furthermore, increases in coma were significantly correlated with visual acuity, indicating that coma may be a biomarker for assessing visual function in eyes with forceps corneal injuries.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eAll authors certify that they have no involvement with any entity or organization with any financial interest in the subject matter or materials discussed in the manuscript.\u003c/p\u003e\n\u003cp\u003eFinancial support: None\u003c/p\u003e\n\u003cp\u003eMeeting presentation: We presented this study in ARVO2022.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgment\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eH.K. had full access to all the data in the present study and takes responsibility for its integrity and accuracy of the data analyses. H.K. and T.Y. designed the study. H.K., Y.Y.Y., T.Y., S.N., T.M., and J.S. acquired and interpreted data. H.K., T.Y., and J.S. drafted the manuscript. All authors reviewed and approved the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eNoyes HD. Traumatic Keratitis caused by forceps delivery of an infant. Trans Am Ophthalmol Soc \u003cb\u003e7\u003c/b\u003e,454\u0026ndash;455 (1895).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAngell LK, Berson FG. Visual Prognosis in Patients With Ruptures in Descemet's Membrane due to Forceps Injuries. Arch Ophthalmol \u003cb\u003e99\u003c/b\u003e, 2137\u0026ndash;2139 (1981).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHonig MA, Barraquer J, Perry HD, Riquelme JL, Green WR. Forceps and vacuum injuries to the cornea histopathologic features of twelve cases and review of the literature. Cornea \u003cb\u003e15\u003c/b\u003e,463\u0026ndash;472 (1995).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eShimazaki J, Amano S, Uno T, Maeda N, Yokoi N; the Japan Bullous Keratopathy Study Group. National survey on bullous keratopathy in Japan. Cornea \u003cb\u003e26\u003c/b\u003e,274\u0026ndash;278 (2007).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYazu H, Yamaguchi T, Aketa N, Higa K, Suzuki T, Yagi-Yaguchi Y, et al. Preoperative Aqueous Cytokine Levels are Associated With Endothelial Cell Loss After Descemet's Stripping Automated Endothelial Keratoplasty. Invest Ophthalmol Vis Sci \u003cb\u003e59\u003c/b\u003e, 612\u0026ndash;620 (2018).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKobayashi A, Yokogawa H, Mori N, Sugiyama K. Case series and techniques of Descemet's Stripping Automated Endothelial Keratoplasty for severe bullous keratopathy after birth injury. BMC Ophthalmol \u003cb\u003e15\u003c/b\u003e, 92:1\u0026ndash;7 (2015).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eScorcia V, Pietropaolo R, Carnevali A, De Luca V, Lucisano A, Busin M. Results of descemet stripping automated endothelial keratoplasty for the treatment of late corneal decompensation secondary to obstetrical forceps trauma. Cornea \u003cb\u003e35\u003c/b\u003e, 305\u0026ndash;307 (2016).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHayashi T, Hirayama Y, Yamada N, Shimazaki-Den S, Shimazaki J. Descemet stripping automated endothelial keratoplasty for bullous keratopathy with an irregular posterior surface. Cornea \u003cb\u003e32\u003c/b\u003e,1183\u0026ndash;1188 (2013).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRadhakrishnan S, Yarovoy D. 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Variation of corneal refractive index with hydration. Phys Med Biol \u003cb\u003e49\u003c/b\u003e, 859\u0026ndash;868 (2004).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMeek KM, S Dennis, Khan S. Changes in the refractive index of the stroma and its extrafibrillar matrix when the cornea swells. Biophys J \u003cb\u003e85\u003c/b\u003e, 2205\u0026ndash;2012 (2003).\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":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Forceps corneal injury, higher-order aberrations, corneal astigmatism, Descemet’s membrane rupture, corneal endothelial decompensation","lastPublishedDoi":"10.21203/rs.3.rs-2425903/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-2425903/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eForceps corneal injuries during infant delivery cause Descemet membrane (DM) breaks, that cause corneal astigmatism and corneal endothelial decompensation. The aim of this study is to characterise corneal higher-order aberrations (HOAs) and corneal topographic patterns in corneal endothelial decompensation due to obstetric forceps injury. This retrospective study included 23 eyes of 21 patients (54.0\u0026thinsp;\u0026plusmn;\u0026thinsp;9.0 years old) with forceps corneal injury, and 18 healthy controls. HOAs and coma aberrations were significantly larger in forceps injury (1.05 [0.76 to 1.98] \u0026micro;m, and 0.83 [0.58 to 1.69], respectively) than in healthy controls (0.10 [0.08 to 0.11], and 0.06 [0.05 to 0.07], respectively, both \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.0001). Patient visual acuity was positively correlated with coma aberration (\u003cem\u003er\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e = 0.482, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.023). The most common topographic patterns were those of protrusion and regular astigmatism (both, six eyes, 26.1%), followed by asymmetric (5 eyes, 21.7%), flattening (4 eyes, 17.4%). These results indicate that increased corneal HOAs are associated with decreased visual acuity in corneal endothelial decompensation with DM breaks and corneal topography exhibits various patterns in forceps injury.\u003c/p\u003e","manuscriptTitle":"Corneal Higher-order Aberrations in Corneal Endothelial Decompensation Secondary to Obstetric Forceps Injury","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-01-13 15:43:11","doi":"10.21203/rs.3.rs-2425903/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2023-02-20T07:48:25+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2023-02-19T06:28:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"79d20fff-87dd-4808-89ff-fbb0776a8cd2","date":"2023-02-15T02:40:57+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2023-01-25T07:34:59+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"1d567acf-6259-4946-a6a4-86e10e2e82d4","date":"2023-01-16T10:23:50+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2023-01-16T07:46:39+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2023-01-16T07:02:43+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2023-01-12T10:27:10+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2023-01-12T10:09:36+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2022-12-29T15:41:51+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"4b423d94-6cde-4fdb-a401-05724517c7fa","owner":[],"postedDate":"January 13th, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":18351190,"name":"Health sciences/Medical research"},{"id":18351191,"name":"Health sciences/Diseases/Eye diseases"}],"tags":[],"updatedAt":"2023-10-16T20:26:53+00:00","versionOfRecord":{"articleIdentity":"rs-2425903","link":"https://doi.org/10.1038/s41598-023-32683-5","journal":{"identity":"scientific-reports","isVorOnly":false,"title":"Scientific Reports"},"publishedOn":"2023-04-03 20:22:30","publishedOnDateReadable":"April 3rd, 2023"},"versionCreatedAt":"2023-01-13 15:43:11","video":"","vorDoi":"10.1038/s41598-023-32683-5","vorDoiUrl":"https://doi.org/10.1038/s41598-023-32683-5","workflowStages":[]},"version":"v1","identity":"rs-2425903","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-2425903","identity":"rs-2425903","version":["v1"]},"buildId":"GqpaHPwrfC8PjnIFayRh5","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}