Effects of Tilt and Decentration of Visian Implantable Collamer Lens (ICL V4c) on Visual Quality: An Observational Study

Effects of Tilt and Decentration of Visian Implantable Collamer Lens (ICL V4c) on Visual Quality: An Observational Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Effects of Tilt and Decentration of Visian Implantable Collamer Lens (ICL V4c) on Visual Quality: An Observational Study Lingling Niu, Zhe Zhang, Huamao Miao, Jing Zhao, Meiyan Li, Ji C He, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-1287972/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 8 You are reading this latest preprint version Abstract Objectives To investigate the tilt and decentration effects of the Visian Implantable Collamer Lens (ICL V4c) on visual quality after implantation. Methods A total of 135 eyes from 69 patients who underwent ICL V4c implantation were included in this study. Evaluation of spherical equivalent, uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and aberrations were performed 6-months postoperatively. The anterior segment parameters were collected using CASIA2 anterior segment-optical coherence tomography, and tilt and decentration of the ICL V4c were analyzed using MATLAB software. All patients received questionnaires to investigate the visual quality postoperatively. Results The safety and effectiveness were 1.18 ± 0.17 and 1.11 ± 0.18, respectively. No significant changes were observed regarding higher-order and spherical aberrations after the operation; however, coma and trefoil significantly increased compared to preoperative values. The average decentration was 0.21 ± 0.12 mm. The average tilt was 2.54 ± 1.00°. Horizontal, vertical, and total values of tilt and decentration were not significantly associated with postoperative CDVA, UDVA, and aberrations. The most common visual symptom was halo, and 97.04% of patients had a satisfaction score ≥ 8. The total or vertical tilt was significantly positively correlated with the frequency, severity, and bothersome scores from the questionnaires. Conclusions ICL V4c implantation can obtain high visual quality and patient satisfaction. Although the degree of tilt and decentration after ICL V4c implantation was small, a positive effect on subjective visual quality was observed. Implantable Collamer Lens myopia decentration tilt visual quality Figures Figure 1 Figure 2 Figure 3 Introduction In 2005, the United States Food and Drug Administration approved the use of the Implantable Collamer Lens (ICL, STAAR Surgical, Nidau, Switzerland), which has since demonstrated its safety and efficacy as a treatment method for high myopia[ 1 – 3 ]. The ICL is reversible and maintains the central cornea integrity and promotes early recovery of visual acuity[ 4 , 5 ]. The CentraFLOW technology in the Visian Implantable Collamer Lens (ICL V4c) contains a 360-µm central hole that promotes aqueous humor circulation, which reduces the incidence of cataract formation, decreases reduction of corneal endothelial cell and eliminates the need to perform neodymium:YAG (Nd: YAG) iridotomy before ICL implantation[ 6 – 8 ]. Studies have shown that ICL V4c implantation produces better visual quality compared with laser-assisted in situ keratomileusis and small incision lenticule extraction; however, post-ICL implantation complications including high-order aberrations and coma aberrations increased still occur, as well as symptoms, including halo and glare[ 9 – 13 ]. Tilt and decentration of the intraocular lens (IOL) can cause higher-order aberrations, which may lead to deterioration of visual function[ 14 , 15 ]. Therefore, ICL tilt and decentration effects on postoperative visual quality warrant investigation. The hole in the ICL provides a reference that allows observation of the position of the lens to evaluate the presence of tilt or decentration. The ICL hole is not usually located in the central pupil[ 16 ]; however, previous studies regarding the effect of ICL V4c decentration on visual acuity were in-vitro studies, and in-vivo experiments are lacking[ 17 , 18 ]. The new generation anterior segment optical coherence tomography (AS-OCT) possesses a 1310-nm laser wavelength (CASIA2, Tomey, Japan), and has the advantages of high axial and transverse resolutions of 10 µm and 30 µm, respectively, high repeatability, and is non-mydriatic[ 19 ]. Furthermore, it can clearly display the anterior and posterior surfaces of the cornea, ICL, and crystalline lens. Additionally, AS-OCT automatically measures the tilt and decentration of the lens as a reference to the corneal topographic axis. This is the first study to aim to measure and analyze the post-implantation tilt and decentration of the ICL V4c and evaluate the effects on patients’ visual quality. Methods Subjects All patients were fully informed of the details and potential risks of the procedure, and written informed consent was obtained from all patients. The Ethics Committee of the Fudan University EENT Hospital Review Board approved the study protocol (No. 2016038), and the study adhered to the tenets of the Declaration of Helsinki. In this observational study, we recruited individuals who underwent ICL V4c implantation at our hospital. The inclusion criteria were: (1) age 20–42 years; (2) stable refractive error (≤ 0.50 D change per year in refractive error in the past 2 years); (3) minimum anterior chamber depth (ACD) of 2.8 mm and a minimum endothelial cell density (ECD) of 2000 cells/mm 2 ; (4) no contact lens use for at least 2 weeks. The exclusion criteria were: (1) presence of comorbid eye disorders; (2) suspicion of keratectasia; and (3) presence of comorbid systemic diseases. Visian Implantable Collamer Lens The power calculation of the ICL V4c (STAAR Surgical, Nidau, Switzerland) was performed using a modified vertex formula based on the preoperative refractive parameters, according to the manufacturer’s instructions. The size of the implanted ICL V4c was determined from the white-to-white, horizontal corneal diameter, and ACD. Surgical procedure An experienced surgeon (XZ) performed all ICL V4c implantations, as described previously[ 20 ]. Briefly, pupils were dilated preoperatively. A mark was made to show the horizontal axis on the limbus to allow the use of a Toric ICL. Using an injector cartridge, the ICL was implanted via a 3.0-mm temporal corneal incision. Then a moderate viscoelastic surgical agent (1% sodium hyaluronate) was injected into the anterior chamber and the ICL V4c lens was placed and positioned in the posterior chamber. The viscoelastic surgical agent was washed away entirely using a balanced salt solution, and a miotic agent was instilled. Postoperative medications included antibiotic, non-steroidal anti-inflammatory, steroidal, and artificial tears eye drops. Follow-up examination All patients underwent preoperative and postoperative ocular examinations. The following main parameters were evaluated: uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), subjective manifest refraction, intraocular pressure (IOP, Canon, Japan), corneal topography and vault (Pentacam HR, Oculus Optikgeräte GmbH, Wetzlar, Germany), wavefront aberration analysis (WASCA Wavefront Analyzer, Carl Zeiss Meditec, Germany), ECD (SP-95 2000P, Topcon Corporation, Japan), and ultrasound biomicroscopy (Quantel Medical, French). Patients were followed-up after 6 months postoperatively. The wavefront aberration is analyzed by Zernike polynomial and presented according to the Optic Society of America standard. AS-OCT measurement The ocular anterior segment parameters were measured using AS-OCT (CASIA2; TOMEY, Nagoya, Japan). The chins and foreheads of all patients were fixed and gazed at a fixation target to fully expose the corneal limbus. A total of 128 anterior segment tomographic images of the entire circumference was obtained in only 2.4 s, and the measurements were repeated three times by the same examiner. Each OCT image clearly presents the anterior and posterior surfaces of the cornea, lens, and ICL. Sixteen images from 0° to 180° with different directions (0, 11, 23, 34, 45, 56, 68, 79, 90, 101, 113, 124, 135, 146, 158, and 169 degrees) were selected for each eye for analysis; the 0° and 90° images represented the horizontal and vertical orientation, respectively. Additionally, the maximum value of tilt or decentration within the 16 images represented the total tilt or total decentration value. Tilt and decentration values The AS-OCT images were analyzed using MATLAB software (R2018a, The MathWorks, Inc., Natick, MA, USA), which created four simulation lines from anterior to posterior; these lines were manually adjusted to coincide with the anterior and posterior corneal surfaces and ICL surfaces. Individual location values of the ICL were converted into coordinates (x and y). The software automatically calculates the (x, y) displacement of the anterior corneal surface apex and left and right endpoints of the central ICL hole. The corneal topography axis was defined as the line connecting the fixation point of the machine to the corneal apex. The ICL axis was defined as the line connecting the centers of the circles where the anterior and posterior surfaces of the ICL were located (Fig. 1 ). Decentration value was defined as the x-axis displacement between the center of the ICL hole and the corneal topography axis, while the tilt value was the angle between the ICL axis and the corneal topography axis. The values on the coordinate axes were expressed in pixels, which were converted to standard descriptive statistics (Unit: mm). Both the decentration and tilt values were analyzed as absolute values. All image analyses were performed independently by two examiners and the consistency of the results were evaluated. The intraclass correlation coefficient, Bland-Altman analysis plot, and cross-classification showed consistent results for the two analyses (p < 0.05). All results were averaged from the two analyses. Questionnaire design All patients completed a questionnaire to report their subjective quality of vision during the follow-up at 6 months postoperatively (Fig. 2 A). The Quality of Vision (QoV) Questionnaire by McAlinden consists of a Rasch-tested, linear-scaled, 30-item instrument that includes three scales and provides a QoV score in terms of symptom frequency, severity, and bothersome[ 21 ]. It is suitable for measuring QoV in patients with refractive correction. The 10 symptoms included glare, haloes, starbursts, hazy vision, blurred vision, distortion, double vision, fluctuation, focusing difficulties, and depth perception. Patients were asked regarding their overall satisfaction with the surgery, with 0 being dissatisfied and 10 being a perfect score of satisfied. Statistical analyses Statistical analyses were performed using R software Version 3.4.3 ( http://www.R-project.org ). Continuous and categorical variables were expressed as means ± standard deviations and frequencies (percentages), respectively. A paired t-test was used to analyze the difference between postoperative horizontal and vertical tilt or decentration. The generalized estimating equation model was used to analyze the correlation between tilt or decentration and aberration or visual quality score, which was adjusted for age, eye, preoperative refraction, and preoperative scotopic pupil at treatment. Statistical significance was set at p < 0.05. Results Subjects’ biometrics A total of 135 eyes from 69 patients (56 women and 13 men) with an average age of 28.88 ± 5.46 years (20–40 years) was enrolled in this observational clinical study; among them, 89 eyes were implanted with a Toric ICL. The preoperative mean CDVA was 1.01 ± 0.17 (0.5 to 1.2) and the mean spherical equivalent (SE) was − 10.16 ± 2.99 diopters (D) (-4.0 to -18.50 D). At the 6-month follow-up, the mean postoperative UDVA and CDVA were 1.12 ± 0.23 (0.5 to 1.5) and 1.18 ± 0.19 (0.6 to 1.5) respectively; the mean postoperative SE was − 0.13 ± 0.44 (-2.25, 0.75). The efficacy index (postoperative UDVA/preoperative CDVA) was 1.11 ± 0.18 and the safety index (postoperative CDVA/preoperative CDVA) was 1.18 ± 0.17. All 135 eyes achieved a postoperative SE within ± 1.0 D of the attempted SE. No significant changes in IOP were observed between the preoperative (15.25 ± 2.60 mmHg) and 6 months postoperative (14.87 ± 2.82 mmHg) values (p = 0.61). The number of ECD decreased by 0.6% compared with the preoperative ECD (2577.71 ± 214.58 vs. 2568.66 ± 229.75, p = 0.61). The vault was 554.62 ± 227.83 µm (165–1360), and no clinical cataracts were observed. Additionally, 91.9% of patients had a scotopic pupil with a preoperative diameter > 5.8 mm. Tilt and decentration At 6 months postoperatively, the detail results of total, horizontal and vertical tilt and decentration of all ICLs were presented in Table 1 . Table 1 The tilt and decentration of ICL V4c postoperatively (N = 135 eyes) Characteristic Mean ± SD Range (Minimum, Maximum) Total tilt (°) 2.54 ± 1.00 0.35, 4.53 Horizontal tilt (°) 1.78 ± 1.06 0.05, 4.65 Vertical tilt (°) 1.22 ± 0.91 0, 3.85 Total decentration (mm) 0.21 ± 0.12 0.019, 0.520 Horizontal decentration (mm) 0.14 ± 0.10 0, 0.375 Vertical decentration (mm) 0.14 ± 0.10 0, 0.442 ICL V4c = Visian Implantable Collamer Lens;SD = standard deviation. The horizontal tilt was significantly greater than the vertical tilt (p = 0.000). Among them, 28.1% of the operated eyes were tilted within 2.0°, 91.85% within 4.0°, and the maximum did not exceed 5.0°. No significant difference was observed between the horizontal and vertical decentration (p = 0.730). The distribution of the decentration was 47.4% within 0.2 mm, 98.5% within 0.5 mm, and the maximum decentration value did not exceed 0.6 mm (Fig. 2 A). Aberration At the 6-month follow-up, both coma and trefoil were significantly increased, from 0.12 ± 0.09 and 0.09 ± 0.08 to 0.14 ± 0.09 (p = 0.003) and 0.16 ± 0.09 (p = 0.000), pre- and postoperatively respectively. In contrast no significant changes were observed in total higher-order and spherical aberrations after surgery (0.34 ± 0.88 and 0.06 ± 0.05 preoperatively vs. 0.28 ± 0.10 and 0.07 ± 0.05 postoperatively, respectively; p = 0.443 and 0.274). Quality of Vision questionnaire At the 6-month follow-up, the most frequent visual symptoms reported by the patients were halos (93.33%), glare (54.81%), blurred vision (41.48%), and fluctuation (33.33%), which were only reported in 8.15%, 1.48%, 1.38%, and 0% of the operated eyes, respectively, as more than mildly bothersome to the patient. The frequency, severity, and bothersome scores of the 10 different postoperative visual symptoms are shown in Fig. 2 B. The visual symptom frequency, severity, and bothersome scores were 33.87 ± 12.29 (0–59), 25.28 ± 11.29 (0–49), and 15.77 ± 13.31 (0–46), respectively. Relationship between tilt, decentration, and visual quality Horizontal, vertical, and total ICL tilt or decentration were not significantly correlated with postoperative CDVA, UDVA, higher-order aberration, coma, trefoil, and spherical aberration (p > 0.05). On the other hand, the total and horizontal tilt were positively correlated with frequency (p = 0.000, r = 0.414, and p = 0.003, r = 0.255, respectively), severity (p = 0.000, r = 0.367, and p = 0.001, r = 0.292, respectively), and bothersome (p = 0.000, r = 0.380, and p = 0.000, r = 0.421, respectively) scores of visual symptoms. No significant correlation was observed between vertical tilt, total decentration, horizontal decentration, vertical decentration, and visual symptom scores (Fig. 3 ). Discussion The clinical efficacy and long-term safety of ICL implantation for myopia correction have been widely recognized[ 1 – 5 ]. However, technological and material developments have led to higher standards of postoperative visual quality in both doctors and patients. Moreover, some patients complained of their visual disturbances despite having visual acuities of 1.0 or better and refractions close to plano after surgeries. Our study is the first to measure and analyze tilt and decentration after ICL V4c implantation and evaluate their effects on the visual quality of patients. The CentralFLOW technology in the ICL V4c contains a 360-µm central hole, which provides a reference to fix the center of the ICL and allows observation of ICL decentration relative to the corneal topographic axis. Our study collected images using the AS-OCT, and analyzed the decentration and tilt values of the ICL using MATLAB software. The average total decentration was 0.21 ± 0.12 mm and the 98.5% decentration was within 0.5 mm at 6 months postoperatively. Several clinical studies have reported that the average decentration of IOL post-cataract surgery is approximately 0.23–0.40 mm and the tilt is 3.03°–7.00°[ 22 – 24 ]. Compared with these values, our findings are relatively lower; this discrepancy may be attributed to the location of the ICL haptics on the ciliary sulcus, which allows more stability and less influence from the suspensory ligament and other structures[ 25 ]. A study of ICL that used the pupil center as the reference, reported that decentration of 48.9% and 93.6% of eyes were within 0.36 mm and 0.72 mm, respectively, and that of 93.6% eyes were within 0.72 mm after ICL implantation[ 26 ]. Notably, the selection criteria of the reference axis remain ununified. In corneal refractive surgery, significant decreases were observed in higher-order aberration and coma, and significant increase in contrast sensitivity when the corneal apex was used as the correction center rather than the center of the pupil[ 27 – 29 ]. Since it is affected by pupil shape, the pupil axis may not be the best reference to evaluate the tilt and decentration of an ICL[ 30 ]. The axis of corneal topography is a line connecting the fixed point of the machine and the first Purkinje image on the anterior surface of the cornea; while the apex of the cornea is a reflection point on the anterior surface of the cornea[ 31 ]. In this study, we used the second generation AS-OCT to measure the tilt and decentration of ICL, which is not affected by the pupil shape and diameter with high repeatability. A previous study reported that tilt and decentration of the IOL can induce image quality degradation in patients who developed postoperative coma, spherical aberration, and higher-order aberrations[ 14 , 15 ], especially with an aspheric IOL[ 32 , 33 ]. Some studies have measured the maximum decentration and tilt of the aspheric IOL, which ensured the comparable visual quality between aspheric and standard IOL. Holladay reported that the critical decentration and tilt values are 0.4 mm and 7°, respectively; visual function will be affected once values are beyond these ranges[ 32 ]. The aberration or astigmatism caused by the tilt or decentration of aspheric IOL may affect the image quality of the retina, which inhibits clear image formation of the peripheral part of the retina, leading to glare, halo or monocular diplopia. The spherical shape of the optical zone of the ICL causes the decentration and tilt to have little influence on the objective visual quality. Pérez-Vives[ 17 , 18 ] reported the results of an ICL decentration simulation test in vitro, and found that coma was directly correlated with the decentration value of the ICL and increased more with pupil diameter and higher refractive degree. Our study showed that tilt and decentration had no significant effect on postoperative aberrations, and had no significant correlation with postoperative UDVA and CDVA after adjusting for age, eye, preoperative refraction, and preoperative scotopic pupil, which is consistent with the results of Park[ 26 ]. Additionally, the effect of ICL decentration and tilt on postoperative visual acuity would be clinically insignificant. The reported visual symptoms of patients after ICL implantation in the order of most to least frequent were halo, glare, blurred vision, fluctuation, hazy vision, starbursts, focusing difficulties, double vision, depth perception, and distortion[ 13 ]. Similarly, Chen et al. found that patients with a small pupil diameter had a smaller halo radius after ICL implantation[ 34 ]. The largest optical area of ICL V4c was 5.8 mm. In our study, 91.9% of the eyes had dark pupil diameter larger than 5.8 mm; therefore, most patients occasionally experienced symptoms such as halo or glare. The total and horizontal tilt were positively correlated with the frequency, severity, and bothersome of visual symptoms scores. Eom et al. suggested that the halo is mainly due to the reflection of the inner wall of the central hole and posterior surface of ICL[ 12 ]. Eppig found that light through the central hole has no influence on the postoperative visual quality; however, the off-axis light will increase the intraocular reflection and scattering, which affects the postoperative visual quality[ 35 ]. Therefore, visual disturbances may be more evident with severe tilt. The limitations of this study were an observational study with short follow-up postoperative period and we will design further studies to observe the time-dependent changes of tilt and decentration results post-ICL implantation. And to overcome these limitations, both eyes were enrolled in this study, and we adjusted for eye laterality, patient age, and preoperative refraction during the statistical analysis to increase the accuracy and robustness of the results. In conclusion, ICL V4c implantation can obtain high visual quality and patient satisfaction. Although the degree of tilt and decentration after ICL V4c implantation was small, a positive effect on subjective visual quality was observed. List Of Abbreviations ICL, Implantable Collamer Lens; UDVA, Uncorrected distance visual acuity; CDVA, Corrected distance visual acuity; AS-OCT, anterior segment-optical coherence tomography ACD, Anterior chamber depth; IOP, Intraocular pressure; ECD, Endothelial cell density; SE, spherical equivalent; D, diopters; QoV, Quality of Vision. Declarations Ethics approval and Consent to participate The Ethics Committee of the Fudan University EENT Hospital Review Board approved the study protocol (No. 2016038), and the study adhered to the tenets of the Declaration of Helsinki. All methods were carried out in accordance with relevant guidelines and regulations. All patients were fully informed of the details and potential risks of the procedure, and written informed consent was obtained from all patients. Consent for publication Not applicable Acknowledgements The authors thank Dr. Jian Gao of Zhongshan Hospital for providing statistical consultations. We would also like to thank all the patients participating in the study. Data availability statement The data that support the findings of this study are available from EENT hospital of Fudan university but restrictions apply to the availability of these data, which were used under license for the current study, and so are not publicly available. Data are however available from the authors upon reasonable request and with permission of EENT hospital of Fudan university. Funding statement This work was supported by National Natural Science Foundation of China (Grant No. 81770955), Research Project Grant of Shanghai Municipal Health Commission (202040285), Project of Shanghai Science and Technology (Grant No.20410710100), Joint research project of new frontier technology in municipal hospitals (SHDC12018103), Clinical Research Plan of SHDC (SHDC2020CR1043B), Project of Shanghai Xuhui District Science and Technology (2020-015). The funding agencies had no role in study design, data collection and analysis, interpretation of data, or writing the manuscript. Competing interests statement The authors declare that there is no competing interest. Author contributions statement Literature screening and selection was performed by LN. XZ and PY participated in the design of the study. ZZ drafted the manuscript. 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Holladay JT, Piers PA, Koranyi G, van der Mooren M, Norrby NE: A new intraocular lens design to reduce spherical aberration of pseudophakic eyes . J Refract Surg 2002, 18 (6):683–691. Piers PA, Weeber HA, Artal P, Norrby S: Theoretical comparison of aberration-correcting customized and aspheric intraocular lenses . J Refract Surg 2007, 23 (4):374–384. Chen X, Han T, Zhao F, Miao H, Wang X, Zhou X: Evaluation of Disk Halo Size after Implantation of a Collamer Lens with a Central Hole (ICL V4c) . J Ophthalmol 2019, 2019 :7174913. Eppig T, Spira C, Tsintarakis T, El-Husseiny M, Cayless A, Muller M, Seitz B, Langenbucher A: Ghost-image analysis in phakic intraocular lenses with central hole as a potential cause of dysphotopsia . J Cataract Refract Surg 2015, 41 (11):2552–2559. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Major revision 15 Apr, 2022 Reviews received at journal 20 Mar, 2022 Reviewers agreed at journal 05 Mar, 2022 Reviewers invited by journal 04 Mar, 2022 Editor assigned by journal 04 Mar, 2022 Editor invited by journal 03 Mar, 2022 Submission checks completed at journal 01 Mar, 2022 First submitted to journal 23 Jan, 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board 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-1287972","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":87409787,"identity":"c2f3d7ea-3c92-4015-9640-b4e042bfd0a3","order_by":0,"name":"Lingling Niu","email":"","orcid":"","institution":"Fudan University Department of Ophthalmology","correspondingAuthor":false,"prefix":"","firstName":"Lingling","middleName":"","lastName":"Niu","suffix":""},{"id":87409788,"identity":"4441fb22-f34f-4eee-83d0-d9909ceabf20","order_by":1,"name":"Zhe Zhang","email":"","orcid":"","institution":"Fudan University Department of Ophthalmology","correspondingAuthor":false,"prefix":"","firstName":"Zhe","middleName":"","lastName":"Zhang","suffix":""},{"id":87409789,"identity":"7fd1df94-1d16-48c8-8af9-5da7fc030b12","order_by":2,"name":"Huamao Miao","email":"","orcid":"","institution":"Fudan University Department of Ophthalmology","correspondingAuthor":false,"prefix":"","firstName":"Huamao","middleName":"","lastName":"Miao","suffix":""},{"id":87409790,"identity":"481bb808-c607-4f22-8869-c13111b22eb5","order_by":3,"name":"Jing Zhao","email":"","orcid":"","institution":"Fudan University Department of Ophthalmology","correspondingAuthor":false,"prefix":"","firstName":"Jing","middleName":"","lastName":"Zhao","suffix":""},{"id":87409791,"identity":"74605872-9c42-43a4-8c60-31929f8aca08","order_by":4,"name":"Meiyan Li","email":"","orcid":"","institution":"Fudan University Department of Ophthalmology","correspondingAuthor":false,"prefix":"","firstName":"Meiyan","middleName":"","lastName":"Li","suffix":""},{"id":87409792,"identity":"cdcfcaf0-3fb8-4ab6-b6ca-a99df867cd82","order_by":5,"name":"Ji C He","email":"","orcid":"","institution":"New England College of Optometry, Boston, Massachusetts, USA.","correspondingAuthor":false,"prefix":"","firstName":"Ji","middleName":"C","lastName":"He","suffix":""},{"id":87409793,"identity":"6142efc3-67e8-4d09-ab07-dbd755b19d47","order_by":6,"name":"Peijun Yao","email":"","orcid":"","institution":"Fudan University Department of Ophthalmology","correspondingAuthor":false,"prefix":"","firstName":"Peijun","middleName":"","lastName":"Yao","suffix":""},{"id":87409794,"identity":"a4c26505-808e-43cd-862c-4abf94f693fb","order_by":7,"name":"Xingtao Zhou","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA80lEQVRIiWNgGAWjYDCCA0DM2AAkmCF8OTb29gOEtDA2wLUA1Rrz8ZxJIFIL1MrEeRIOBnh18B1vfv7w5w6bxA3HeQ+//lBjk94mwZDA8KNiG04tkmeOGTZInklLnNnMl2Zx4Fhabpt04wHGnjO3cWoxuJHD2GDYdjixn5nHzOAA2+HcNpkDCcyMbQS0JAK1tIG1/DucziaRYEBYy0GILcYPgIwEglpAfpnZ2JZmPLOZx4zhbF+aYRswkA/i8wswxB58/NlmI7vh/BnjDxXfbOTl29sPPvhRgVsLMmCTgLEOEKUeCJg/EKtyFIyCUTAKRhYAAHhnYH4bq984AAAAAElFTkSuQmCC","orcid":"","institution":"Fudan University Department of Ophthalmology","correspondingAuthor":true,"prefix":"","firstName":"Xingtao","middleName":"","lastName":"Zhou","suffix":""}],"badges":[],"createdAt":"2022-01-23 07:29:06","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-1287972/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-1287972/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":18842246,"identity":"d47fd863-dc01-4512-a793-91e4c780c365","added_by":"auto","created_at":"2022-03-03 22:23:32","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1332549,"visible":true,"origin":"","legend":"\u003cp\u003eSimulation lines from top to bottom represented the anterior and posterior surfaces of the cornea and ICL V4c, respectively. The blue dashed line represents the corneal topography axis connecting the fixation point and the corneal apex, and the yellow dashed line represents the ICL axis connecting the centers of the circles where the anterior and posterior surfaces of ICL V4c are located.\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-1287972/v1/bb81f734242b904bad629ea9.png"},{"id":18842248,"identity":"c72b34d5-c247-4774-811d-c9bf207f5ce1","added_by":"auto","created_at":"2022-03-03 22:23:32","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":7199155,"visible":true,"origin":"","legend":"\u003cp\u003e2A. Percentage of ICL V4c decentration and tilt at the six-month follow-up; 2B. Distribution of frequency, severity, and bothersome of visual symptoms after ICL V4c implantation.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-1287972/v1/1be15bf16f6b98eca5d064b2.png"},{"id":18842247,"identity":"d5d9a481-be84-4c29-8ae2-18a02d4c0e15","added_by":"auto","created_at":"2022-03-03 22:23:32","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":9576847,"visible":true,"origin":"","legend":"\u003cp\u003eDistribution of frequency, severity, and bothersome of visual symptoms after ICL V4c implantation.\u003c/p\u003e","description":"","filename":"figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-1287972/v1/0bc3381bf70ab2f0f135794c.png"},{"id":18842249,"identity":"142f8efb-28b3-4fa3-8064-877c5188d49e","added_by":"auto","created_at":"2022-03-03 22:23:35","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1229274,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-1287972/v1/2fb42a21-f1ee-4a9f-b66c-75de7d15749b.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eEffects of Tilt and Decentration of Visian Implantable Collamer Lens (ICL V4c) on Visual Quality: An Observational Study\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eIn 2005, the United States Food and Drug Administration approved the use of the Implantable Collamer Lens (ICL, STAAR Surgical, Nidau, Switzerland), which has since demonstrated its safety and efficacy as a treatment method for high myopia[\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. The ICL is reversible and maintains the central cornea integrity and promotes early recovery of visual acuity[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. The CentraFLOW technology in the Visian Implantable Collamer Lens (ICL V4c) contains a 360-\u0026micro;m central hole that promotes aqueous humor circulation, which reduces the incidence of cataract formation, decreases reduction of corneal endothelial cell and eliminates the need to perform neodymium:YAG (Nd: YAG) iridotomy before ICL implantation[\u003cspan additionalcitationids=\"CR7\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eStudies have shown that ICL V4c implantation produces better visual quality compared with laser-assisted in situ keratomileusis and small incision lenticule extraction; however, post-ICL implantation complications including high-order aberrations and coma aberrations increased still occur, as well as symptoms, including halo and glare[\u003cspan additionalcitationids=\"CR10 CR11 CR12\" citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTilt and decentration of the intraocular lens (IOL) can cause higher-order aberrations, which may lead to deterioration of visual function[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Therefore, ICL tilt and decentration effects on postoperative visual quality warrant investigation. The hole in the ICL provides a reference that allows observation of the position of the lens to evaluate the presence of tilt or decentration. The ICL hole is not usually located in the central pupil[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]; however, previous studies regarding the effect of ICL V4c decentration on visual acuity were in-vitro studies, and in-vivo experiments are lacking[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. The new generation anterior segment optical coherence tomography (AS-OCT) possesses a 1310-nm laser wavelength (CASIA2, Tomey, Japan), and has the advantages of high axial and transverse resolutions of 10 \u0026micro;m and 30 \u0026micro;m, respectively, high repeatability, and is non-mydriatic[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Furthermore, it can clearly display the anterior and posterior surfaces of the cornea, ICL, and crystalline lens. Additionally, AS-OCT automatically measures the tilt and decentration of the lens as a reference to the corneal topographic axis. This is the first study to aim to measure and analyze the post-implantation tilt and decentration of the ICL V4c and evaluate the effects on patients\u0026rsquo; visual quality.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eSubjects\u003c/h2\u003e \u003cp\u003e All patients were fully informed of the details and potential risks of the procedure, and written informed consent was obtained from all patients. The Ethics Committee of the Fudan University EENT Hospital Review Board approved the study protocol (No. 2016038), and the study adhered to the tenets of the Declaration of Helsinki.\u003c/p\u003e \u003cp\u003eIn this observational study, we recruited individuals who underwent ICL V4c implantation at our hospital. The inclusion criteria were: (1) age 20\u0026ndash;42 years; (2) stable refractive error (\u0026le;\u0026thinsp;0.50 D change per year in refractive error in the past 2 years); (3) minimum anterior chamber depth (ACD) of 2.8 mm and a minimum endothelial cell density (ECD) of 2000 cells/mm\u003csup\u003e2\u003c/sup\u003e; (4) no contact lens use for at least 2 weeks.\u003c/p\u003e \u003cp\u003eThe exclusion criteria were: (1) presence of comorbid eye disorders; (2) suspicion of keratectasia; and (3) presence of comorbid systemic diseases.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eVisian Implantable Collamer Lens\u003c/h2\u003e \u003cp\u003e The power calculation of the ICL V4c (STAAR Surgical, Nidau, Switzerland) was performed using a modified vertex formula based on the preoperative refractive parameters, according to the manufacturer\u0026rsquo;s instructions. The size of the implanted ICL V4c was determined from the white-to-white, horizontal corneal diameter, and ACD.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eSurgical procedure\u003c/h2\u003e \u003cp\u003eAn experienced surgeon (XZ) performed all ICL V4c implantations, as described previously[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Briefly, pupils were dilated preoperatively. A mark was made to show the horizontal axis on the limbus to allow the use of a Toric ICL. Using an injector cartridge, the ICL was implanted via a 3.0-mm temporal corneal incision. Then a moderate viscoelastic surgical agent (1% sodium hyaluronate) was injected into the anterior chamber and the ICL V4c lens was placed and positioned in the posterior chamber. The viscoelastic surgical agent was washed away entirely using a balanced salt solution, and a miotic agent was instilled. Postoperative medications included antibiotic, non-steroidal anti-inflammatory, steroidal, and artificial tears eye drops.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eFollow-up examination\u003c/h2\u003e \u003cp\u003eAll patients underwent preoperative and postoperative ocular examinations. The following main parameters were evaluated: uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), subjective manifest refraction, intraocular pressure (IOP, Canon, Japan), corneal topography and vault (Pentacam HR, Oculus Optikger\u0026auml;te GmbH, Wetzlar, Germany), wavefront aberration analysis (WASCA Wavefront Analyzer, Carl Zeiss Meditec, Germany), ECD (SP-95 2000P, Topcon Corporation, Japan), and ultrasound biomicroscopy (Quantel Medical, French). Patients were followed-up after 6 months postoperatively. The wavefront aberration is analyzed by Zernike polynomial and presented according to the Optic Society of America standard.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eAS-OCT measurement\u003c/h2\u003e \u003cp\u003eThe ocular anterior segment parameters were measured using AS-OCT (CASIA2; TOMEY, Nagoya, Japan). The chins and foreheads of all patients were fixed and gazed at a fixation target to fully expose the corneal limbus. A total of 128 anterior segment tomographic images of the entire circumference was obtained in only 2.4 s, and the measurements were repeated three times by the same examiner. Each OCT image clearly presents the anterior and posterior surfaces of the cornea, lens, and ICL. Sixteen images from 0\u0026deg; to 180\u0026deg; with different directions (0, 11, 23, 34, 45, 56, 68, 79, 90, 101, 113, 124, 135, 146, 158, and 169 degrees) were selected for each eye for analysis; the 0\u0026deg; and 90\u0026deg; images represented the horizontal and vertical orientation, respectively. Additionally, the maximum value of tilt or decentration within the 16 images represented the total tilt or total decentration value.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eTilt and decentration values\u003c/h2\u003e \u003cp\u003eThe AS-OCT images were analyzed using MATLAB software (R2018a, The MathWorks, Inc., Natick, MA, USA), which created four simulation lines from anterior to posterior; these lines were manually adjusted to coincide with the anterior and posterior corneal surfaces and ICL surfaces. Individual location values of the ICL were converted into coordinates (x and y). The software automatically calculates the (x, y) displacement of the anterior corneal surface apex and left and right endpoints of the central ICL hole. The corneal topography axis was defined as the line connecting the fixation point of the machine to the corneal apex. The ICL axis was defined as the line connecting the centers of the circles where the anterior and posterior surfaces of the ICL were located (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Decentration value was defined as the x-axis displacement between the center of the ICL hole and the corneal topography axis, while the tilt value was the angle between the ICL axis and the corneal topography axis. The values on the coordinate axes were expressed in pixels, which were converted to standard descriptive statistics (Unit: mm). Both the decentration and tilt values were analyzed as absolute values. All image analyses were performed independently by two examiners and the consistency of the results were evaluated. The intraclass correlation coefficient, Bland-Altman analysis plot, and cross-classification showed consistent results for the two analyses (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). All results were averaged from the two analyses.\u003c/p\u003e\u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eQuestionnaire design\u003c/h2\u003e \u003cp\u003eAll patients completed a questionnaire to report their subjective quality of vision during the follow-up at 6 months postoperatively (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA). The Quality of Vision (QoV) Questionnaire by McAlinden consists of a Rasch-tested, linear-scaled, 30-item instrument that includes three scales and provides a QoV score in terms of symptom frequency, severity, and bothersome[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. It is suitable for measuring QoV in patients with refractive correction. The 10 symptoms included glare, haloes, starbursts, hazy vision, blurred vision, distortion, double vision, fluctuation, focusing difficulties, and depth perception. Patients were asked regarding their overall satisfaction with the surgery, with 0 being dissatisfied and 10 being a perfect score of satisfied.\u003c/p\u003e\u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analyses\u003c/h2\u003e \u003cp\u003eStatistical analyses were performed using R software Version 3.4.3 (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://www.R-project.org\u003c/span\u003e\u003c/span\u003e). Continuous and categorical variables were expressed as means\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviations and frequencies (percentages), respectively. A paired t-test was used to analyze the difference between postoperative horizontal and vertical tilt or decentration. The generalized estimating equation model was used to analyze the correlation between tilt or decentration and aberration or visual quality score, which was adjusted for age, eye, preoperative refraction, and preoperative scotopic pupil at treatment. Statistical significance was set at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eSubjects\u0026rsquo; biometrics\u003c/h2\u003e \u003cp\u003eA total of 135 eyes from 69 patients (56 women and 13 men) with an average age of 28.88\u0026thinsp;\u0026plusmn;\u0026thinsp;5.46 years (20\u0026ndash;40 years) was enrolled in this observational clinical study; among them, 89 eyes were implanted with a Toric ICL. The preoperative mean CDVA was 1.01\u0026thinsp;\u0026plusmn;\u0026thinsp;0.17 (0.5 to 1.2) and the mean spherical equivalent (SE) was \u0026minus;\u0026thinsp;10.16\u0026thinsp;\u0026plusmn;\u0026thinsp;2.99 diopters (D) (-4.0 to -18.50 D). At the 6-month follow-up, the mean postoperative UDVA and CDVA were 1.12\u0026thinsp;\u0026plusmn;\u0026thinsp;0.23 (0.5 to 1.5) and 1.18\u0026thinsp;\u0026plusmn;\u0026thinsp;0.19 (0.6 to 1.5) respectively; the mean postoperative SE was \u0026minus;\u0026thinsp;0.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.44 (-2.25, 0.75). The efficacy index (postoperative UDVA/preoperative CDVA) was 1.11\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18 and the safety index (postoperative CDVA/preoperative CDVA) was 1.18\u0026thinsp;\u0026plusmn;\u0026thinsp;0.17. All 135 eyes achieved a postoperative SE within \u0026plusmn;\u0026thinsp;1.0 D of the attempted SE.\u003c/p\u003e \u003cp\u003eNo significant changes in IOP were observed between the preoperative (15.25\u0026thinsp;\u0026plusmn;\u0026thinsp;2.60 mmHg) and 6 months postoperative (14.87\u0026thinsp;\u0026plusmn;\u0026thinsp;2.82 mmHg) values (p\u0026thinsp;=\u0026thinsp;0.61). The number of ECD decreased by 0.6% compared with the preoperative ECD (2577.71\u0026thinsp;\u0026plusmn;\u0026thinsp;214.58 vs. 2568.66\u0026thinsp;\u0026plusmn;\u0026thinsp;229.75, p\u0026thinsp;=\u0026thinsp;0.61). The vault was 554.62\u0026thinsp;\u0026plusmn;\u0026thinsp;227.83 \u0026micro;m (165\u0026ndash;1360), and no clinical cataracts were observed. Additionally, 91.9% of patients had a scotopic pupil with a preoperative diameter\u0026thinsp;\u0026gt;\u0026thinsp;5.8 mm.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eTilt and decentration\u003c/h2\u003e \u003cp\u003eAt 6 months postoperatively, the detail results of total, horizontal and vertical tilt and decentration of all ICLs were presented in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\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\u003eThe tilt and decentration of ICL V4c postoperatively (N\u0026thinsp;=\u0026thinsp;135 eyes)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCharacteristic\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRange (Minimum, Maximum)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal tilt (\u0026deg;)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e2.54\u0026thinsp;\u0026plusmn;\u0026thinsp;1.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.35, 4.53\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHorizontal tilt (\u0026deg;)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1.78\u0026thinsp;\u0026plusmn;\u0026thinsp;1.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.05, 4.65\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVertical tilt (\u0026deg;)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1.22\u0026thinsp;\u0026plusmn;\u0026thinsp;0.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0, 3.85\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal decentration (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.21\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.019, 0.520\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHorizontal decentration (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.14\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0, 0.375\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVertical decentration (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.14\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0, 0.442\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003eICL V4c\u0026thinsp;=\u0026thinsp;Visian Implantable Collamer Lens;SD\u0026thinsp;=\u0026thinsp;standard deviation.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe horizontal tilt was significantly greater than the vertical tilt (p\u0026thinsp;=\u0026thinsp;0.000). Among them, 28.1% of the operated eyes were tilted within 2.0\u0026deg;, 91.85% within 4.0\u0026deg;, and the maximum did not exceed 5.0\u0026deg;. No significant difference was observed between the horizontal and vertical decentration (p\u0026thinsp;=\u0026thinsp;0.730). The distribution of the decentration was 47.4% within 0.2 mm, 98.5% within 0.5 mm, and the maximum decentration value did not exceed 0.6 mm (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eAberration\u003c/h2\u003e \u003cp\u003eAt the 6-month follow-up, both coma and trefoil were significantly increased, from 0.12\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09 and 0.09\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08 to 0.14\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09 (p\u0026thinsp;=\u0026thinsp;0.003) and 0.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09 (p\u0026thinsp;=\u0026thinsp;0.000), pre- and postoperatively respectively. In contrast no significant changes were observed in total higher-order and spherical aberrations after surgery (0.34\u0026thinsp;\u0026plusmn;\u0026thinsp;0.88 and 0.06\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05 preoperatively vs. 0.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10 and 0.07\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05 postoperatively, respectively; p\u0026thinsp;=\u0026thinsp;0.443 and 0.274).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eQuality of Vision questionnaire\u003c/h2\u003e \u003cp\u003eAt the 6-month follow-up, the most frequent visual symptoms reported by the patients were halos (93.33%), glare (54.81%), blurred vision (41.48%), and fluctuation (33.33%), which were only reported in 8.15%, 1.48%, 1.38%, and 0% of the operated eyes, respectively, as more than mildly bothersome to the patient. The frequency, severity, and bothersome scores of the 10 different postoperative visual symptoms are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB. The visual symptom frequency, severity, and bothersome scores were 33.87\u0026thinsp;\u0026plusmn;\u0026thinsp;12.29 (0\u0026ndash;59), 25.28\u0026thinsp;\u0026plusmn;\u0026thinsp;11.29 (0\u0026ndash;49), and 15.77\u0026thinsp;\u0026plusmn;\u0026thinsp;13.31 (0\u0026ndash;46), respectively.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eRelationship between tilt, decentration, and visual quality\u003c/h2\u003e \u003cp\u003eHorizontal, vertical, and total ICL tilt or decentration were not significantly correlated with postoperative CDVA, UDVA, higher-order aberration, coma, trefoil, and spherical aberration (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05). On the other hand, the total and horizontal tilt were positively correlated with frequency (p\u0026thinsp;=\u0026thinsp;0.000, r\u0026thinsp;=\u0026thinsp;0.414, and p\u0026thinsp;=\u0026thinsp;0.003, r\u0026thinsp;=\u0026thinsp;0.255, respectively), severity (p\u0026thinsp;=\u0026thinsp;0.000, r\u0026thinsp;=\u0026thinsp;0.367, and p\u0026thinsp;=\u0026thinsp;0.001, r\u0026thinsp;=\u0026thinsp;0.292, respectively), and bothersome (p\u0026thinsp;=\u0026thinsp;0.000, r\u0026thinsp;=\u0026thinsp;0.380, and p\u0026thinsp;=\u0026thinsp;0.000, r\u0026thinsp;=\u0026thinsp;0.421, respectively) scores of visual symptoms. No significant correlation was observed between vertical tilt, total decentration, horizontal decentration, vertical decentration, and visual symptom scores (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe clinical efficacy and long-term safety of ICL implantation for myopia correction have been widely recognized[\u003cspan additionalcitationids=\"CR2 CR3 CR4\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. However, technological and material developments have led to higher standards of postoperative visual quality in both doctors and patients. Moreover, some patients complained of their visual disturbances despite having visual acuities of 1.0 or better and refractions close to plano after surgeries. Our study is the first to measure and analyze tilt and decentration after ICL V4c implantation and evaluate their effects on the visual quality of patients.\u003c/p\u003e \u003cp\u003eThe CentralFLOW technology in the ICL V4c contains a 360-\u0026micro;m central hole, which provides a reference to fix the center of the ICL and allows observation of ICL decentration relative to the corneal topographic axis. Our study collected images using the AS-OCT, and analyzed the decentration and tilt values of the ICL using MATLAB software. The average total decentration was 0.21\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12 mm and the 98.5% decentration was within 0.5 mm at 6 months postoperatively. Several clinical studies have reported that the average decentration of IOL post-cataract surgery is approximately 0.23\u0026ndash;0.40 mm and the tilt is 3.03\u0026deg;\u0026ndash;7.00\u0026deg;[\u003cspan additionalcitationids=\"CR23\" citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Compared with these values, our findings are relatively lower; this discrepancy may be attributed to the location of the ICL haptics on the ciliary sulcus, which allows more stability and less influence from the suspensory ligament and other structures[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. A study of ICL that used the pupil center as the reference, reported that decentration of 48.9% and 93.6% of eyes were within 0.36 mm and 0.72 mm, respectively, and that of 93.6% eyes were within 0.72 mm after ICL implantation[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Notably, the selection criteria of the reference axis remain ununified. In corneal refractive surgery, significant decreases were observed in higher-order aberration and coma, and significant increase in contrast sensitivity when the corneal apex was used as the correction center rather than the center of the pupil[\u003cspan additionalcitationids=\"CR28\" citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. Since it is affected by pupil shape, the pupil axis may not be the best reference to evaluate the tilt and decentration of an ICL[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. The axis of corneal topography is a line connecting the fixed point of the machine and the first Purkinje image on the anterior surface of the cornea; while the apex of the cornea is a reflection point on the anterior surface of the cornea[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. In this study, we used the second generation AS-OCT to measure the tilt and decentration of ICL, which is not affected by the pupil shape and diameter with high repeatability.\u003c/p\u003e \u003cp\u003eA previous study reported that tilt and decentration of the IOL can induce image quality degradation in patients who developed postoperative coma, spherical aberration, and higher-order aberrations[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e], especially with an aspheric IOL[\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. Some studies have measured the maximum decentration and tilt of the aspheric IOL, which ensured the comparable visual quality between aspheric and standard IOL. Holladay reported that the critical decentration and tilt values are 0.4 mm and 7\u0026deg;, respectively; visual function will be affected once values are beyond these ranges[\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. The aberration or astigmatism caused by the tilt or decentration of aspheric IOL may affect the image quality of the retina, which inhibits clear image formation of the peripheral part of the retina, leading to glare, halo or monocular diplopia. The spherical shape of the optical zone of the ICL causes the decentration and tilt to have little influence on the objective visual quality. P\u0026eacute;rez-Vives[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] reported the results of an ICL decentration simulation test in vitro, and found that coma was directly correlated with the decentration value of the ICL and increased more with pupil diameter and higher refractive degree. Our study showed that tilt and decentration had no significant effect on postoperative aberrations, and had no significant correlation with postoperative UDVA and CDVA after adjusting for age, eye, preoperative refraction, and preoperative scotopic pupil, which is consistent with the results of Park[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Additionally, the effect of ICL decentration and tilt on postoperative visual acuity would be clinically insignificant.\u003c/p\u003e \u003cp\u003eThe reported visual symptoms of patients after ICL implantation in the order of most to least frequent were halo, glare, blurred vision, fluctuation, hazy vision, starbursts, focusing difficulties, double vision, depth perception, and distortion[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Similarly, Chen et al. found that patients with a small pupil diameter had a smaller halo radius after ICL implantation[\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. The largest optical area of ICL V4c was 5.8 mm. In our study, 91.9% of the eyes had dark pupil diameter larger than 5.8 mm; therefore, most patients occasionally experienced symptoms such as halo or glare. The total and horizontal tilt were positively correlated with the frequency, severity, and bothersome of visual symptoms scores. Eom et al. suggested that the halo is mainly due to the reflection of the inner wall of the central hole and posterior surface of ICL[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Eppig found that light through the central hole has no influence on the postoperative visual quality; however, the off-axis light will increase the intraocular reflection and scattering, which affects the postoperative visual quality[\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. Therefore, visual disturbances may be more evident with severe tilt.\u003c/p\u003e \u003cp\u003eThe limitations of this study were an observational study with short follow-up postoperative period and we will design further studies to observe the time-dependent changes of tilt and decentration results post-ICL implantation. And to overcome these limitations, both eyes were enrolled in this study, and we adjusted for eye laterality, patient age, and preoperative refraction during the statistical analysis to increase the accuracy and robustness of the results.\u003c/p\u003e \u003cp\u003eIn conclusion, ICL V4c implantation can obtain high visual quality and patient satisfaction. Although the degree of tilt and decentration after ICL V4c implantation was small, a positive effect on subjective visual quality was observed.\u003c/p\u003e"},{"header":"List Of Abbreviations","content":"\u003cp\u003eICL, Implantable Collamer Lens; UDVA, Uncorrected distance visual acuity; CDVA, Corrected distance visual acuity; AS-OCT, anterior segment-optical coherence tomography ACD, Anterior chamber depth; IOP, Intraocular pressure; ECD, Endothelial cell density; SE, spherical equivalent; D, diopters; QoV, Quality of Vision.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and Consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Ethics Committee of the Fudan University EENT Hospital Review Board approved the study protocol (No. 2016038), and the study adhered to the tenets of the Declaration of Helsinki. All methods were carried out in accordance with relevant guidelines and regulations. All patients were fully informed of the details and potential risks of the procedure, and written informed consent was obtained from all patients.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors thank Dr. Jian Gao of Zhongshan Hospital for providing statistical consultations. We would also like to thank all the patients participating in the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data that support the findings of this study are available from EENT hospital of Fudan university but restrictions apply to the availability of these data, which were used under license for the current study, and so are not publicly available. Data are however available from the authors upon reasonable request and with permission of EENT hospital of Fudan university.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by National Natural Science Foundation of China (Grant No. 81770955), Research Project Grant of Shanghai Municipal Health Commission (202040285), Project of Shanghai Science and Technology (Grant No.20410710100), Joint research project of new frontier technology in municipal hospitals (SHDC12018103), Clinical Research Plan of SHDC (SHDC2020CR1043B), Project of Shanghai Xuhui District Science and Technology (2020-015). The funding agencies had no role in study design, data collection and analysis, interpretation of data, or writing the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that there is no competing interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eLiterature screening and selection was performed by LN. XZ and PY participated in the design of the study. ZZ drafted the manuscript. ML and JZ carried out the statistical analysis. HM prepare and review of the manuscript. JH has designed the analysis program in the MATLAB software. XZ have given final approval of the version to be published. All authors read and approved the final manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eIgarashi A, Shimizu K, Kamiya K: \u003cb\u003eEight-year follow-up of posterior chamber phakic intraocular lens implantation for moderate to high myopia\u003c/b\u003e. Am J Ophthalmol 2014, \u003cb\u003e157\u003c/b\u003e(3):532\u0026ndash;539 e531.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJimenez-Alfaro I, Benitez del Castillo JM, Garcia-Feijoo J, Gil de Bernabe JG, Serrano de La Iglesia JM: \u003cb\u003eSafety of posterior chamber phakic intraocular lenses for the correction of high myopia: anterior segment changes after posterior chamber phakic intraocular lens implantation\u003c/b\u003e. 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J Cataract Refract Surg 2015, \u003cb\u003e41\u003c/b\u003e(11):2552\u0026ndash;2559.\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":"bmc-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"boph","sideBox":"Learn more about [BMC Ophthalmology](http://bmcophthalmol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/boph","title":"BMC Ophthalmology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Implantable Collamer Lens, myopia, decentration, tilt, visual quality ","lastPublishedDoi":"10.21203/rs.3.rs-1287972/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-1287972/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjectives\u003c/h2\u003e \u003cp\u003eTo investigate the tilt and decentration effects of the Visian Implantable Collamer Lens (ICL V4c) on visual quality after implantation.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA total of 135 eyes from 69 patients who underwent ICL V4c implantation were included in this study. Evaluation of spherical equivalent, uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and aberrations were performed 6-months postoperatively. The anterior segment parameters were collected using CASIA2 anterior segment-optical coherence tomography, and tilt and decentration of the ICL V4c were analyzed using MATLAB software. All patients received questionnaires to investigate the visual quality postoperatively.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe safety and effectiveness were 1.18\u0026thinsp;\u0026plusmn;\u0026thinsp;0.17 and 1.11\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18, respectively. No significant changes were observed regarding higher-order and spherical aberrations after the operation; however, coma and trefoil significantly increased compared to preoperative values. The average decentration was 0.21\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12 mm. The average tilt was 2.54\u0026thinsp;\u0026plusmn;\u0026thinsp;1.00\u0026deg;. Horizontal, vertical, and total values of tilt and decentration were not significantly associated with postoperative CDVA, UDVA, and aberrations. The most common visual symptom was halo, and 97.04% of patients had a satisfaction score\u0026thinsp;\u0026ge;\u0026thinsp;8. The total or vertical tilt was significantly positively correlated with the frequency, severity, and bothersome scores from the questionnaires.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eICL V4c implantation can obtain high visual quality and patient satisfaction. Although the degree of tilt and decentration after ICL V4c implantation was small, a positive effect on subjective visual quality was observed.\u003c/p\u003e","manuscriptTitle":"Effects of Tilt and Decentration of Visian Implantable Collamer Lens (ICL V4c) on Visual Quality: An Observational Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2022-03-03 22:23:30","doi":"10.21203/rs.3.rs-1287972/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2022-04-15T23:10:44+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2022-03-20T12:51:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"265d5ceb-5536-4bcb-9ae7-dfe24042db7a","date":"2022-03-05T12:06:44+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2022-03-05T02:41:47+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2022-03-05T02:34:21+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2022-03-04T04:41:48+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2022-03-01T13:10:08+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Ophthalmology","date":"2022-01-23T07:25:43+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"boph","sideBox":"Learn more about [BMC Ophthalmology](http://bmcophthalmol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/boph","title":"BMC Ophthalmology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"8cdd57f6-10ea-4fa1-9cfd-34eaa2349cb1","owner":[],"postedDate":"March 3rd, 2022","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2022-06-17T04:44:16+00:00","versionOfRecord":[],"versionCreatedAt":"2022-03-03 22:23:30","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-1287972","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-1287972","identity":"rs-1287972","version":["v1"]},"buildId":"J0_U0BvcaRcwD8yVFaRlm","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}