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Yang F, Yang Z, Zhao S, Huang Y. To Investigate the Changes in Corneal Curvature and Its Correlation with Corneal Epithelial Remodeling After Trans-PRK and FS-LASIK. Curr Eye Res 2024:1-7. [PMID: 38867491 DOI: 10.1080/02713683.2024.2361728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 05/23/2024] [Indexed: 06/14/2024]
Abstract
PURPOSE To evaluate curvature changes in different regions and their correlation with corneal epithelial remodeling in myopic patients undergoing femtosecond laser-assisted in situ keratomileusis (FS-LASIK) and transepithelial refractive keratectomy (Trans-PRK) after surgery. METHODS One hundred and sixty-three patients (163 right eyes) undergoing Trans-PRK and LASIK were evaluated for up to 6 months using anterior segment optical coherence tomography (OCT) to measure the epithelial thickness and corneal topography to measure corneal curvature in different areas (2 mm, 5 mm, and 7 mm). We calculated the curvature ΔK (ΔK = preoperative - postoperative), ΔK5-2 (ΔK5-2 = K5mm - K2mm), ΔK7-5 (ΔK7-5 = K7mm - K5mm), and the epithelial thickness ΔET5-2 (ΔET5-2 = ET5mm - ET2mm) and ΔET7-5 (ΔET7-5= ET7mm - ET5mm). RESULTS Corneal curvature flattened in each region of the two groups (all p < 0.001) and gradually steepened during the follow-up period. The Trans-PRK group flattened more significantly within 2 mm and 5 mm, while the FS-LASIK group at 7 mm. Both groups of ΔK decreased over time. Both groups of ΔK5-2 and ΔK7-5 gradually decreased during the follow-up period (P5-2=0.025 and P7-5 < 0.001 for Trans-PRK, P5-2 = 0.011 and P7-5 < 0.001 for FS-LASIK). The corneal epithelium of the two groups gradually thickened during the follow-up period, with Trans-PRK significantly thickening in the central and peripheral regions and FS-LASIK in the central and paracentral regions. There is a significant correlation between the ΔK5-2 and ΔET5-2, ΔK7-5 and ΔET7-5 (all r > 0.37, p < 0.001). CONCLUSIONS All groups showed significant curvature flattening after surgery and gradually steepening during the follow-up period. The corneal epithelium thickness in both groups of 17 regions became thicker,. In contrast, Trans-PRK group showed more significant thickening to the periphery and the central 5 mm area of the FS-LASIK. This study indicates a significant positive correlation between differences in epithelial thickening in different regions and differences in curvature changes in the corresponding areas PRK, FS-LASIK, curvature, corneal epithelial thickness.
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Affiliation(s)
- Fan Yang
- Eye Institute and School of Optometry, Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Zheng Yang
- Eye Institute and School of Optometry, Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Shaozhen Zhao
- Eye Institute and School of Optometry, Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Yue Huang
- Eye Institute and School of Optometry, Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Tianjin Medical University Eye Hospital, Tianjin, China
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Ye Y, Hou X, Yu N, Chen P, Zhuang J, Yu K. Corneal Epithelial Remodeling Induced by Photorefractive Keratectomy Enhancement After Small-Incision Lenticule Extraction. Transl Vis Sci Technol 2024; 13:14. [PMID: 38231497 PMCID: PMC10795581 DOI: 10.1167/tvst.13.1.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 11/25/2023] [Indexed: 01/18/2024] Open
Abstract
Purpose To assess changes in corneal epithelial thickness (ET) within 9-mm diameter cornea after photorefractive keratectomy (PRK) retreatment after small-incision lenticule extraction (SMILE). Methods A total of 28 eyes of 19 patients with mean spherical equivalent of -1.30 ± 0.60 D who underwent retreatment after SMILE were included in this retrospective study. ET mapped across a 9-mm diameter area was obtained using wide-field optical coherence tomography (OCT) before and at one, three, and six months after surgery. The ET changes were compared between the different time points and analyzed zones. Results Before enhancement, the ET were 63.64 ± 6.01 µm and 61.25 ± 4.32 µm in central and paracentral zones, respectively. The ET of central and paracentral zones significantly decreased at one month and subsequently increased until six months. Six months after surgery, significant epithelial thickening occurred in 2- to 9-mm diameter cornea (all P < 0.05), whereas no significant change was observed in central 2-mm diameter cornea (P = 0.460). There was no significant difference in the ET between the central and paracentral zones (P = 1.00). The degree of myopic correction significantly correlated with the average ET in the central (P = 0.046) and paracentral (P = 0.033) zones at six months after PRK enhancement. No significant correlation was detected between the average ET of all zones and the postoperative spherical equivalent at six months after surgery (all P > 0.05). Conclusions PRK enhancement did not alter the overall trend of corneal epithelial remodeling induced by SMILE. An asymmetric and flatter lenticule-like pattern of epithelial remodeling was observed six months after surgery, which did not affect the refractive outcomes. Translational Relevance An asymmetric and centrally flattened lenticule-like pattern of epithelial remodeling was observed after PRK enhancement. Surgeons should consider expanding the intended optical zones for enhancement surgery after SMILE.
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Affiliation(s)
- Yiming Ye
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Xiangtao Hou
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Na Yu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Pei Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Jing Zhuang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Keming Yu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
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Lyra AFV, Alves EM, Montenegro AA, Parente NS, Cardoso MT, Alves LM, Maia CB, Fontes BM, Nose W. Corneal Higher Order Aberrations and Epithelial Remodeling With Femtosecond Laser-Assisted LASIK Topography-guided and Customized Asphericity Ablation in the Contralateral Eye: A Randomized, Double-Blind, Prospective Study. J Refract Surg 2023; 39:751-758. [PMID: 37937761 DOI: 10.3928/1081597x-20230925-03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
PURPOSE To evaluate refractive results, corneal higher order aberrations (HOAs), and epithelial remodeling in the preoperative and postoperative period of regular corneas that had topography-guided femtosecond laser-assisted laser in situ keratomileusis (LASIK) (Contoura WaveLight; Alcon Laboratories, Inc) and compare them with the contralateral eye that underwent ablation customized by asphericity (Custom-Q WaveLight; Alcon Laboratories, Inc) in myopic eyes with or without astigmatism. METHODS A prospective, randomized, and double-blind study was conducted. Patients underwent preoperative and postoperative epithelial mapping and corneal tomography to assess the epithelial thickness map, HOAs of the corneal anterior surface, visual acuity, and refractive evaluation. RESULTS This study enrolled 96 normal eyes of 48 patients. Uncorrected distance visual acuity of 20/20 or better was achieved in 97% of patients and gains in corrected distance visual acuity and effectiveness in correcting refractive astigmatism were similar in both techniques. Seventeen sectors of the corneal epithelium map were assessed by spectral-domain optical coherence tomography and no significant differences were found between techniques preoperatively and postoperatively (P > .05). HOA root mean square, coma Z3±1, trefoil Z3-3, and tissue consumption exhibited statistically significant between-technique differences (P < .05). CONCLUSIONS The Contoura and Custom-Q techniques were similar with respect to refractive and visual outcomes after 3 months, as well as in epithelial remodeling. The Contoura provides lower postoperative HOA root mean square, coma Z3±1, and trefoil Z3-3 values, but the techniques showed no differences in the correction of the corneal astigmatic wavefront component and in the spherical aberration after 3 months. [J Refract Surg. 2023;39(11):751-758.].
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Onishi AC, Lee-Choi C, Marvasti AH. Topography-guided excimer laser ablation. Curr Opin Ophthalmol 2023; 34:296-302. [PMID: 37014746 DOI: 10.1097/icu.0000000000000957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Abstract
PURPOSE OF REVIEW Currently, the most commonly performed corneal refractive surgery is laser-assisted in-situ keratomileusis (LASIK). Customized forms of LASIK have been developed, which have allowed for improved outcomes and the enhanced correction of higher order aberrations (HOAs). This review discusses one form of custom LASIK, topography-guided LASIK, including factors involved in preoperative planning, and advantages and disadvantages compared with other forms of keratorefractive surgery. RECENT FINDINGS Various treatment-planning approaches addressing discrepancies between the refractive and topographic astigmatic magnitude and axis have been used successfully, although there is debate regarding a superior method in the literature. SUMMARY There are many forms of custom LASIK, which provide excellent outcomes. Topography-guided LASIK may be of particular use in highly aberrated corneas and may also provide outstanding outcomes in healthy eyes given its emphasis on treating the primary refractive surface of the eye.
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Affiliation(s)
- Alex C Onishi
- Department of Ophthalmology, Stein Eye Institute, David Geffen School of Medicine at the University of California, Los Angeles
| | | | - Amir H Marvasti
- Department of Ophthalmology, Stein Eye Institute, David Geffen School of Medicine at the University of California, Los Angeles
- Coastal Vision Medical Group, Orange, California, USA
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Yousif MO, Elkitkat RS, Edrees ES, Alaarag NA. Introducing a Revised Tissue Saving Protocol for Combined Topography-Guided Photorefractive Keratectomy and Cross-Linking in Keratoconic Corneas. Cornea 2023; 42:755-765. [PMID: 36728310 DOI: 10.1097/ico.0000000000003225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Accepted: 11/26/2022] [Indexed: 02/03/2023]
Abstract
PURPOSE The aim of this study was to introduce a revised tissue-saving technique for combined topography-guided photorefractive keratectomy (PRK) and cross-linking for keratoconus (KC) treatment and to evaluate its efficacy, safety, and stability. METHODS This retrospective, noncontrolled study was performed at Maadi Eye Subspecialty Center and Eye Care Center, Cairo, Egypt. The technique was performed on virgin keratoconic corneas with 3 different morphological patterns of ectasia. It involves performing topography-guided PRK before epithelial removal, followed by customized phototherapeutic keratectomy (PTK) that is tailored to each cornea after studying the treatment profile on the laser treatment screen. The electronic medical records were explored for preoperative and postoperative data, including subjective refraction and topographic data (using Sirius topographer). RESULTS The study was conducted on 123 eyes of 93 patients with a mean age of 27.98 years ±6.06. The follow-up ranged from 6 to 36 months (mean ± SD of 16.2 months ±10.4). The results showed statistically nonsignificant differences among the 3 ectasia subgroups in treatment spherical equivalent, treatment maximum depth, thickness of removed epithelium, and thinnest residual stromal bed. There were statistically significant differences in almost all values between the preoperative and postoperative data, with significant postoperative patients' improvement ( P value <0.001). The subgroups' results were almost the same as the whole cohort's results. The safety and efficacy indices of the performed procedure showed remarkably high values (1.48 ± 0.21 and 0.87 ± 0.40, respectively). CONCLUSIONS This revised protocol for KC management maximally preserves stromal tissue with proven efficacy, safety, and stability.
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Affiliation(s)
- Mohamed Omar Yousif
- Assistant Professor of Ophthalmology, Faculty of Medicine, Ain Shams University
- Cornea and Refractive Surgery Consultant, Maadi Eye Subspecialty Center
| | - Rania Serag Elkitkat
- Assistant Professor of Ophthalmology, Faculty of Medicine, Ain Shams University
- Watany Eye Hospital
- Watany Research and Development Center
- Head of Ophthalmology Department, Faculty of Medicine, MTI University
| | - Eman Samir Edrees
- Lecturer of Ophthalmology, Faculty of Medicine, Ain Shams University; and
- Maadi Eye Subspecialty Center, Cairo, Egypt
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Zhu M, Xin Y, Vinciguerra R, Wang Z, Warsame AM, Wang C, Zhu D, Qu Z, Wang P, Zheng X, Wang J, Wang Q, Ye Y, Chen S, Bao F, Elsheikh A. Corneal Epithelial Remodeling in a 6-Month Follow-up Period in Myopic Corneal Refractive Surgeries. J Refract Surg 2023; 39:187-196. [PMID: 36892243 DOI: 10.3928/1081597x-20230113-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/10/2023]
Abstract
PURPOSE To investigate corneal epithelial thickness changes during a 6-month follow-up period after transepithelial photorefractive keratectomy (tPRK), femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK), and small incision lenticule extraction (SMILE). METHODS This prospective study included 76 eyes of 76 participants who underwent myopic refractive surgery (23 FS-LASIK, 22 SMILE, and 31 tPRK). Epithelial thickness and anterior curvature were averaged over 4 regions (subdivided into 25 areas) and measured by spectral-domain optical coherence tomography and Scheimpflug tomography before the operation (pre) and at 1 or 3 days (pos1-3d), 1 week (pos1w), and 1 month (pos1m), 3 months (pos3m), and 6 months (pos6m) postoperatively. RESULTS The epithelial thickness of the three groups was similar in both the pre and pos6m (all P > .05), but the tPRK group fluctuated the most during the follow-up period. The largest increase was in the inferior-temporal paracentral area (7.25 ± 2.58 μm for FS-LASIK; 5.79 ± 2.41 μm for SMILE; 4.88 ± 5.84 μm for tPRK; all P < .001). Only the epithelial thickness of tPRK increased from pos3m to pos6m (P < .05), whereas all changes for FS-LASIK and SMILE were not significant (P > .05). A positive correlation of thickness changes with curvature gradient in the paracentral region of tPRK was found (r = 0.549, P = .018), but not in other regions in all groups. CONCLUSIONS Epithelial remodeling followed different trends after different surgeries from the early postoperative stage onward, but exhibited similar values at pos6m. Although remodeling after FS-LASIK and SMILE stabilized by pos3m, it remained unstable at pos6m after tPRK. These changes may affect corneal profile and lead to deviation from the intended surgical outcome. [J Refract Surg. 2023;39(3):187-196.].
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Liu C, Luo T, Fang X, Hu M, Su Y, Li J, Wang Y. Clinical results of topography-guided laser-assisted in situ keratomileusis using the anterior corneal astigmatism axis and manifest refractive astigmatism axis. Graefes Arch Clin Exp Ophthalmol 2023; 261:247-256. [PMID: 35895108 DOI: 10.1007/s00417-022-05775-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 07/02/2022] [Accepted: 07/19/2022] [Indexed: 01/04/2023] Open
Abstract
PURPOSE To evaluate the clinical results of primary topography-guided femtosecond laser-assisted in situ keratomileusis (TG-FS-LASIK) using the Pentacam-measured anterior corneal astigmatism axis (ACA) or manifest refractive astigmatism axis (MRA). METHODS In this prospective cohort study, all eyes were treated with primary TG-FS-LASIK using the manifest cylinder. Thirty-two right eyes were treated using ACA with axis disparity > 5° in the experimental group, and 32 right eyes were treated using MRA with axis disparity ≤ 5° in the control group. Visual, refractive outcomes, and corneal higher-order aberrations were evaluated. Vector analysis of astigmatism was performed using Alpins method with the ASSORT software. RESULTS The mean logMAR UDVA in the experimental group was - 0.12 ± 0.06, - 0.05 ± 0.08, and - 0.08 ± 0.08 at 1-week, 1-month, and 3-month follow-up, whereas - 0.05 ± 0.06, - 0.12 ± 0.06, and - 0.14 ± 0.06 in the control group (p = 0.017, p < 0.001, and p = 0.003). At 3-month follow-up, 79% eyes achieved a UDVA of 20/16 or better, 9% gained one line of corrected distance visual acuity, the mean manifest cylinder was - 0.375 ± 0.254 D, 84% showed a manifest cylinder within ± 0.50 D, the mean magnitude of difference vector was 0.41 ± 0.35 D, the mean absolute angle of error (AE) was 7.36 ± 6.21°, and 41% exhibited an arithmetic AE within ± 5° in the experimental group, whereas 94%, 19%, - 0.203 ± 0.148 D, 100%, 0.21 ± 0.15 D, 3.39 ± 3.68°, and 69% in the control group (all p < 0.05). The postoperative and preoperative corneal spherical aberrations were comparable in both groups (p > 0.05). CONCLUSION Primary topography-guided FS-LASIK using Pentacam-measured anterior corneal astigmatism axis exhibited slightly inferior clinical results to that using the manifest refractive astigmatism axis. Both methods achieved comparable postoperative and preoperative corneal spherical aberrations.
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Affiliation(s)
- Chunlei Liu
- Clinical College of Ophthalmology, Tianjin Medical University, Tianjin, China.,Tianjin Key Lab of Ophthalmology and Visual Science, Tianjin Eye Hospital, Tianjin, China.,Refractive Surgery Department, Shenyang Aier Eye Hospital, Shenyang, China
| | - Tian Luo
- Pathology Department, Jinan Maternal and Child Health Hospital, Jinan, China
| | - Xuejun Fang
- Refractive Surgery Department, Shenyang Aier Eye Hospital, Shenyang, China
| | - Ming Hu
- Refractive Surgery Department, Yantai Aier Eye Hospital, Yantai, China
| | - Yun Su
- Refractive Surgery Department, Shenyang Aier Eye Hospital, Shenyang, China
| | - Jing Li
- Refractive Surgery Department, Shaanxi Eye Hospital, Xi'an People's Hospital (Xi'an Fourth Hospital), Affiliated Guangren Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, China
| | - Yan Wang
- Clinical College of Ophthalmology, Tianjin Medical University, Tianjin, China. .,Tianjin Key Lab of Ophthalmology and Visual Science, Tianjin Eye Hospital, Tianjin, China.
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Refractive Effect of Epithelial Remodelling in Myopia after Transepithelial Photorefractive Keratectomy. VISION (BASEL, SWITZERLAND) 2022; 6:vision6040074. [PMID: 36548936 PMCID: PMC9781313 DOI: 10.3390/vision6040074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 11/15/2022] [Accepted: 12/08/2022] [Indexed: 12/15/2022]
Abstract
(1) Introduction: We analysed epithelial changes after the treatment of moderate myopia with transepithelial photorefractive keratectomy. (2) Materials and Methods: We used optical coherence tomography data and analysed changes in the stroma and epithelium after ablation. We aimed to ascertain how much epithelium hyperplasia occurred after TransPRK; for this, we used data from 50 eyes treated with TransPRK with the AMARIS 1050 Hz, with a minimum follow-up of 4 months. (3) Results: The measured epithelial changes corresponded to a less than 0.1 ± 0.2D of spherical effect, less than 0.2 ± 0.2D of astigmatic effect, and less than 0.5 ± 0.2D of comatic effect. (4) Conclusions: The changes in epithelial thickness after aberration-neutral transepithelial photorefractive keratectomy for moderate myopia were very small, indicating a low level of epithelial hyperplasia without resembling a regression-inducing lentoid.
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Saleh S, Epp LJ, Manche EE. Effect of corneal epithelial remodeling on visual outcomes of topography-guided femtosecond LASIK. J Cataract Refract Surg 2022; 48:1155-1161. [PMID: 35333817 DOI: 10.1097/j.jcrs.0000000000000940] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 03/17/2022] [Indexed: 11/25/2022]
Abstract
PURPOSE To assess the effect of epithelial remodeling on visual outcomes over a 9 mm diameter corneal surface after topography-guided laser in situ keratomileusis (LASIK) for myopia correction using spectral-domain anterior segment optical coherence tomography (AS-OCT). SETTING Outpatient clinical practice at the Stanford University Byers Eye Institute in Palo Alto, California. DESIGN Prospective nonrandomized observational study. METHODS Visual acuity, including uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA), 5% and 25% contrast sensitivity CDVA, manifest refraction, and corneal epithelial thickness after topography-guided femtosecond LASIK were analyzed. Corneal epithelial thickness was mapped across 13 sections and 3 concentric zones using AS-OCT preoperatively and at 1 month, 3 months, 6 months, and 12 months postoperatively. RESULTS 60 eyes of 30 patients with a mean age of 32.8 years (range 23 to 52 ± 7.03 years) undergoing myopic LASIK correction were assessed. In eyes with complete follow-up data (n = 30), mean preoperative UDVA was logMAR 1.48 ± 0.45 and logMAR -0.11 ± 0.08 at postoperative 12 months. Mean preoperative CDVA was logMAR -0.08 ± 0.11 and logMAR -0.13 ± 0.07 at 12 months. Linear mixed modeling demonstrated a significant correlation between improvement in UDVA and decreased superior and nasal corneal epithelial thickness and between improvement in CDVA and increased central epithelial thickness 12 months postoperatively. CONCLUSIONS Improvement in UDVA and CDVA at 12 months after topography-guided femtosecond LASIK was correlated with nonuniform epithelial remodeling, including epithelial thickening in the central zone and thinning in the superior and nasal sections as measured by AS-OCT.
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Affiliation(s)
- Solin Saleh
- From the Byers Eye Institute, Stanford University School of Medicine, Palo Alto, California
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Evaluation of morphological features: femtosecond-LASIK flap vs. SMILE cap, and the effects on corneal higher-order aberrations. Graefes Arch Clin Exp Ophthalmol 2022; 260:3993-4003. [PMID: 36166075 DOI: 10.1007/s00417-022-05841-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 08/14/2022] [Accepted: 09/20/2022] [Indexed: 11/04/2022] Open
Abstract
PURPOSE The aim of this study is to evaluate morphological features of corneal flap/cap and the correlations with corneal higher-order aberrations (HOAs) changes after femtosecond laser in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE). METHODS This was a retrospective study. Pre- and postoperative (1 and 3 months) corneal HOAs were assessed with Pentacam HR. The corneal flap/cap thickness at 32 points (± 1.5 mm, ± 2 mm, ± 2.5 mm, and ± 3 mm from the corneal vertex on meridian 0°/45°/90°/135°) were measured using anterior segment optical coherence tomography at 3 months postoperatively. Morphological features of corneal flap/cap including predictability (P), uniformity (U), and symmetry (S) were calculated and used for correlation analysis with corneal HOAs changes. RESULTS Eighty-six eyes (44 patients) and ninety-six eyes (50 patients) were involved in FS-LASIK and SMILE groups, respectively. Significant thicker corneal flap/cap than the predicted was observed at each measuring point and meridian in both groups (difference > 2.225 μm, the within-subject standard deviation over 6-mm optical zone). There was no statistically significant difference in predictability of corneal flap/cap thickness, while U6 mm (P < .0001), U0 (P < .001), U45 (P = .002), U90 (P < .0001), U135 (P = .004), S6 mm (P < .0001), S0 (P < .001), and S90 (P < .0001) over 6 mm zone were less in SMILE than in FS-LASIK. The changes of corneal tHOAs, Z (3, - 1), Z (3, 1), and SA were significantly correlated with morphological features of corneal flap/cap. CONCLUSION Both FS-LASIK and SMILE had good predictability in flap or cap thickness, while the uniformity and symmetry of SMILE cap were better than FS-LASIK flap. The quality of flap/cap was closely associated with the changes of corneal HOAs.
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Gao HB, Pan ZG, Shen MX, Lu F, Li H, Zhang XQ. KeratoScreen: Early Keratoconus Classification With Zernike Polynomial Using Deep Learning. Cornea 2022; 41:1158-1165. [PMID: 35543584 DOI: 10.1097/ico.0000000000003038] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 02/16/2022] [Indexed: 12/13/2022]
Abstract
PURPOSE We aimed to investigate the usefulness of Zernike coefficients (ZCs) for distinguishing subclinical keratoconus (KC) from normal corneas and to evaluate the goodness of detection of the entire corneal topography and tomography characteristics with ZCs as a screening feature input set of artificial neural networks. METHODS This retrospective study was conducted at the Affiliated Eye Hospital of Wenzhou Medical University, China. A total of 208 patients (1040 corneal topography images) were evaluated. Data were collected between 2012 and 2018 using the Pentacam system and analyzed from February 2019 to December 2021. An artificial neural network (KeratoScreen) was trained using a data set of ZCs generated from corneal topography and tomography. Each image was previously assigned to 3 groups: normal (70 eyes; average age, 28.7 ± 2.6 years), subclinical KC (48 eyes; average age, 24.6 ± 5.7 years), and KC (90 eyes; average age, 25.9 ± 5.4 years). The data set was randomly split into 70% for training and 30% for testing. We evaluated the precision of screening symptoms and examined the discriminative capability of several combinations of the input set and nodes. RESULTS The best results were achieved using ZCs generated from corneal thickness as an input parameter, determining the 3 categories of clinical classification for each subject. The sensitivity and precision rates were 93.9% and 96.1% in subclinical KC cases and 97.6% and 95.1% in KC cases, respectively. CONCLUSIONS Deep learning algorithms based on ZCs could be used to screen for early KC and for other corneal ectasia during preoperative screening for corneal refractive surgery.
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Affiliation(s)
- He-Bei Gao
- Division of Health Sciences, Hangzhou Normal University, Hangzhou, China
- Department of Information, Wenzhou Polytechnic, Wenzhou, China
| | - Zhi-Geng Pan
- School of Artificial Intelligence, Nanjing University of Information Science & Technology, Nanjing, China
| | - Mei-Xiao Shen
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China ; and
| | - Fan Lu
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China ; and
| | - Hong Li
- College of Computer Science and Artificial Intelligence, Wenzhou University, Wenzhou, China
| | - Xiao-Qin Zhang
- College of Computer Science and Artificial Intelligence, Wenzhou University, Wenzhou, China
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Evaluation of Wide Corneal Epithelial Remodeling after Small Incision Lenticule Extraction (SMILE) with Wide-Field Optical Coherence Tomography. J Ophthalmol 2022; 2022:8764103. [PMID: 35355880 PMCID: PMC8958109 DOI: 10.1155/2022/8764103] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 02/18/2022] [Indexed: 11/18/2022] Open
Abstract
Purpose This study aims to assess the corneal epithelial remodeling within a 9 mm diameter zone induced by small incision lenticule extraction (SMILE) and evaluate its relationship with the refractive outcomes. Methods A total of 64 eyes of 64 patients were included. Wide-field optical coherence tomography (OCT) was used to measure the epithelial thickness (ET) across a 9 mm diameter area, preoperatively, and after one day, one week, one month, three months, and six months postoperatively. The ET changes were compared among the different time points and analyzed zones. Results The ET increases from one week to three months and stabilized from three months to six months. Compared to the preoperative values, the mean ET changes at six months in central (2 mm), paracentral (2-5 mm), mid-peripheral (5-7 mm), and peripheral (7-9 mm) zones were 4.37, 4.36, 1.61, and -1.59 μm, respectively. The correlation between the epithelial thickening and the amount of myopia correction was positive in central (P = 0.001) and paracentral zones (P < 0.001) and negative in peripheral zone (P = 0.006). The intended diameter of the optical zone was negatively related to epithelial hyperplasia in the central (P = 0.020) and paracentral zone (P = 0.006), and the correlation was positive in the mid-peripheral zone (P = 0.001). The epithelial thickening of central zone (P = 0.012) and the difference of mean ET between central and paracentral zone (P = 0.020) were negatively related to the spherical equivalent at six months. Conclusion An asymmetric lenticule-like pattern of epithelial remodeling occurred in 9 mm diameter cornea at six months after myopic SMILE. The epithelial remodeling may affect the refractive outcomes of SMILE.
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Comparison of Epithelial Thickness Mapping in Normal Corneas with Different Types of Astigmatism. Optom Vis Sci 2022; 99:443-448. [DOI: 10.1097/opx.0000000000001886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Bohac M, Biscevic A, Shijakova V, Gabric I, Gabric K, Patel S. Comparison between the change in total corneal astigmatism and actual change in refractive astigmatism in transepithelial photorefractive keratectomy (tPRK), laser in situ keratomileusis (LASIK) and femtosecond laser assisted laser in situ keratomileusis (FsLASIK). Eur J Ophthalmol 2021; 32:2638-2645. [PMID: 34761687 DOI: 10.1177/11206721211059327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE To compare changes in astigmatism by refraction and total corneal astigmatism after tPRK, LASIK and FsLASIK. SETTING Specialty Eye Hospital Svjetlost, Zagreb, Croatia. DESIGN Partially masked, semi-randomized, prospective, case-by-case, interventional, clinical study. METHODS Patients with a stable refraction (-0.75DS to -8.00DS, astigmatism ≤1.00DC) underwent tPRK, LASIK or FsLASIK without complication. Astigmatism was measured at both corneal surfaces over the central 3.2 mm zone (approximately using Pentacam HRTM) preoperatively and 3 months postoperatively. Pentacam and refraction data were subjected to vector analysis to calculate the surgically induced changes in i) total corneal astigmatism (SIATCA) ii) any astigmatism by refraction (SIAR) and the vectorial difference (DV) between SIATCA and SIAR. RESULTS Reporting key findings (p < .01), there was a significant difference between mean SIATCA and SIAR powers after tPRK (75eyes) but not after LASIK (100eyes) or FsLASIK (100eyes). Mean (±sd,95% CIs) values for DV powers were, tPRK -1.13DC(±0.71, -1.29 to -0.97), LASIK -0.39DC(±0.23,-0.44 to -0.34), FsLASIK -0.55DC(±0.38,-0.62 to -0.47). The differences were significant. For the tPRK and FsLASIK cases, linear regression revealed significant associations between I) SIATCA (x) &DV (z) powers (tPRK z = 1.586x-0.179, r  =  0.767, p < .01; FsLASIK z  =  0.442x-0.303, r  =  .484,p < .01), II) sines of SIATCA (x1) &DV (z1) axes (tPRK, z1 = 0.523 × 1 + 0.394, r = .650,p < .01; FsLASIK z1 = 0.460 × 1-0.308, r = .465,p < .01). CONCLUSIONS tPRK is more prone to unintended changes in astigmatism. The difference between SIATCA & SIAR after tPRK or FsLASIK is mediated by SIATCA. Photoablating deeper regions of the cornea reduces the gap between SIATCA & SIAR.
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Affiliation(s)
- Maja Bohac
- 448692Specialty Eye Hospital "Svjetlost", Zagreb, Croatia, School of Medicine University of Rijeka, Croatia
| | - Alma Biscevic
- 448692Specialty Eye Hospital "Svjetlost", Zagreb, Croatia, School of Medicine University of Rijeka, Croatia
| | - Violeta Shijakova
- 448692Specialty Eye Hospital "Svjetlost", Zagreb, Croatia, School of Medicine University of Rijeka, Croatia.,Eye Clinic Sistina Oftalmologija, Skopje, Republic of North Macedonia
| | - Ivan Gabric
- 448692Specialty Eye Hospital "Svjetlost", Zagreb, Croatia, School of Medicine University of Rijeka, Croatia
| | - Kresimir Gabric
- 448692Specialty Eye Hospital "Svjetlost", Zagreb, Croatia, School of Medicine University of Rijeka, Croatia
| | - Sudi Patel
- 448692Specialty Eye Hospital "Svjetlost", Zagreb, Croatia, School of Medicine University of Rijeka, Croatia
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Gui X, Zhang R, Li S, Zhao N, Zhang HR, Zhou YK, Huan CY, Zhao CY, Wang HY, Song HY, Shen W, Zhang JH. Comparative analysis of the clinical outcomes between wavefront-guided and conventional femtosecond LASIK in myopia and myopia astigmatism. Int J Ophthalmol 2021; 14:1581-1588. [PMID: 34667736 DOI: 10.18240/ijo.2021.10.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Accepted: 08/20/2021] [Indexed: 11/23/2022] Open
Abstract
AIM To compare the clinical outcomes of wavefront guided femtosecond LASIK (WFG LASIK) and conventional femtosecond LASIK (NWFG LASIK) in eyes with myopia and myopia astigmatism. METHODS This was a retrospective, nonrandomized, comparative investigation enrolling 236 eyes of 122 patients (18-50y) with low & moderate and high myopia. The WFG group including 97 eyes (50 patients) undergone WFG LASIK and the NWFG group including 139 eyes (72 patients) undergone conventional LASIK. Mean efficacy index, high order aberrations (HOAs), pupil size and the quality of visual questionnaire were evaluated 6mo postoperatively. RESULTS There is no difference between WFG group (-0.054±0.049 in logMAR) and NWFG group (-0.040±0.056) in uncorrected distance visual acuity (UDVA) postoperatively. The myopia astigmatism is higher in WFG group than that in NWFG group (P<0.05). However, the mean efficacy index (MEI) in the WFG group (1.09±0.106) is better than that in the NWFG group (1.036±0.124; P<0.001). Increased HOAs were observed in NWFG group (0.30±0.196) than that in WFG group (0.146±0.188; P<0.001). The pupil size is larger in WFG group (5.15±0.76 mm) than that in NWFG group (4.32±0.52 mm). The patients are satisfied with the clinical surgery, yet WFG group showed better visual quality using the questionnaire survey. Meanwhile, high myopia would result in worse MEI, HOAs and visual quality than low & moderate myopia. CONCLUSION WFG and NWFG FS-LASIK are both effective and safe procedures to correct low & moderate and high myopia, but WFG FS-LASIK gives a better postoperative MEI, aberrometric control and predictable outcome. Meanwhile, WFG FS-LASIK is better than NWFG FS-LASIK in correction of myopia astigmatism. Low & moderate myopia allow better clinical outcomes than high myopia using any surgical method.
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Affiliation(s)
- Xiao Gui
- Department of Ophthalmology, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - Rui Zhang
- Department of Ophthalmology, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - Sha Li
- Department of Ophthalmology, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - Na Zhao
- Department of Ophthalmology, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - Hao-Rui Zhang
- Department of Ophthalmology, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - Yu-Kun Zhou
- Department of Ophthalmology, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - Chen-Yang Huan
- Department of Ophthalmology, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - Chun-Yan Zhao
- Department of Ophthalmology, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - Hong-Ying Wang
- Department of Ophthalmology, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - Hong-Yuan Song
- Department of Ophthalmology, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China.,Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - Wei Shen
- Department of Ophthalmology, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - Jian-Hua Zhang
- Department of Ophthalmology, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
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Comparison of the optical quality after SMILE and FS-LASIK for high myopia by OQAS and iTrace analyzer: a one-year retrospective study. BMC Ophthalmol 2021; 21:292. [PMID: 34340669 PMCID: PMC8330115 DOI: 10.1186/s12886-021-02048-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 07/09/2021] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND To compare the correction effect and optical quality after small-incision lenticule extraction (SMILE) and femtosecond laser assisted laser in situ keratomileusis (FS-LASIK) for high myopia. METHODS 51 high myopia eyes after SMILE and 49 high myopia eyes after FS-LASIK were enrolled and divided into two groups retrospectively. The OQAS and iTrace analyzer were used for optical quality inspection. Between the two groups the spherical equivalent (SE), astigmatism, uncorrected distant visual acuity (UDVA), strehl ratio (SR), modulation transfer function cutoff frequency (MTF cutoff), objective scatter index (OSI) and wavefront aberrations were analyzed and compared before surgery and at 1, 6 and 12 months after surgery. RESULTS After the operation: (1) SE and astigmatism declined and UDVA increased significantly in both groups, and UDVA was better after SMILE than FS-LASIK. (2) SR and MTF cutoff reduced and OSI increased significantly after SMILE and FS-LASIK. SR and MTF cutoff were significantly higher after SMILE than FS-LASIK. OSI was significantly lower after SMILE than FS-LASIK. (3) The total wavefront aberration, total low-order wavefront aberration, defocus and astigmatism aberration as well as trefoil aberration reduced significantly in both groups. The total high-order wavefront aberration increased significantly after FS-LASIK. The spherical and coma aberration increased significantly in both groups. The total high-order wavefront aberration and coma aberration at 1 month were higher after FS-LASIK than SMILE. CONCLUSION The optical quality descended after SMILE and FS-LASIK. SMILE was superior to FS-LASIK at the correction effect and optical quality for high myopia. The combination of OQAS and iTrace analyzer is a valuable complementary measurement in evaluating the optical quality after the refractive surgery. TRIAL REGISTRATION This is a retrospective study. This research was approved by the ethics committee of Xiangya Hospital and the IRB approval number is 201612074.
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Yu N, Ye Y, Chen P, Yang Y, Zhuang J, Yu K. Corneal Epithelial Thickness Changes Following SMILE for Myopia With High Astigmatism. J Refract Surg 2021; 37:224-230. [PMID: 34038662 DOI: 10.3928/1081597x-20210126-01] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
PURPOSE To evaluate the corneal epithelial thickness (CET) profile changes after small incision lenticule extraction (SMILE) surgery for myopic astigmatism correction of greater than 2.00 diopters (D). METHODS This prospective observational study included 40 eyes (23 patients) treated with SMILE for myopia with cylinders of -2.25 to -4.50 D. Along with standard ophthalmic examinations, CET maps with a diameter of 9 mm were measured by high-resolution spectral-domain optical coherence tomography preoperatively and postoperatively. Correlations between the degree of residual astigmatism and the difference in CET values between preoperative flat and steep meridians were analyzed. RESULTS The CET showed significant changes in the central (2 mm), paracentral (2 to 5 mm), midperipheral (5 to 7 mm), and peripheral (7 to 9 mm) zones 6 months after SMILE (P < .001). Among the regions, the CET in the paracentral zones displayed the largest increase (9.75%) with the highest average thickness (57.29 µm). Moreover, symmetrical regional epithelial thickening at the preoperative astigmatism axis was observed in the midperipheral zones. The difference in CET between preoperative flat and steep meridians in the mid-peripheral zones continuously increased from postoperative 1 day to 6 months. This difference was positively correlated with the residual cylinder errors at 6 months postoperatively (r = -0.334, P = .035). CONCLUSIONS The 9-mm diameter CET in eyes with high astigmatism significantly increased 6 months after SMILE. Additionally, the difference in CET between preoperative flat and steep meridians in midperipheral zones may be related to astigmatic undercorrection in SMILE. [J Refract Surg. 2021;37(4):224-230.].
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Abstract
PURPOSE Long-term evaluation of corneal epithelial thickness (ET) profile changes after photorefractive keratectomy (PRK) using Fourier-domain anterior segment optical coherence tomography. METHODS Three hundred twenty-six eyes of 163 patients were included in this prospective observational study. The corneal epithelial map was obtained across a 9-mm diameter area of the cornea before and up to 27 months after surgery. ET was assessed in 25 sectors and 4 annular zones (central 2 mm, paracentral 2-5 mm, midperipheral 5-7 mm, and peripheral 7-9 mm). RESULTS There was a significant reduction in mean ET in all zones 1 month after PRK. Subsequently, ET increased in all annular zones. The change in mean ET became stable in the midperipheral and peripheral zones at 3 to 6 months and in the central zone at 12 months, and it continued to increase in the paracentral zone even after 18 months after surgery. The ET was 3.40 μm and 4.05 μm in the central and paracentral zones at 6 months, respectively. Postoperative spherical equivalent changed significantly only from 1 to 3 months (P < 0.04). There was a significant correlation between postoperative spherical equivalent at month 1 and ET change in the paracentral and midperipheral zones (P < 0.027). CONCLUSIONS There is a significant reduction in ET 1 month after myopic PRK with a gradual thickening thereafter until it reaches stability at 12 months in the central zone. However, it continues to change even after 18 months in the paracentral zone. The greatest thickening is in the paracentral zone, followed by the central zone.
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Cao K, Liu L, Zhang T, Liu T, Bai J. Mutual comparative analysis: a new topography-guided custom ablation protocol referencing subjective refraction to modify corneal topographic data. EYE AND VISION 2020; 7:36. [PMID: 32656290 PMCID: PMC7339473 DOI: 10.1186/s40662-020-00201-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 06/15/2020] [Indexed: 12/25/2022]
Abstract
Background Several planning algorithms have been developed for topography-guided custom ablation treatment (T-CAT), but each has its own deficiencies. The purpose of this study is to demonstrate the potential of a novel mutual comparative analysis (MCA) informed by manifest refraction and corneal topographic data and the patient’s subjective perception in correcting ametropia. Methods This retrospective review included patients with significant preoperative differences in the power or axis of astigmatism according to the manifest refraction and corneal topographic data (power > 0.75 D and/or axis > 10°). T-CAT planning was designed using MCA. Follow-ups were conducted for at least 6 months. Results Seventy-nine patients (121 eyes) were included. The mean preoperative deviation in the astigmatic power and axis were 0.72 ± 0.43 D and 20.18 ± 23.68°, respectively. The average oculus residual astigmatism (ORA) was 0.81 ± 0.32 D (range: 0.08–1.66 D). Six months postoperatively, the mean spherical equivalent refraction was 0.04 ± 0.42 D, and the mean cylinder was − 0.27 ± 0.24 D. The mean efficacy and safety indices were 1.10 and 1.15, respectively. The uncorrected distance visual acuity in 92% of the eyes was the same or better than the corrected distance visual acuity. The angle of error was ±5° in 61% of eyes and ± 15° in 84% of eyes. Residual astigmatism was ≤0.5 D in 91% of eyes. Optical quality and photopic contrast sensitivity did not change significantly (p > 0.05), and the scotopic contrast sensitivity decreased at 3, 6, and 12 cpd (p < 0.05). The vertical coma and horizontal coma of the anterior corneal surface significantly decreased postoperatively but increased during follow-up. Conclusions The MCA demonstrated safety, efficacy, accuracy, predictability, and stability and can be used as a complementary and feasible method for T-CAT.
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Affiliation(s)
- Kaiwei Cao
- People's Liberation Army (PLA), No.1441 FengJu Ring Road, Jinniu District, Chengdu, 610081 China
| | - Lina Liu
- Chongqing vision institute, No. 77 Changjiang 2 Road, Yuzhong District, Chongqing, 400042 China
| | - Tao Zhang
- Chongqing vision institute, No. 77 Changjiang 2 Road, Yuzhong District, Chongqing, 400042 China
| | - Ting Liu
- Department of Ophthalmology, Daping Hospital and the Research Institute of Surgery of the Army Medical University of PLA, No. 10 Changjiangzhi Road, Yuzhong District, Chongqing, 400042 China
| | - Ji Bai
- Chongqing vision institute, No. 77 Changjiang 2 Road, Yuzhong District, Chongqing, 400042 China
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Myopia progression over a 4-year period after laser-assisted refractive surgery in patients in their 20s and 30s. Jpn J Ophthalmol 2020; 64:450-454. [PMID: 32519218 DOI: 10.1007/s10384-020-00751-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 02/22/2020] [Indexed: 10/24/2022]
Abstract
PURPOSE To investigate the increase in refractive error (RE) and axial length (AL) in myopia patients in their 20s and 30s after laser-assisted in situ keratomileusis (LASIK) or epipolis-LASIK (epi-LASIK). STUDY DESIGN Retrospective cohort study. METHODS This retrospective study involved 280 eyes of 140 myopia patients who underwent LASIK or epi-LASIK at the Baptist Eye Institute, Kyoto, Japan and who were followed for more than 5 years postoperatively. The patients were divided into 2 groups according to age: group A (age range, 20-29 years) and group B (age range, 30-39 years). In all patients, the RE and AL were measured at 1, 2, 3, 4, and 5 years postoperatively, and the 2 groups were compared in terms of each surgical method. RESULTS The patients' mean age at surgery was 30.6 ± 4.9 years. No significant difference was found between the 2 groups in terms of the preoperative mean spherical equivalent (SE) or AL. In the LASIK group, the mean changes in SE during the 4 years of study in groups A and B were + 0.054 ± 0.256 D and + 0.052 ± 0.327 D, respectively (P = .93, NS), and the postoperative increases in AL were 0.059 ± 0.134 mm and 0.027 ± 0.133 mm, respectively (P = .08, NS). In the epi-LASIK group, the mean change in SE during the 4 years of study in groups A and B were  -0.438 ± 0.207 D and -0.259 ± 0.454 D, respectively (P = .41, NS), and the postoperative increases in AL were 0.124 ± 0.141 mm and 0.094 ± 0.166 mm, respectively (P = .46, NS). CONCLUSION Our findings showed no significant difference in myopia progression in patients in their 20s and 30s during a 4-year period after either LASIK or epi-LASIK.
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One-year visual and astigmatic outcomes of keratoconus patients following sequential crosslinking and topography-guided surface ablation: the TOPOLINK study. J Cataract Refract Surg 2020; 46:507-516. [DOI: 10.1097/j.jcrs.0000000000000110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Zhang Y, Chen Y. A Randomized Comparative Study of Topography-Guided Versus Wavefront-Optimized FS-LASIK for Correcting Myopia and Myopic Astigmatism. J Refract Surg 2019; 35:575-582. [DOI: 10.3928/1081597x-20190819-01] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 08/19/2019] [Indexed: 11/20/2022]
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