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Tomas Loureiro,1 Sandra Rodrigues-Barros,1 Ana Rita Carreira,1 Filipe Gouveia-Moraes,1 Pedro Carreira,1 Ana Vide Escada,1 Paul Campos,1 Ines Machado,1 Nuno Campos,1 Renato Ambrosio Jr,2 Timothy J Archer,3 Dan Z Reinstein3 1Ophthalmology Department, Hospital Garcia de Orta, Almada, Portugal; 2Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil; 3London Vision Clinic, London, UKCorrespondence: Tomas Loureiro, Ophthalmology Department, Hospital Garcia de Orta, Avenida Torrado da Silva, Almada, 2805-267, Portugal, Tel +351 913 513 175, Email loureiro.tomas@gmail.comPurpose: To evaluate the changes on epithelial thickness before and after topical treatment in primary Sjögren syndrome-associated dry eye disease (SS-DED).Methods: This was a prospective study that included referred women with SS-DED and healthy age-matched controls. Corneal epithelial thickness was evaluated using high-definition anterior segment optical coherence tomography (Cirrus 5000 HD-OCT) in the baseline first consultation, and four weeks after treatment with preservative free 1mg/1mL sodium hyaluronate. Schirmer test 1 (ST1), tear break-up time (TBUT), tear meniscus height (TMH), SICCA Ocular Surface Score (SICCA OSS) and Ocular Surface Disease Index (OSDI) were evaluated. Statistical significance was defined as p-value < 0.05.Results: The study included 40 eyes, 20 with SS-DED and 20 controls. At baseline, SS-DED patients had lower ST1 (11.1 ± 2.2mm vs 14.1 ± 3.1mm, p< 0.01), faster TBUT (9.1 ± 1.8s vs 13.2 ± 1.1s, p< 0.01) and lower TMH (211.2 ± 68.4 μm vs 217.2 ± 60.1μm; p< 0.01) than the control group, whereas SICCA OSS and OSDI were higher (p< 0.01). The superior epithelium was thinner in SS-DED group (41.1 ± 3.2 μm vs 43.1± 2.3 μm, p< 0.01). After treatment, ST1, TBUT, TMH, SICCA OSS, and OSDI improved (p< 0.01), and superior epithelium thickened (p< 0.01) in the SS-DED group.Conclusion: Treatment with sodium hyaluronate improved ST1, TBUT, TMH, SICCA-OSS, and OSDI score. Superior epithelium tends to be thinner in SS-DED but becomes thicker with treatment. Our results seem to illustrate the morphological changes in the corneal epithelium in DED, which could be further recognized as a clinical biomarker of SS-DED.Keywords: dry eye disease, Sjogren’s syndrome, epithelial thickness, AS-OCT

Tomás Loureiro,1 Sandra Rodrigues-Barros,1 Ana Rita Carreira,1 Filipe Gouveia-Moraes,1 Pedro Carreira,1 Ana Vide Escada,1 Paul Campos,1 Inês Machado,1 Nuno Campos,1 Timothy J Archer,2 Dan Z Reinstein,2 Renato Ambrósio Jr3 1Ophthalmology Department, Hospital Garcia de Orta, Almada, Portugal; 2London Vision Clinic, London, UK; 3Federal University of the State of Rio de Janeiro, Rio de Janeiro, BrazilCorrespondence: Tomás Loureiro, Ophthalmology Department, Hospital Garcia de Orta, Avenida Torrado da Silva, Almada, 2805-267, Portugal, Tel +35 1 913 513 175, Email loureiro.tomas@gmail.comPurpose: To evaluate the effect of eye rubbing on the epithelial thickness profile in tomographically normal corneas by AS-OCT and to compare right and left eyes in right-handed children.Methods: Thirty right-handed boys (mean age 11.2 years) with ocular allergy and history of eye rubbing were evaluated using Scheimpflug (Pentacam HR, Oculus Wetzlar, Germany) and anterior segment optical coherence tomography. Epithelial thickness (ET) and full corneal thickness (CT) parameters were compared between right and left eyes with a non-parametric Mann–Whitney test. A p-value lower than 0.05 was considered for statistical significance.Results: No eyes had topometric nor tomographic criteria for keratoconus. The min-max ET was lower in right eyes (− 2.8 μm vs − 3.5; p = 0.02). The difference between inferior and superior (I-S) octants was lower in right eyes (1.1 μm vs 1.9 μm; p = 0.03) as a result of inferotemporal thinning. The highest ET difference was registered between nasal and temporal octants and was more pronounced in the right eyes (2 μm vs 3.1 μm; p < 0.001).Conclusion: AS-OCT analyses reveal different epithelial thickness patterns between the eyes in young atopic patients, likely eye rubbers. Inferior and temporal epithelial thickness seem to be more affected by thinning in the eye on the side of the dominant hand.Keywords: eye rubbing, keratoconus, epithelial thickness, AS-OCT, pediatrics

Dan Z Reinstein,1– 4 Ryan S Vida,1 Timothy J Archer1 1London Vision Clinic, London, UK; 2Columbia University Medical Center, New York, NY, USA; 3Sorbonne Université, Paris, France; 4Biomedical Science Research Institute, Ulster University, Coleraine, UKCorrespondence: Dan Z ReinsteinLondon Vision Clinic, 138 Harley Street, London, W1G 7LA, UKTel +44 207 224 1005Fax +44 207 224 1055Email dzr@londonvisionclinic.comPurpose: Report the outcomes of the implantable collamer lens (ICL) in myopic astigmatism using very high-frequency (VHF) digital ultrasound sizing.Methods: Analysis of 42 consecutive ICL procedures using EVO and EVO+ (Visian V4c) lenses (STAAR Surgical) was done. ICL size was chosen using the ultrasound-based Kojima Formula with Insight 100 VHF digital ultrasound (VHFDU). Standard visual outcomes analysis was performed using 3-month data, also including contrast sensitivity, refractive and corneal vector analysis, and ECC. Postoperative lens position was evaluated using VHF digital ultrasound.Results: Attempted SEQ was − 10.83± 3.39D (− 4.40 to − 16.98D). Cylinder was − 1.46± 1.15D (0.00 to − 4.25D). One-year follow-up was available in 86% of the eyes and 3 months in 96%. Postoperative UDVA was 20/20 or better in 89% of the eyes, relative to 71% preoperatively. Postoperative SEQ refraction was ± 0.50 D in 74% and ± 1.00 D in 98% of the eyes. There was a gain of one line of CDVA in 43% of the eyes, 2 or more lines in 10% of the eyes, while there was a one line loss in 7% and no eyes lost 2 or more lines. The vector mean for the corneal SIA was 0.24 D Ax 100. Contrast sensitivity showed a statistically significant increase with a mean of 0.14 log units at 6, 12, and 18 cycles per degree (P< 0.01). The mean change in ECC was − 153± 353 cells/mm2. Lens vault was 506± 233 μm (114– 924 μm). Footplate insertion was in zonular position in 48.3%, ciliary body in 49.2%, and sulcus in 2.5% of locations.Conclusion: ICL implantation resulted in high safety and efficacy but with an implantation vault range that ideally would be improved upon. VHF digital ultrasound of the lens footplate and posterior anatomical relations may provide essential information for evaluating postoperative vault outliers.Keywords: implantable collamer lens, ICL, phakic IOL, footplate, VHF digital ultrasound

Latest devices improve keratoconus screening, IOP measurement, corneal topography and more. [ABSTRACT FROM AUTHOR]

Purpose: Propose new terminology and evaluate the effectiveness of Therapeutic Refractive Vitrectomy (TRV) for selective removal of vitreous floaters and opacities (VFO) utilizing Standardized Kinetic Anatomical Functional Testing of VFO (SK VFO Test) and new ultra widefield (UWF) OCT imaging techniques., Methods: Retrospective analysis. Twenty eyes underwent TRV for symptomatic VFO. Pre-/post-TRV assessments: SK-VFO Test, including straylight measurements (HD Analyzer, Light Disturbance Analyzer, C-Quant) alongside non-contact imaging including a new UWF OCT to evaluate changes in vitreous anatomical and optical properties., Results: Post-TRV evaluations indicated objective changes in vitreous optical properties and subjective measures. Reduced straylight measurements: HDA 22%, LDA 54.4% (p=0.013), and C-Quant 7.8% (p=0.034). Patient reported outcomes statistically significantly improved (p=0.022). Corrected distance visual acuity (CDVA) changes were marginal. New UWF 26 mm with a 12 mm imaging window OCT facilitated detailed vitreous imaging, confirming status of posterior vitreous detachment (PVD) (100%). Post-TRV UWF and OCT imaging demonstrated restoration of vitreous clarity, confirmed presence of residual cortical vitreous and absence of new PVDs., Conclusion: TRV is a significant contribution for therapeutic refractive surgery as a safe and effective approach to enhancing visual quality, correcting refractive and opaque vitreous anomalies. Improvement in CDVA was minimal representing limited effectiveness as a measure of comprehensive visual function. Improvements in objective straylight measures and imaging are in alignment with subjective symptom improvements post-TRV. This underscores the utility and value of new holistic evaluation methods beyond traditional metrics to assess the impact of TRV on visual function and quality of life., Competing Interests: Competing interests: The authors declared no potential conflicts of interest with respect to the research, authorship or publication of this article.

Aims: To develop a generative adversarial network (GAN) capable of generating realistic high-resolution anterior segment optical coherence tomography (AS-OCT) images., Methods: This study included 142 628 AS-OCT B-scans from the American University of Beirut Medical Center. The Style and WAvelet based GAN architecture was trained to generate realistic AS-OCT images and was evaluated through the Fréchet Inception Distance (FID) Score and a blinded assessment by three refractive surgeons who were asked to distinguish between real and generated images. To assess the suitability of the generated images for machine learning tasks, a convolutional neural network (CNN) was trained using a dataset of real and generated images over a classification task. The generated AS-OCT images were then upsampled using an enhanced super-resolution GAN (ESRGAN) to achieve high resolution., Results: The generated images exhibited visual and quantitative similarity to real AS-OCT images. Quantitative similarity assessed using FID scored an average of 6.32. Surgeons scored 51.7% in identifying real versus generated images which was not significantly better than chance (p value >0.3). The CNN accuracy improved from 78% to 100% when synthetic images were added to the dataset. The ESRGAN upsampled images were objectively more realistic and accurate compared with traditional upsampling techniques by scoring a lower Learned Perceptual Image Patch Similarity of 0.0905 compared with 0.4244 of bicubic interpolation., Conclusions: This study successfully developed and leveraged GANs capable of generating high-definition synthetic AS-OCT images that are realistic and suitable for machine learning and image analysis tasks., Competing Interests: Competing interests: DZR is a consultant for Carl Zeiss Meditec (Carl Zeiss Meditec AG, Jena, Germany). DZR is also a consultant for CSO Italia (Florence, Italy) and has a proprietary interest in the Artemis technology (ArcScan Inc, Golden, Colorado) through patents administered by the Cornell Center for Technology Enterprise and Commercialization (CCTEC), Ithaca, New York. The remaining authors have no proprietary or financial interest in the materials presented herein., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To investigate the efficacy of incorporating Generative Adversarial Network (GAN) and synthetic images in enhancing the performance of a convolutional neural network (CNN) for automated estimation of Implantable Collamer Lens (ICL) vault using anterior segment optical coherence tomography (AS-OCT)., Methods: This study was a retrospective evaluation using synthetic data and real patient images in a deep learning framework. Synthetic ICL AS-OCT scans were generated using GANs and a secondary image editing algorithm, creating approximately 100,000 synthetic images. These were used alongside real patient scans to train a CNN for estimating ICL vault distance. The model's performance was evaluated using statistical metrics such as mean absolute percentage error (MAPE), mean absolute error (MAE), root mean squared error (RMSE), and coefficient of determination ( R 2 ) for the estimation of ICL vault distance., Results: The study analyzed 4,557 AS-OCT B-scans from 138 eyes of 103 patients for training. An independent, retrospectively collected dataset of 2,454 AS-OCT images from 88 eyes of 56 patients, used prospectively for evaluation, served as the test set. When trained solely on real images, the CNN achieved a MAPE of 15.31%, MAE of 44.68 µm, and RMSE of 63.3 µm. However, with the inclusion of GAN-generated and algorithmically edited synthetic images, the performance significantly improved, achieving a MAPE of 8.09%, MAE of 24.83 µm, and RMSE of 32.26 µm. The R 2 value was +0.98, indicating a strong positive correlation between actual and predicted ICL vault distances ( P < .01). No statistically significant difference was observed between measured and predicted vault values ( P = .58)., Conclusions: The integration of GAN-generated and edited synthetic images substantially enhanced ICL vault estimation, demonstrating the efficacy of GANs and synthetic data in enhancing OCT image analysis accuracy. This model not only shows potential for assisting postoperative ICL evaluations, but also for improving OCT automation when data paucity is an issue. [ J Refract Surg . 2024;40(4):e199-e207.] .

Purpose of Review: Posterior chamber phakic intraocular lenses (pIOLs) are increasing in popularity as a viable alternative to laser refractive surgery. The purpose of this review is to evaluate the recent updates to pIOLs and to assess the advancements and safety of the procedure., Recent Findings: Accurate lens sizing is the key determinant to suitable vault prediction, advancements to sizing formulae including the use of very high frequency (VHF) digital ultrasound and the application of artificial intelligence and machine learning has led to improved vault prediction and safety. The introduction of the central aquaport has been shown to reduce the formation of cataract and is now adopted in most myopic pIOLs. Recently published studies have demonstrated that pIOLs have an excellent safety profile with no increased risk of retinal detachment or endothelial cell loss. Advancements have led to the introduction of extended depth of focus pIOLs for the correction of presbyopia, further research is required to evaluate the efficacy of new lens designs., Summary: pIOL surgery is experiencing traction with improved lens design and increased lenses choices such as larger optical zone and presbyopic options. Accuracy of implantable collamer lens sizing is paramount to the safety and clinical outcomes, greater predictability is likely to encourage more posterior chamber pIOL users due to fewer sizing related complications., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: To evaluate the outcome of sequential customized therapeutic keratectomy (SCTK) in reducing higher order aberrations (HOAs) and improving quality of vision in highly aberrated corneas consequent to previous radial keratotomy (RK)., Methods: A retrospective review of patients undergoing SCTK treatment from January 2012 to October 2020 was conducted in the Eye Center, Humanitas Clinical and Research Center (Rozzano, Italy). Indications for treatment in patients who had RK were significantly and/or progressively reduced corrected distance visual acuity (CDVA) combined with visual symptoms critically affecting quality of life. Preoperative and postoperative CDVA, corneal topography and aberrometry, Scheimpflug tomography, and anterior segment optical coherence tomography were registered., Results: Thirty-four patients who underwent RK a mean of 26.62 ± 7.10 years before SCTK treatment were included. SCTK induced a significant improvement of CDVA from 0.44 ± 0.82 logMAR preoperatively to 0.15 ± 0.64 logMAR postoperatively ( P < .001). No patient experienced worsening of CDVA, whereas 8 patients (23,50%) gained one line and 23 patients (67.65%) gained two lines or more. A significant decrease in corneal coma, trefoil, and spherical aberrations was also noted ( P = .003, .003, and .004, respectively)., Conclusions: SCTK proved to be a safe and effective option to treat highly aberrated eyes following RK. The authors suggest the use of SCTK as a first-line approach for the treatment of HOAs after RK and avoiding more invasive procedures such as corneal transplantation or intraocular lens implantation. [ J Refract Surg . 2023;39(12):808-816.] .

Purpose: To develop and validate a deep learning neural network for automated measurement of implantable collamer lens (ICL) vault using anterior segment optical coherence tomography (AS-OCT)., Design: Cross-sectional retrospective study., Methods: A total of 2647 AS-OCT scans were used from 139 eyes of 82 subjects who underwent ICL surgery in 3 different centers. Using transfer learning, a deep learning network was trained and validated for estimating the ICL vault on OCT. A trained operator separately reviewed all OCT scans and measured the central vault using a built-in caliper tool. The model was then separately tested on 191 scans. A Bland-Altman plot was constructed and the mean absolute percentage error (MAPE), mean absolute error (MAE), root mean squared error (RMSE), Pearson correlation coefficient (r), and determination coefficient (R 2 ) were calculated to evaluate the strength and validity of the model., Results: On the test set, the model achieved a MAPE of 3.42%, an MAE of 15.82 µm, a RMSE of 18.85 µm, a Pearson correlation coefficient r of +0.98 (P < .00001), and a coefficient of determination R 2 of +0.96. There was no significant difference between the vaults of the test set labeled by the technician vs those estimated by the model: 478 ± 95 µm vs 475 ± 97 µm, respectively, P = .064)., Conclusions: Using transfer learning, our deep learning neural network was able to accurately compute the ICL vault from AS-OCT scans, overcoming the limitations of an imbalanced data set and limited training data. Such an algorithm can assist the postoperative assessment in ICL surgery., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Purpose: To optimize artificial intelligence (AI) algorithms to integrate Scheimpflug-based corneal tomography and biomechanics to enhance ectasia detection., Design: Multicenter cross-sectional case-control retrospective study., Methods: A total of 3886 unoperated eyes from 3412 patients had Pentacam and Corvis ST (Oculus Optikgeräte GmbH) examinations. The database included 1 eye randomly selected from 1680 normal patients (N) and from 1181 "bilateral" keratoconus (KC) patients, along with 551 normal topography eyes from patients with very asymmetric ectasia (VAE-NT), and their 474 unoperated ectatic (VAE-E) eyes. The current TBIv1 (tomographic-biomechanical index) was tested, and an optimized AI algorithm was developed for augmenting accuracy., Results: The area under the receiver operating characteristic curve (AUC) of the TBIv1 for discriminating clinical ectasia (KC and VAE-E) was 0.999 (98.5% sensitivity; 98.6% specificity [cutoff: 0.5]), and for VAE-NT, 0.899 (76% sensitivity; 89.1% specificity [cutoff: 0.29]). A novel random forest algorithm (TBIv2), developed with 18 features in 156 trees using 10-fold cross-validation, had a significantly higher AUC (0.945; DeLong, P < .0001) for detecting VAE-NT (84.4% sensitivity and 90.1% specificity; cutoff: 0.43; DeLong, P < .0001) and a similar AUC for clinical ectasia (0.999; DeLong, P = .818; 98.7% sensitivity; 99.2% specificity [cutoff: 0.8]). Considering all cases, the TBIv2 had a higher AUC (0.985) than TBIv1 (0.974; DeLong, P < .0001)., Conclusions: AI optimization to integrate Scheimpflug-based corneal tomography and biomechanical assessments augments accuracy for ectasia detection, characterizing ectasia susceptibility in the diverse VAE-NT group. Some patients with VAE may have true unilateral ectasia. Machine learning considering additional data, including epithelial thickness or other parameters from multimodal refractive imaging, will continuously enhance accuracy. NOTE: Publication of this article is sponsored by the American Ophthalmological Society., (Copyright © 2022. Published by Elsevier Inc.)

Purpose: To assess repeatability and agreement of corneal epithelial thickness mapping in eyes with keratoconus using three optical coherence tomography (OCT) devices featuring different technologies: spectral-domain (SD) OCT combined with Placido disk corneal topography (MS-39), swept-source OCT (Anterion), and SD-OCT (Avanti)., Methods: Three consecutive measurements were acquired with the three devices in 60 eyes with keratoconus. The mean epithelial thickness was calculated in the central 2-mm zone and in 2- to 5-mm and 5- to 7-mm diameter rings. The repeatability was calculated using pooled within-subject standard deviation (S w ). The agreement was assessed by paired t tests and Bland-Altman plots., Results: The repeatability (Sw) of the epithelial thickness for the central 2-mm zone was 0.91, 0.71, and 0.93 μm for the MS-39, Anterion, and Avanti, respectively. All thicknesses with the MS-39 were greater than those of the Anterion and Avanti, with mean differences of 4.11 ± 1.34 μm ( P < .001) and 0.52 ± 1.30 μm ( P = .003), respectively. The 95% limits of agreement were 1.484 to 6.736 μm for the MS-39 and Anterion, -3.068 to 2.028 μm for the Avanti and MS-39, and 1.258 to 5.922 μm for for the Avanti and Anterion., Conclusions: Epithelial thickness mapping results were most repeatable with the Anterion, followed by the MS-39 and Avanti. The MS-39 gave the thickest values, followed by the Avanti and Anterion. The differences were significant, making the devices not interchangeable for epithelial thickness mapping in eyes with keratoconus. [ J Refract Surg . 2023;39(7):474-480.] .

Purpose: To evaluate and compare the incidence of transient light sensitivity syndrome (TLSS) after myopic laser in situ keratomileusis (LASIK), hyperopic LASIK, and myopic small incision lenticule extraction (SMILE)., Methods: A retrospective analysis was performed of consecutive LASIK and myopic SMILE cases, performed with the VisuMax femtosecond laser and MEL 80 or MEL 90 excimer laser (both Carl Zeiss Meditec AG) between January 2010 and February 2021 at London Vision Clinic, London, United Kingdom. A chart review was performed to find cases of clinically significant TLSS, identified as patients prescribed anti-inflammatory medications between 2 weeks and 6 months after surgery to manage photophobia. The incidence of TLSS was calculated for three groups: myopic SMILE, myopic LASIK, and hyperopic LASIK. The incidence of TLSS was then calculated for three subgroups within each treatment type based on spherical equivalent refraction treated. For myopic SMILE and myopic LASIK, it was 0.00 to -4.00 diopters (D) (low), -4.01 to -8.00 D (moderate), and -8.01 to -14.00 D (high). For hyperopic LASIK, it was 0.00 to +2.00 D (low), +2.01 to +4.00 D (moderate), and +4.01 to +6.50 D (high)., Results: The range of treatment for myopia was similar between the LASIK and SMILE groups. The incidence of TLSS was 1.2% for the myopic SMILE group, 5.3% for the myopic LASIK group, and 9.0% for the hyperopic LASIK group. The difference was statistically significant between all groups ( P < .001). For myopic SMILE, the incidence of TLSS was independent of spherical equivalent refraction for low (1.4%), moderate (1.0%), and high (1.1%) myopia ( P > .05). Similarly, for hyperopic LASIK, the incidence was similar for low (9.4%), moderate (8.7%), and high (8.7%) hyperopia ( P > .05). In contrast, for myopic LASIK, the incidence of TLSS was "dose-dependent" on refractive error treated, with an incidence of 4.7% for low, 5.8% for moderate, and 8.1% for high myopia ( P < .001)., Conclusions: The incidence of TLSS was higher after myopic LASIK than after myopic SMILE, higher after hyperopic than myopic LASIK, and "dose-dependent" for myopic LASIK but did not vary by correction in myopic SMILE. This is the first report describing the phenomenon of late TLSS occurring between 8 weeks and 6 months after surgery, [ J Refract Surg . 2023:39(6):366-373.] .

Purpose: To describe a standardized three-stage flap replacement protocol and report the incidence of microfolds after femtosecond laser-assisted laser in situ keratomileusis (LASIK) surgery., Methods: A retrospective analysis of 14,374 consecutive LASIK procedures with the VisuMax femtosecond laser (Carl Zeiss Meditec) by two surgeons was conducted. As per the standardized procedure, all eyes underwent the three-stage flap replacement protocol consisting of controlled standardized minimal irrigation and flap repositioning after ablation, followed by fluorescein-controlled slit-lamp adjustments and slit-lamp adjustments on day 1 (if required). Microfold incidence was recorded at all subsequent visits and recorded by independent observers classified using a standardized 6-point grading system including whether they were refractively or visually significant., Results: Flap thickness used was 80 to 89 µm (7.2%), 90 to 99 µm (51.7%), 100 to 109 µm (17.8%), and 110 to 130 µm (23.2%). Slit-lamp adjustment at day 1 was performed in 956 eyes (6.77%), with the highest incidence in 80 to 89 µm flaps (27.6%). A flap slip occurred in 23 eyes (0.16%) and was managed at the slit lamp for 21 eyes and in the operating room for 2 eyes. At 3 months after surgery, trace microfolds were present in 158 eyes (1.10%), grade 1 in 26 eyes (0.184%), and grade 2 in 2 eyes (0.016%). Grade 1 microfold incidence per flap thickness group was 39.1% for 80 to 89 µm, 30.4% for 90 to 99 µm, 13% for 100 to 109 µm, and 17.4% for 110 to 130 µm. No eyes required a flap lift for microfolds in the operating room. Multivariate regression analysis found microfold incidence to be higher for thinner flaps, higher correction, and larger optical zone., Conclusions: The three-stage protocol for flap positioning and management resulted in a low incidence of clinically visible microfolds and no visually significant microfolds. Day 1 slit-lamp adjustment was required more frequently in ultra-thin 80 to 89 µm flaps. [ J Refract Surg . 2023;39(6):388-396.] .

Purpose: To report the first refractive and visual outcomes of small incision lenticule extraction (SMILE) using the VISUMAX 800 femtosecond laser (Carl Zeiss Meditec AG)., Methods: This was a retrospective analysis of consecutive eyes treated by SMILE using the VISUMAX 800 femtosecond laser at London Vision Clinic, EuroEyes Group, London, United Kingdom. Inclusion criteria were patients aged younger than 45 years, a corrected distance visual acuity (CDVA) of 20/20 or better, and the 3-month postoperative timepoint data being available for analysis. Standard outcomes analysis and vector analysis by the Alpins method were performed., Results: During the study period, 128 eyes of 66 consecutive patients were treated. Three-month data were available for 118 eyes (92%), and 10 eyes (8%) were lost to follow-up. The mean attempted spherical equivalent refraction (SEQ) was -4.65 ± 1.91 diopters (D) (range: -1.90 to -10.05 D) and the mean cylinder was -0.98 ± 0.78 D (range: 0.00 to -4.00 D). The mean age was 30 ± 5 years (range: 20 to 43 years), with 54% women and 46% men. Postoperative SEQ was within ±0.50 D in 86% and ±1.00 D in 100% of eyes. Uncorrected distance visual acuity was 20/20 or better in 91% of eyes. One line of CDVA was lost in 8% of eyes, and no eyes lost two or more lines. There was a small but statistically significant increase in contrast sensitivity at 3, 6, 12, and 18 cpd., Conclusions: Early outcomes data for SMILE with the second generation VISUMAX 800 femtosecond laser demonstrated an effective and safe option equivalent to published first generation VisuMax outcomes for the treatment myopia and astigmatism. [ J Refract Surg . 2023;39(5):294-301.] .

Objective: To introduce VFO and SK VFO Test: new, more representative terminology for symptoms of vitreous floaters/opacities (VFO) and new standardized kinetic (SK) anatomical-functional assessment., Materials and Methods: Eight eyes underwent before-after limited vitrectomy (LV): best-corrected visual acuity, low-luminance visual acuity, Minnesota Low Vision Reading Chart near visual acuity in logMAR, contrast sensitivity function (CV1000E), and straylight measurements (SM) (HDA/LDA/C-Quant). SK infrared confocal scanning laser ophthalmoscopy (SK IRcSLO) and swept-source widefield optical coherence tomography (SS-WF-OCT) identified VFO and posterior vitreous detachment (PVD). SK IRcSLO was performed with gaze directed towards the extreme superior, inferior, and lateral directions., Results: Anatomical-functional results after LV improved in 7 eyes (87.5%): objective scatter index (27.34%), disturbance index (47.97%) and C-Quant Log units (2.26%). Pre-LV SK IRcSLO and SS-WFOCT imaging identified dynamic well-defined VFO and PVD status (100%). A residual asymptomatic anterior cortical vitreous-induced shadowing ripple effect was detected post-LV., Conclusions: This is the first objective-standardized test accounting for VFO kinesis and intermittent effect. There is potential for personalizing treatment and establishing best candidates for laser or surgery. [ Ophthalmic Surg Lasers Imaging Retina 2023;54:306-315.] .

Purpose: To report the outcomes of PRESBYOND Laser Blended Vision LASIK (Carl Zeiss Meditec AG) in presbyopic commercial and military pilots requiring Class 1 aeromedical certification., Methods: This was a retrospective study of 23 consecutive pilots who underwent PRESBYOND Laser Blended Vision LASIK. Postoperative visits were conducted at 1 day and 1, 3, and 12 months. Standard outcomes analysis was performed using the data at 12 months. Objective quality of vision measures including mesopic contrast sensitivity (CSV-1000; VectorVision), Ocular Scatter Index (HD Analyzer; Keeler), and straylight (C-Quant; Oculus Optikgeräte GmbH) were determined before and 3 months after surgery. A questionnaire to assess the functional vision of pilots before and after surgery was derived to record subjective outcomes., Results: Of the 23 pilots treated, data were available at 12 months for 22 pilots (95.7%) and at 3 months for 1 pilot (4.3%). Median age was 55 years (range: 42 to 65 years). At 12 months, binocular uncorrected distance visual acuity was 20/20 or better in 100% and 20/16 or better in 52% of pilots. Binocular uncorrected intermediate visual acuity was J3 in 73%, J5 in 95%, and J10 in 100% of pilots. Binocular uncorrected near visual acuity was J1 or better in 78% and J2 or better in 100% of pilots. Mean postoperative spherical equivalent refraction relative to the target was -0.04 ± 0.34 diopters (D) (range: -0.63 to +0.63 D), with 93% within ±0.50 D. There was a statistically significant increase in contrast sensitivity at 3, 6, 12, and 18 cpd. C-Quant straylight was 1.07 ± 0.16 before surgery and 1.06 ± 0.16 at 1 to 3 months after surgery ( P = .705). All pilots achieved Class 1 medical certification from the United Kingdom Civil Aviation Authority and resumed flying. All pilots reported improved functionality compared to the previous vision correction method., Conclusions: PRESBYOND Laser Blended Vision LASIK enabled presbyopic commercial pilots to continue to fly without the need for glasses. With consideration of the visually challenging cockpit environment, PRESBYOND Laser Blended Vision LASIK provides clear continuous vision for tasks at near, intermediate, and far distance. Class 1 pilots reported a subjective improvement in visual tasks and comfort following surgery. [ J Refract Surg . 2023;39(1):6-14.] .

Purpose: To investigate the safety and effectiveness of small incision lenticule extraction (SMILE) in patients who have hyperopia with or without astigmatism., Methods: This was a prospective multicenter trial including 374 eyes of 199 patients treated by SMILE for hyperopia using the VisuMax femtosecond laser (Carl Zeiss Meditec AG). Inclusion criteria were sphere up to +6.00 diopters (D), cylinder up to 5.00 D, and maximum hyperopic meridian up to +7.00 D, with preoperative corrected distance visual acuity (CDVA) of 20/25 or better. The optical zone was 6.3 mm with a transition zone of 2 mm. The minimum lenticule thickness was set at 25 µm in the center and at 10 µm at the edge. Patients were examined at 1 day, 1 week, and 1, 3, 6, 9, and 12 months after surgery. Standard refractive surgery outcomes analysis was performed., Results: The preoperative spherical equivalent was +3.20 ± 1.48 D (range: +0.25 to +6.50 D). At the 12-month follow-up visit, 81% of eyes treated were within ±0.50 D and 93% of eyes were within ±1.00 D of intended correction. A total of 1.2% of eyes lost two or more lines of CDVA at the 12-month follow-up visit, and 83% were at least 20/20, corresponding to a safety index of 1.005 at 12 months. Of the 219 eyes with plano target, 68.8% had an uncorrected distance visual acuity of 20/20 or better and 88% were at least 20/25 uncorrected at 12 months. There were no statistically significant changes in contrast sensitivity., Conclusions: SMILE was found to be an effective treatment method for the correction of compound hyperopic astigmatism, demonstrating a high level of efficacy, predictability, safety, and stability. [ J Refract Surg . 2022;38(12):760-769.] .

Purpose: To study the objective change in light disturbance around a glare source using the Light Disturbance Analyzer (LDA) (Binarytarget Lda) and correlate this with the validated subjective quality of vision (QoV) questionnaire in small incision lenticule extraction (SMILE) for high compound myopic astigmatism., Methods: This was a prospective study recruiting 114 patients undergoing SMILE with attempted spherical equivalent refraction (SEQ) correction from -9.00 to -13.00 diopters (D), and cylinder up to 5.00 D. The LDA was used before and 3 and 12 months after surgery to evaluate the Light Disturbance Area, Light Disturbance Index, Best Fit Circle Radius, and Best Fit Circle Irregularity. Patients completed the Rasch-validated QoV questionnaire before and 12 months after surgery. Correlation analysis was performed between the LDA parameters and the QoV frequency, severity, and bothersomeness for halos and starbursts., Results: At 12 months, there was a non-statistically signifcant change of 11.9% for Light Disturbance Area and Light Disturbance Index and 6.5% for Best Fit Circle Radius. There was an increase of 81.9% for Best Fit Circle Irregularity ( P = .017). Light Disturbance Area, Light Disturbance Index, and Best Fit Circle Radius correlated with bothersomeness for QoV halos, and with frequency, severity and bothersomeness for QoV star-bursts (P < .05), albeit with a low correlation coefficient ( R 2 < 0.13). There was no correlation between increase in Best Fit Circle Irregularity and the halo and starburst scores from the QoV questionnaire., Conclusions: LDA Best Fit Circle Irregularity was found to increase following high myopic SMILE. Other LDA parameters appeared to increase, but a much larger sample would be required to find statistical significance. The change in LDA parameters was only weakly correlated with QoV halo and starburst metrics, representing the wide variation in inter-subject perception. [ J Refract Surg . 2022;38(11):725-732.] .

Purpose: To analyze the optical consequences of epithelial remodeling in irregular corneas and their impact on the choice of different surface ablation techniques., Methods: Anterior corneal and stromal surface topographies and epithelial thickness maps were analyzed in 24 eyes with irregular corneal optics. On two of the eyes, four different surface ablation techniques were simulated: (1) conventional anterior topography-guided photorefractive keratectomy (PRK), (2) transepithelial phototherapeutic keratectomy (PTK), (3) transepithelial anterior topography-guided PRK, and (4) stromal topography-guided PRK., Results: Stromal surface topographies showed higher keratometric values, astigmatism, asphericity, and corneal higher order aberrations compared to topographies of anterior corneas covered by epithelium. Transepithelial anterior topography-guided PRK and stromal topography-guided PRK both resulted in regularized stromal surface, transepithelial PTK achieved partial regularization corresponding to the smoothing effect of the epithelial remodeling, and conventional anterior topography-guided PRK delivered after epithelial removal resulted in residual stromal surface irregularities., Conclusions: The difference in optical landscapes between the stromal and anterior surfaces in irregular corneas will represent a source of error when anterior topography-guided treatments are delivered on the deepithelialized stroma, as in conventional PRK. In contrast, anterior topography-guided ablations performed as transepithelial PRK and stromal topography-guided PRK delivered after epithelial removal address the full stromal irregularity, whereas transepithelial PTK alone may be used when topography-guided treatments are not possible. The authors conclude topography-guided PRK of irregular corneas should lead to significantly improved regularization only if it includes the effect of epithelial remodeling. [ J Refract Surg . 2022;38(8):529-537.] .

Purpose: To evaluate the outcomes of small incision lenticule extraction (SMILE) for myopia in a large population of young adults., Methods: In this retrospective case series, the patient population consisted of the first 4,138 consecutive SMILE treatments using the VisuMax femtosecond laser (Carl Zeiss Meditec) between 2012 and 2018 at the London Vision Clinic. Inclusion criteria were myopic spherical equivalent up to -9.00 diopters (D), cylinder up to 6.00 D, corrected distance visual acuity of 20/20 or better, age younger than 40 years, and follow-up of 12 months. Outcomes analysis was performed using the Standard Graphs for Reporting Refractive Surgery., Results: Data were available at 12 months in 3,722 eyes (90%), and 416 eyes (10%) were lost to follow-up. Mean attempted spherical equivalent refraction (SEQ) was -4.61 ± 1.84 D (range: -1.12 to -9.00 D). Mean cylinder was -0.78 ± 0.66 D (range: 0.00 to -6.00 D). Postoperatively, the mean SEQ relative to target was -0.13 ± 0.30 D (range: -1.35 to +1.25 D) and was within ±0.50 D in 88.1% and ±1.00 D in 99.6% of eyes. Uncorrected distance visual acuity was 20/20 or better in 95.4% of eyes and 20/25 or better in 98.7% of eyes. One line of CDVA was lost in 3.0% of eyes, and 0.08% (n = 3) lost two or more lines of CDVA, for which CDVA was restored following phototherapeutic keratectomy treatment. There was a statistically significant improvement of 0.05, 0.06, 0.07, and 0.07 log units for contrast sensitivity at 3, 6, 12, and 18 cycles per degree, respectively ( P < .001)., Conclusions: SMILE achieved excellent outcomes for myopia up to -9.00 D with cylinder up to -5.50 D for a large population in patients without presbyopia. [ J Refract Surg . 2022;38(8):488-496.] .

In this review, we discuss the applications of epithelial thickness mapping in corneal refractive surgery. The review describes that the epithelial thickness profile is nonuniform in the normal eye, being thinner superiorly than inferiorly and thinner temporally than nasally. It is postulated that this is due to the eyelid forces and blinking action on the superior cornea. Changes in the epithelial thickness profile have been found to be highly predictable, responding to compensate for changes in the stromal curvature gradient, using the eyelid as an outer template. This leads to characteristic changes in the epithelial thickness profile that can be used for early screening in keratoconus, postoperative monitoring for early signs of corneal ectasia, and for determining whether further steepening can be performed without the risk of apical syndrome following primary hyperopic treatment. Compensatory epithelial thickness changes are also a critical part of diagnosis in irregular astigmatism as these partially mask the stromal surface irregularities. The epithelial thickness map can then be used to plan a trans-epithelial photorefractive keratectomy treatment for cases of irregularly irregular astigmatism., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 Saudi Journal of Ophthalmology.)

Purpose: To report subjective and objective quality of vision (QoV) results for high myopic small incision lenticule extraction (SMILE) between -9.00 and -13.00 diopters (D)., Methods: This was a prospective study recruiting 114 patients undergoing SMILE with attempted spherical equivalent refraction (SEQ) correction from -9.00 to -13.00 D, and cylinder up to 5.00 D. Patients were informed before surgery of the increased risk of QoV symptoms. Patients completed the Rasch validated QoV questionnaire. Objective QoV was assessed by corneal and whole eye aberrations, HD Analyzer Objective Scatter Index (OSI) (Keeler), and contrast sensitivity. Patient satisfaction was assessed on a scale from 0 (very dissatisfied) to 10 (very satisfied). Individual item and total Rasch-scaled scores for the three subscales (frequency, severity, and bothersomeness) of the QoV questionnaire were calculated before and 12 months after surgery., Results: The mean patient satisfaction score was 9.27 ± 1.18 (range: 2 to 10), 8 or higher in 93%, and 7 or higher in 98% of patients. One patient with a satisfaction score of 2 had a simple refractive error re-treatment and then reported a satisfaction score of 10. The total mean ± standard deviation Rasch-scaled QoV score for the frequency, severity, and bothersomeness subscales before surgery was 24 ± 19, 20 ± 16, and 19 ± 18, respectively. Scores increased after surgery to 41 ± 18, 32 ± 16, and 30 ± 21, respectively ( P < .001). Corneal aberrations (6 mm, OSI) increased on average by 0.39 µm for spherical aberration, 0.41 µm for coma, and 0.56 µm for higher order aberrations root mean square. OSI increased on average by 0.58. There was a small but statistically significant improvement in contrast sensitivity at 3, 6, 12, and 18 cycles per degree. There were no statistically significant correlations found between subjective scores for starbursts and objective measurements., Conclusions: Satisfaction was high following SMILE for high myopia. As expected, there was an increase in QoV symptoms, mainly glare and starbursts. The acceptance of QoV symptoms for high myopic SMILE was high, indicating that residual refractive error and visual acuity are the major drivers for patient satisfaction with appropriate preoperative informed consent. [ J Refract Surg . 2022;38(7):404-413.] .

Purpose of Review: As more devices become available that offer corneal epithelial thickness mapping, this is becoming more widely used for numerous applications in corneal refractive surgery., Recent Findings: The epithelial thickness profile is nonuniform in the normal eye, being thinner superiorly than inferiorly and thinner temporally than nasally. Changes in the epithelial thickness profile are highly predictable, responding to compensate for changes in the stromal curvature gradient, using the eyelid as an outer template. This leads to characteristic changes that can be used for early screening in keratoconus, postoperative monitoring for early signs of corneal ectasia, and for determining whether further steepening can be performed without the risk of apical syndrome following primary hyperopic treatment. Compensatory epithelial thickness changes are also a critical part of diagnosis in irregular astigmatism as these partially mask the stromal surface irregularities. The epithelial thickness map can then be used to plan a trans-epithelial PRK treatment for cases of irregularly irregular astigmatism. Other factors can also affect the epithelial thickness profile, including dry eye, anterior basement membrane dystrophy and eyelid ptosis., Summary: Epithelial thickness mapping is becoming a crucial tool for refractive surgery, in particular for keratoconus screening, ectasia monitoring, hyperopic treatment planning, and therapeutic diagnosis and treatment., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: To assess the repeatability of corneal epithelial thickness mapping in virgin, post-laser refractive surgery (PLRS), and keratoconic eyes using a novel swept-source optical coherence tomographer (SS-OCT), and to determine the agreement of the measurements with a validated spectral-domain (SD) OCT., Methods: Analysis of 90 virgin, 46 PLRS, and 122 keratoconic eyes was performed. Three consecutive measurements of each eye were acquired with the Anterion SS-OCT and Avanti SD-OCT devices, and averages of the epithelial thickness mapping were calculated in the central 2-mm zone and in the 2- to 5-mm and 5- to 7-mm diameter rings. The repeatability was analyzed using pooled within-subject standard deviation (S w ). The agreement was assessed by Bland-Altman analysis and paired t tests., Results: The repeatability ranges of the Anterion and Avanti epithelial thickness mapping measurements were S w : 0.60 to 1.36 µm and S w : 0.75 to 1.96 µm, respectively. The 95% limits of agreement of the Anterion and Avanti were 0.826 to 8.297. All values of the thickness measurements with the Anterion were lower than those of the Avanti, with the mean differences being 4.06 ± 1.81, 3.26 ± 2.52, and 3.68 ± 2.51 µm in virgin, PLRS, and keratoconic eyes, respectively ( P < .001 for all)., Conclusions: The repeatability of the Anterion's epithelial thickness mapping was higher than that of the Avanti. In terms of the agreement between the Anterion and Avanti, the epithelium measured by the Anterion was always thinner than that of the Avanti, making their interchangeable use unsuitable without corrections. [ J Refract Surg . 2022;38(6):356-363.] .

Significance: Corneal epithelial thickness mapping has a wide range of applications including screening for keratoconus, screening for anterior basement membrane dystrophy, and assessment of dry eye. It also plays an important role in corneal laser refractive surgery. These all require an understanding of the epithelial thickness profile in a normal cornea as a reference., Purpose: This study aimed to compare corneal epithelial thickness along different meridians in normal eyes with different types of corneal astigmatism., Methods: In this cross-sectional study, corneal topography and epithelial thickness mapping by anterior segment optical coherence tomography was performed for 154 normal eyes. Corneal astigmatism was classified based on the orientation of the steepest corneal meridian (with-the-rule [WTR], against-the-rule [ATR], and oblique) and the amount (low, moderate, and high). On a 9-mm epithelial thickness map, the thickness along the horizontal (180°), vertical (90°), and diagonal (45 and 135°) meridians was calculated., Result: With-the-rule, oblique, and ATR astigmatisms were observed in 40, 31, and 29% of the eyes, respectively. In all types of astigmatism, the mean epithelial thickness was greater along the 180° meridian and thinner along the 90° meridian. There was no statistically significant difference in mean thickness along different meridians for WTR (P = .24) and oblique (P = .46) astigmatism, whereas the difference along the 180 and 90° meridians (P = .003) for ATR astigmatism was statistically significant. Also, there was a statistically significant difference in thickness in different types of astigmatism separately for each meridian (P < .05) so that the highest and lowest thicknesses were seen for ATR and oblique astigmatisms, respectively. The epithelial thickness showed no statistical difference in various amounts of astigmatism along different meridians., Conclusions: Thicker epithelium along the horizontal meridian in ATR may point to the surface regularizing functions of the epithelium to create a regular and smooth surface, but thickness assessment along the different meridians in oblique and WTR showed no curvature-dependent changes., Competing Interests: Conflict of Interest Disclosure: DZR is a consultant for Carl Zeiss Meditec (Carl Zeiss Meditec AG, Jena, Germany) and has a proprietary interest in the Artemis Insight 100 technology (ArcScan Inc., Golden, CO) through patents administered by the Cornell Center for Technology Enterprise and Commercialization, Ithaca, NY. The remaining authors have no proprietary or financial interest in the materials presented herein., (Copyright © 2022 American Academy of Optometry.)

Purpose: To identify parameters influencing the postoperative vault of the Implantable Collamer Lens (ICL) (STAAR Surgical) using the Artemis Insight 100 very high-frequency (VHF) digital ultrasound robotic scanner (ArcScan, Inc) and develop a model to improve lens vault prediction., Methods: This was a retrospective analysis of 147 consecutive V4c EVO and EVO+ ICL implantation procedures performed over three phases in myopic eyes. In the initial phase, lens size was defined by published sulcus-to-sulcus and crystalline lens rise measurements (Kojima formula) from VHF digital ultrasound biometry. From these data, a stepwise multivariate regression analysis was performed to develop a model for predicting central vault including the following variables: ICL size, ICL power, sulcus-to-sulcus (STS), ciliary body inner diameter (CBID), zonule-to-zonule, STS lens rise (STSL), ACD, anterior chamber angle, scotopic pupil diameter (SPD), angle-to-angle, and white-to-white diameter. The resulting regression model was used in coordination with the Kojima formula to select the lens size for the next series of eyes. The regression analysis was then repeated and a further series were treated. The postoperative achieved vault at 1 month was compared to the target vault predicted by the formula. A comparison analysis of the new model was made to previously published lens sizing formulas., Results: Statistically significant variables were ICL size, ICL power, CBID, STSL, and SPD. The primary 42 eyes (Kojima formula) achieved a mean vault of 506 ± 233 µm, a range of 810 µm (114 to 924 µm), and an interquartile range (IQR) of 391 µm. Using the Reinstein formula v1.0 for the next 36 eyes, the mean vault relative to target was +7 ± 123 µm, range of 569 µm (-278 to +291 µm), and IQR of 169 µm. Using the Reinstein formula v2.0 for the next 69 eyes, the mean vault relative to target was +67 ± 121 µm, range of 573 µm (-219 to +354 µm), and IQR of 131 µm. The achieved vault was within ±100, ±200, and ±300 µm of target in 33%, 50%, and 74% of eyes, respectively, for the training group, 58%, 89%, and 100% for the Reinstein formula v1.0 group, and 62%, 84%, and 94% for the Reinstein formula v2.0 group., Conclusions: This is the first report describing the ciliary body inner diameter, which proved to be more highly correlated with vault than STS, and thus CIBD supersedes STS from the previous widely accepted improvement over WTW sizing. The new model also found scotopic pupil size to be a significant predictor, which has not been a part of any previously published model. The significant improvement in vault predictability afforded by these parameters and the new model enables charting attempted versus achieved vault outcomes for the first time. [ J Refract Surg . 2022;38(5):272-279.] .

Purpose: Assess the mid and peripheral neuroretina and vitreoretinal interface using a novel Navigated Single-Capture 3D and Cross-Sectional Wide-Field Swept-Source Optical Coherence Tomography (WF SS-OCT) technology with correlation to Multi-Wavelength Ultra-Widefield Imaging (MW UWFI) and Histopathology reference., Methods: Retrospective observational study. A total of 74 patients (148 eyes) were imaged using WF SS-OCT and Navigated Single-Capture twelve 23 mm cross-sectional radial scan pattern at 15° intervals. Image diagnosis included: congenital hypertrophy of the retinal pigment epithelium, choroidal nevus, ora serrata pearls, retinal tuft, lattice, snail track, cobblestone degeneration, retinal hole, retinal tear, degenerative retinoschisis, peripheral laser retinopexy, white without pressure, vitreous floaters, subclinical peripheral rhegmatogenous retinal detachment (RD), and tractional RD in proliferative diabetic retinopathy. WF SS-OCT images were correlated with MW UWFI and histopathological references where available., Results: WF SS-OCT successfully imaged structural features in all diagnoses with significant improvement in diagnostic capability and increased the diagnosis of specific features such as vitreoretinal attachment, full thickness hole or tear and subretinal fluid. Histopathological correlation was available for five (5) different peripheral retinal pathologies imaged by both WF SS-OCT and MW UWFI and good anatomical correlation was observed in all diagnosis., Conclusions: Navigated Single-Capture 3D and Cross-Sectional WF SS-OCT provides detailed anatomic information of the mid and peripheral neuroretina and vitreoretinal interface, allowing early recognition of vision-threatening features that may influence clinical management, particularly in an era of telemedicine or when there is limited or no access to Indirect Ophthalmoscopy with 360° Scleral Indentation.

Purpose: To report the outcomes of small incision lenticule extraction (SMILE) for high myopia between -9.00 and -14.00 diopters (D)., Methods: This was a prospective study of SMILE for high myopia using the VisuMax femtosecond laser (Carl Zeiss Meditec). Inclusion criteria were attempted spherical equivalent refraction (SEQ) between -9.00 and -14.00 D, cylinder up to 7.00 D, corrected distance visual acuity (CDVA) of 20/40 or better, age 21 years or older, and suitable for SMILE. The sub-lenticule thickness was 220 µm or greater, and the total uncut stromal thickness was 300 µm or greater. Patients were to be followed up for 1 year. Standard outcomes analysis was performed using 12-month data where available or 3-month data otherwise., Results: Of 187 eyes treated, data were available at 12 months for 181 eyes (96.8%) and 3 months for 4 eyes (2.1%), and 2 eyes (1.1%) were lost to follow-up. Mean attempted SEQ was -10.55 ± 1.00 D (range: -9.00 to -12.99 D). Mean cylinder was -1.19 ± 0.83 D (range: 0.00 to -4.00 D). Preoperative CDVA was 20/20 or better in 73% of eyes. Postoperative uncorrected distance visual acuity was 20/20 or better in 57% and 20/25 or better in 82% of eyes. Mean SEQ relative to target was -0.22 ± 0.48 D (range: -1.63 to +1.38 D), 66% ± 0.50 D and 93% ±1.00 D. Mean SEQ 12-month change was -0.08 ± 0.34 D (range: -1.75 to +0.88 D). There was loss of one line of CDVA in 4% of eyes, and no eyes lost two or more lines. Contrast sensitivity was unchanged. Patient satisfaction was 8 or more out of 10 in 94% and 6 or more in 99% of patients., Conclusions: Outcomes of SMILE for myopia greater than -9.00 D at 3 to 12 months showed excellent efficacy, safety, stability, and predictability, with high patient satisfaction. [ J Refract Surg . 2022;38(5):262-271.] .

Purpose: To report 6-month visual and refractive outcomes following PRESBYOND Laser Blended Vision (Carl Zeiss Meditec) treatment using non-linear aspheric micro-anisometropia laser in situ keratomileusis (LASIK) for the correction of myopic and hyperopic presbyopia., Methods: A retrospective, non-comparative study of 139 consecutive patients with a mean age of 53.13 ± 5.84 years (range: 42 to 70 years) treated with LASIK-induced micro-anisometropia using the MEL 90 excimer laser and VisuMax femtosecond laser (both Carl Zeiss Meditec). The target refraction was plano for distance eyes (dominant eye) and between -0.50 and -1.50 diopters (D) for near eyes. Patients were observed for 6 months., Results: A total of 278 eyes (78 myopic and 200 hyperopic) from 139 patients completed the study. Mean preoperative spherical equivalent (SE) was -3.40 ± 1.83 D (range: -0.50 to -8.25 D) for myopic eyes and +1.61 ± 0.98 D (range: -1.25 to +4.63 D) for hyperopic eyes. Mean postoperative SE refraction of distance eyes was +0.20 ± 0.35 D (range: -0.38 to +1.00 D) and -0.14 ± 0.42 D (range: -1.38 to +0.88 D) for myopic and hyperopic eyes, respectively. Mean postoperative SE refraction of near eyes was -0.90 ± 0.44 D (range: -0.13 to -2.25 D) and -1.21 ± 0.48 D (range: -0.13 to -2.25 D) for myopic and hyperopic eyes, respectively. Mean binocular uncorrected near visual acuity was 0.70 ± 0.28 logMAR (range: 0.32 to 1.00 logMAR) and 0.79 ± 0.27 logMAR (range: 0.25 to 1.00 logMAR) for myopic and hyperopic eyes, respectively. Mean binocular uncorrected distance visual acuity was 1.19 ± 0.18 logMAR (range: 0.63 to 1.25 logMAR) and 1.14 ± 0.26 logMAR (range: 0.40 to 1.25 logMAR) for myopic and hyperopic eyes, respectively. Stereoacuity was better than 100 seconds of arc in 79% of myopic eyes and 85% of hyperopic eyes and all vision quality scores were greater than 90 of 100. No eyes lost two or more lines., Conclusions: The non-linear aspheric micro-anisometropia protocol resulted in safe and effective visual outcomes in patients with both myopic and hyperopic presbyopia. [ J Refract Surg . 2022;38(5):288-297.] .

Purpose: To describe a new technique for identifying the upper (cap) interface during small-incision lenticule extraction (SMILE). If the lower interface is dissected first it can be challenging to locate the cap interface and complete the lenticule separation., Setting: London Vision Clinic, London, United Kingdom., Design: Retrospective analysis., Methods: The routine protocol was to open the primary small incision and separate the cap interface, followed by the lenticule interface. If the lenticule interface was dissected first, the modified Sinskey tip was inserted through the superior end of the incision, tangentially along the cap edge interface and then rotated anteriorly to engage the edge of the lenticule adherent to the underside of the cap. The Sinskey tip is then drawn inferiorly, creating a pocket of separation of the lenticule from the cap, enabling the dissection bulb and spatula to be used to dissect the upper interface., Results: A total of 629 consecutive eyes undergoing SMILE using the VisuMax femtosecond laser were included. The routine surgical protocol (cap interface first) was followed in 88% of eyes and the lenticule interface first in 12% of eyes. The lenticule was extracted successfully in all cases. Uncorrected distance visual acuity at the 1-day postoperative visit was 20/25 or better in 81% of the cap interface first group and 86% of the lenticule interface first group., Conclusions: The visual results using this cap recovery technique were equivalent to those when a routine SMILE dissection was performed. The technique allowed surgeons to rescue more challenging cases where identifying the different interfaces was difficult. This technique meant that separating the lenticule interface first should no longer be considered a complication of SMILE., (Copyright © 2021 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To assess intraoperative stromal topography measurements using swept-source optical coherence tomography (OCT)-based topography/tomography after epithelial removal and to analyze the epithelial contribution to the corneal topography and optics., Methods: This was a prospective series of 22 eyes of 19 patients referred to receive phototherapeutic keratotomy (PTK) for treatment of recurrent corneal erosion and a control group of 22 virgin eyes. Swept-source OCT corneal topography/tomography was obtained immediately before and immediately after mechanical deepithelialization before PTK. Epithelial thickness maps were obtained before the surgery using spectral-domain OCT in the control group and as a reference in the group with anterior basement membrane dystrophy. Topographic and optical characteristics, including the curvature, astigmatism, asphericity, and higher order aberrations of the cornea before and after deepithelialization were compared, and their differences correlated with the measurements derived from the epithelial thickness maps., Results: Stromal topography measurements after deepithelialization were easily obtained and showed excellent repeatability. Assessment of corneal edema induced by deepithelialization revealed that it did not significantly affect the measured parameters. The stromal surface was steeper by 1.28 diopters, had higher with-the-rule astigmatism by 0.41 diopters, was more prolate, and had more higher order aberrations compared to the intact epithelialized corneal surface. These differences correlated well with the parameters derived from epithelial thickness maps., Conclusions: Measurement of stromal topography using swept-source OCT immediately after mechanical deepithelialization may be a viable method in therapeutic refractive surgery, where stromal topography-guided ablation is needed. A significant epithelial contribution to anterior corneal topography and optics was confirmed. [ J Refract Surg . 2021;37(7):484-492.] .

Purpose: To assess epithelial corneal remodeling by anterior segment optical coherence tomography (AS-OCT) after intracorneal ring segments (ICRS) implantation in keratoconic eyes., Methods: This prospective observational study included patients with keratoconus receiving ICRS of different arc lengths according to their tomographic pattern. AS-OCT and corneal topography (Scheimpflug camera) were performed before and 1, 3, and 6 months after surgery. Corneal pachymetry mapping was performed and total corneal and epithelial thicknesses (3-mm central and 16 points on 6-mm zone) were measured over the pupil center using AS-OCT. Topographic parameters were also assessed., Results: A total of 68 keratoconic eyes were analyzed (Amsler-Krumeich stages 1 to 4) in four groups of 17 eyes: 210° ICRS, 320° ICRS, double 160° ICRS, and single 160° ICRS. Corneal pachymetry mapping revealed that epithelial thickness increased significantly in the internal zones juxtaposed to the ICRS without smoothing during the postoperative period ( P < .05). Mean maximum epithelial thickness increased from 67 ± 6 to 79 ± 7 µm for 210° ICRS, 66 ± 9 to 82 ± 4 µm for 320° ICRS, 63 ± 6 to 78 ± 7 µm for double 160° ICRS, and 62 ± 5 to 77 ± 5 µm for single 160° ICRS ( P < .0001). Significant epithelial thickening at the apex of the cone was observed in all groups ( P < .05)., Conclusions: Significant epithelial thickening occurs after ICRS implantation adjacent to the ICRS to compensate for the ridge created with a thickening of epithelium over the cone due to regularization of the stromal surface. [ J Refract Surg . 2021;37(6):404-413.] .

Purpose: To evaluate the influence of coma on manifest refractive cylinder (MRC) in eyes with coma-dominated corneal optics and suggest alternative guidelines for surgical planning of astigmatism correction in topography-guided ablation and toric intraocular lens (IOL) exchange surgery., Methods: Twelve eyes with coma-dominant corneal optics and low lenticular astigmatism were selected. The astigmatism remaining after subtraction of total corneal astigmatism (TCA) and lenticular astigmatism from MRC, termed discrepant astigmatism, was calculated and correlated to corneal coma at the anterior surface. Refractive and topography data were then used to simulate topography-guided refractive surgery (topography-guided group) in 7 eyes and lenticular exchange surgery with toric intraocular lens (IOL) implantation (toric IOL group) in 5 eyes. The estimated postoperative MRC after correction of TCA or MRC for each group was compared., Results: The axis and amplitude of discrepant astigmatism correlated strongly with the axis and amplitude of coma. In the topography-guided group, where topography-guided ablation eliminated corneal higher order aberrations (HOAs), TCA-based correction led to less estimated postoperative manifest astigmatism than MRC-based correction. In the toric IOL group, where removal of the crystalline lens did not affect corneal HOAs, MRC-based correction via toric IOL implantation led to less estimated postoperative astigmatism than TCA-based correction., Conclusions: Discrepant astigmatism in eyes with coma-dominant corneal optics correlates with coma. In such eyes, treating TCA, along with corneal HOAs, instead of MRC, seems appropriate in topography-guided treatments, whereas treating MRC may be a better choice in lenticular exchange surgery with toric IOL implantation, where corneal HOAs are not treated. [ J Refract Surg . 2021;37(4):274-282.] .

Refractive surgery refers to any procedure that corrects or minimizes refractive errors. Today, refractive surgery has evolved beyond the traditional laser refractive surgery, embodied by the popular laser in situ keratomileusis or 'LASIK'. New keratorefractive techniques such as small incision lenticule extraction (SMILE) avoids corneal flap creation and uses a single laser device, while advances in surface ablation techniques have seen a resurgence in its popularity. Presbyopic treatment options have also expanded to include new ablation profiles, intracorneal implants, and phakic intraocular implants. With the improved safety and efficacy of refractive lens exchange, a wider variety of intraocular lens implants with advanced optics provide more options for refractive correction in carefully selected patients. In this review, we also discuss possible developments in refractive surgery beyond 2020, such as preoperative evaluation of refractive patients using machine learning and artificial intelligence, potential use of stromal lenticules harvested from SMILE for presbyopic treatments, and various advances in intraocular lens implants that may provide a closer to 'physiological correction' of refractive errors.

Purpose: To report the distribution of pupil offset and angle kappa in 750 myopic, emmetropic, and hyperopic eyes presenting for refractive surgery., Methods: A retrospective study included 750 consecutive eyes screened for corneal refractive surgery between January 2006 and February 2013. The eyes were divided into three equal groups based on manifest refraction spherical equivalent (SEQ): emmetropic group between -0.25 and +0.50 diopters (D) and cylinder up to 1.00 D, myopic group greater than -0.50 D, and hyperopic group greater than +0.50 D. Angle kappa was measured with the Orbscan II software (Bausch & Lomb, Inc) and pupil offset defined as the distance at the corneal plane between the corneal vertex and the pupil center. Correlations with SEQ, cylinder, scotopic pupil diameter, average keratometry, and age were performed., Results: All results are reported for myopic, emmetropic, and hyperopic groups, respectively. Mean SEQ was -4.84 ± 2.89 D (range: -0.88 to -14.00 D), +0.21 ± 0.23 D (range: -0.25 to +0.50 D), and +2.44 ± 1.58 D (range: +0.63 to +7.75 D). Mean pupil offset magnitude was 0.27 ± 0.14 mm (range: 0.00 to 0.68 mm), 0.34 ± 0.14 mm (range: 0.02 to 0.78 mm), and 0.39 ± 0.13 mm (range: 0.07 to 0.75 mm). Mean pupil offset X-component was -0.18 ± 0.18, -0.28 ± 0.16, and -0.34 ± 0.15 mm (temporally displaced from the corneal vertex). Mean pupil offset Y-component was 0.06 ± 0.15, 0.03 ± 0.16, and 0.01 ± 0.16 mm (superiorly displaced from the corneal vertex). Multivariate linear regression for pupil offset magnitude found statistically significant variables were SEQ, cylinder, scotopic pupil diameter, and average keratometry. For pupil offset X-component, significant variables were SEQ, cylinder, and scotopic pupil diameter. For pupil offset Y-component, significant variables were SEQ and scotopic pupil diameter. Mean angle kappa was 5.28 ± 1.49°, 6.14 ± 1.44°, and 5.77 ± 1.29°., Conclusions: Contrary to common belief, a pupil offset is present in the vast majority of eyes regardless of refractive error, with the mean temporal offset of at least 0.18 mm. Confirming previous studies, the largest pupil offset was found in the hyperopic group. However, there was also a wide range of pupil offset in myopic and emmetropic eyes. Correlations with SEQ and keratometry support the theory that pupil offset is also correlated with axial length. [J Refract Surg. 2021;37(1):49-58.]., (Copyright 2021, SLACK Incorporated.)

Purpose: To describe the visual outcomes of correcting moderate to high hyperopia after two different surgical procedures of lenticular implantation., Methods: This prospective small case series study used epikeratophakia combined with transepithelial phototherapeutic keratectomy (PTK-EP) and femtosecond laser-assisted lenticule intrastromal keratoplasty (LIKE) using myopic small incision lenticule extraction (SMILE)-derived refractive lenticule for correcting hyperopia ranging from +3.00 to +10.00 diopters (D). The implanted refractive lenticule was matched with the recipient's manifest refraction. The visual, refractive, corneal tomographic, and epithelial thickness outcomes were analyzed after surgery., Results: Four eyes underwent PTK-EP and 6 eyes underwent LIKE. At the last postoperative visit, 6 of 10 eyes had uncorrected distance visual acuity equal to or better than the preoperative corrected distance visual acuity (CDVA). No eyes lost one line or more of CDVA postoperatively. Postoperative spherical equivalent was within ±0.50 D of the target for 9 of 10 eyes. Posterior corneal curvature slightly steepened for PTK-EP and LIKE. Postoperative epithelial thickness demonstrated the expected doughnut pattern in both groups characterized by epithelium in the central zone (5 mm) thinner than that in the peripheral zone (5 to 7 mm)., Conclusions: Visual outcomes, refraction, posterior corneal surface changes, and epithelial remodeling after PTKEP or LIKE show a potentially useful modality for correcting moderate to high hyperopia. [J Refract Surg. 2020;36(11):772-779.]., (Copyright 2020, SLACK Incorporated.)

Purpose: To compare clinical outcomes of small-incision lenticule extraction (SMILE) between manifest refraction (MR) and vector planning for myopic astigmatism with high ocular residual astigmatism (ORA)., Setting: Yonsei University College of Medicine and Eyereum Eye Clinic, Seoul, South Korea., Design: Prospective, randomized, comparative case series., Methods: Patients with myopic astigmatism and ORA of 0.75 diopters (D) or greater were randomized into the MR or vector planning group and underwent SMILE without applying any nomogram for cylinder correction. Visual acuity, MR, corneal topography, and corneal aberration were measured preoperatively and postoperatively. Outcomes at 6 months postoperatively were compared between the groups., Results: The study comprised 114 patients (114 eyes): 58 eyes in MR planning and 56 eyes in vector planning. The mean uncorrected and corrected distance visual acuity, safety and efficacy indices were comparable between the 2 groups. Postoperative refractive cylinder reached statistically significant differences between the groups (-0.22 ± 0.18 D and -0.14 ± 0.16 D in the MR and vector planning groups, respectively, P = .02). Postoperative corneal toricity and ORA reached statistically significant lower in the vector planning group., Conclusions: In myopic astigmatism with high ORA, MR and vector planning in SMILE were effective with comparable visual outcomes; vector planning showed statistically significant lower postoperative refractive and corneal astigmatism and ORA. Use of vector planning may improve refractive outcomes in SMILE cases with high ORA. However, the results may have been different had a nomogram adjustment been applied, as is often used for cylinder corrections with SMILE.

Two cases of epithelial implantation after small-incision lenticule extraction (SMILE) treated by Nd:YAG laser and interface sweeping are described. A 40-year-old woman and 33-year-old man underwent SMILE and subsequently were noted to have epithelial cells implanted into the surgical interface. One case was treated using Nd:YAG laser. The laser was focused to the level of the interface with an energy level of 0.3 mJ. The treatment covered the entire area of epithelial implantation. The second case was treated by opening the original SMILE incision and sweeping the residual epithelial cells from the interface followed by a washout. Both the Nd:YAG laser and interface sweeping proved to be effective in reducing or eliminating the epithelial cells from the SMILE interface. Further studies are needed to report on overall safety and efficacy of these 2 techniques.

Purpose: To report the incidence and outcomes of suction loss during small incision lenticule extraction (SMILE)., Methods: The incidence of suction loss was measured over 4000 consecutive SMILE procedures and categorized by cause, the interface in which suction was lost and management (restart/continue SMILE, re-SMILE thinner cap, convert to laser in-situ keratomileusis [LASIK]). One-year outcomes were compared to the fellow eye where no suction loss occurred., Results: There were 20 cases of suction loss (0.50%): during the lenticule interface in seven eyes, lenticule side cut in one eye, cap interface in nine eyes and small incision for three eyes. Small incision lenticule extraction (SMILE) was continued in seven eyes, thinner cap SMILE in four eyes, LASIK in eight eyes, and the small incision was manually completed in one eye. Suction loss was caused by a Bell's reflex in 10 eyes, fixation light tracking in six eyes, patient anxiety in two eyes, a nociceptive reflex in one eye and false suction in one eye. There was no difference in results for suction loss and fellow eyes, respectively: uncorrected distance visual acuity was 20/20 or better in 100% in both groups, spherical equivalent was within ±0.50 D in 85% and 79%, one line loss of corrected distance visual acuity in 5% and 0%, and no eyes lost two lines., Conclusion: Suction loss can be managed depending on the interface during which suction is lost. Treatment was completed on the same day in all instances. Visual and refractive outcomes were unaffected compared to the fellow eye in this series., (© 2019 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)