COVID-19 reduced scleral buckling training in fellows and shifted young ophthalmologists' preference toward vitrectomy: An Asia-Pacific survey.

BACKGROUND: To assess rhegmatogenous retinal detachment (RRD) surgery trends and training among young ophthalmologists (YOs, vitreoretinal fellows or attendings/consultants with ≤10 years of independent practice) and the impact of the COVID-19 pandemic. METHODS: An anonymous online survey was completed by 117 YOs in the Asia-Pacific regarding their RRD surgery experiences in 2021-2022. RESULTS: To achieve a 90% probability of surgical competency, 91 vitrectomy and 34 scleral buckling (SB) completions during fellowship were needed. In total, 49 (41.9%) YOs had fellowship affected by COVID-19. In the COVID versus pre-COVID era, however, the volume of SB completions per fellowship year decreased significantly (median [IQR] 3.3 [1.5, 9] vs. 13 [6.5, 23]; p < 0.001) and was lower than the required volume to achieve competency. YOs were less confident in conducting SB versus vitrectomy (3.5 ± 1.1 vs. 4.2 ± 0.8, p < 0.001), and they reported a decrease in the proportion of SB (-3.1%, p = 0.047) and an increase in the proportion of vitrectomy (+4.8%, p < 0.001) after the pandemic outbreak. Apart from RRD clinical characteristics, surgical confidence is among the main factors that affect surgical method decisions. During the pandemic, more YOs may have avoided SB due to the need for general anaesthesia, leading to longer surgical time and risk of viral transmission during intubation/extubation. CONCLUSIONS: SB surgical exposure is suboptimal in most fellowship programs in the 11 Asia-Pacific countries/regions we surveyed and further declined during the COVID-19 pandemic. YOs are less confident in performing SB, leading to a trend toward primary vitrectomy since the COVID-19 outbreak.

PREVALENCE AND CHARACTERISTICS OF MULTIFOCAL CHOROIDITIS/PUNCTATE INNER CHOROIDOPATHY IN PATHOLOGIC MYOPIA EYES WITH PATCHY ATROPHY.

PURPOSE: To determine the prevalence and characteristics of multifocal choroiditis/punctate inner choroidopathy (MFC/PIC) in eyes with patchy atrophy because of pathologic myopia. METHODS: Five hundred eyes of 253 patients with patchy atrophy were examined between 2014 and 2020 at the Advanced Clinical Center for Myopia. The main outcome measures included the prevalence and characteristics of active MFC/PIC lesions diagnosed by optical coherence tomography. RESULTS: Fifty-five of the 500 eyes (11%) diagnosed with patchy atrophy had optical coherence tomography features of active MFC/PIC lesions, such as focal elevations of the retinal pigment epithelium filled with medium hyperreflectivity material, curvilinear scars (Schlaegel lines), and/or areas of outer retinal atrophy. At the time when the MFC/PIC was diagnosed, the mean age was 57.3 ± 12.0 years, and the mean axial length was 29.2 ± 1.8 mm. Macular neovascularization was found in 45 of eyes (81.8%) with MFC/PIC versus 151 eyes without such findings (33.9%; P < 0.001). In 25 of the 55 eyes (45.5%), active MFC/PIC lesions were found before the development of the patchy atrophy. The Bruch membrane defects were colocated with these lesions. CONCLUSION: Active MFC/PIC lesions were identified in a minority of eyes with pathologic myopia, and a subset of these lesions were observed to progress to findings indistinguishable from myopic patchy atrophy. Evidence of MFC/PIC in eyes with pathologic myopia appeared to be a risk factor for the development of macular neovascularization.

Genotypic Homogeneity in Distinctive Transforming Growth Factor-Beta Induced (TGFBI) Protein Phenotypes.

Background: To evaluate the distribution of the transforming growth factor-beta induced (TGFBI) corneal dystrophies in a multi-ethnic population in Singapore, and to present the different phenotypes with the same genotype. Methods: This study included 32 patients. Slit lamp biomicroscopy was performed for each patient to determine the disease phenotype. Genomic DNA was extracted from the blood samples and the 17 exons of the TGFBI gene were amplified by PCR and sequenced bi-directionally for genotype analysis. Results: Regarding phenotypes, the study patients comprised 11 (34.4%; 8 with R555W and 3 with R124H mutation) patients with granular corneal dystrophy type 1 (GCD1), 6 (18.8%; 5 with R124H and 1 with R124C mutation) patients with GCD2, 13 (40.6%; 7 with R124C, 2 with H626R, 2 with L550P, 1 with A620D and 1 with H572R) patients with lattice corneal dystrophy (LCD) and 2 (6.3%; 1 with R124L and 1 with R124C) patients with Reis-Bückler corneal dystrophy. Regarding genotype, R124H mutation was associated with GCD2 (5 cases; 62.5%) and GCD1 (3 cases; 37.5%). R124C mutation was associated with LCD (7 cases; 87.5%) and GCD2 (1 case; 12.5%). All the 8 cases (100%) of R555W mutation were associated with GCD1. Conclusions: Although the association between genotype and phenotype was good in most cases (65.7%; 21 of 32 patients), genotype/phenotype discrepancy was observed in a significant number.

DIABETIC MACULAR ISCHEMIA: Correlation of Retinal Vasculature Changes by Optical Coherence Tomography Angiography and Functional Deficit.

PURPOSE: To examine the relationship between macular microvasculature parameters and functional changes in persons with diabetic retinopathy (DR). METHODS: Cross-sectional study of 76 eyes with varying levels of DR. Optical coherence tomography angiography (OCTA) quantified superficial and deep perifoveal vessel densities and foveal avascular zone areas. Retinal sensitivity was measured using microperimetry. Optical coherence tomography angiography parameters and retinal sensitivity were correlated. RESULTS: Deep perifoveal vessel density decreased with increasing severity of DR (adjusted mean 51.93 vs. 49.89 vs. 47.96, P-trend = 0.005). Superficial and deep foveal avascular zone area increased with increasing DR severity (adjusted mean: 235.0 µm vs. 303.4 µm vs. 400.9 µm, P-trend = 0.003 [superficial]; 333.1 µm vs. 513.3 µm vs. 530.2 µm, P-trend = 0.001 [deep]). Retinal sensitivity decreased with increasing DR severity (adjusted mean: 25.12 dB vs. 22.34 dB vs. 20.67 dB, P-trend = 0.003). Retinal sensitivity correlated positively with deep perifoveal vessel density (Pearson's ρ = 0.276, P = 0.020) and inversely with superficial foveal avascular zone area (Pearson's ρ = -0.333, P = 0.010). CONCLUSION: Alterations in retinal microvasculature can be observed with OCTA with increasing severity of DR. These changes are correlated with reduced retinal sensitivity. Optical coherence tomography angiography is useful to detect and quantify the microvasculature properties of eyes with diabetic macular ischemia.

PEDIATRIC RETINAL DETACHMENT IN AN ASIAN POPULATION WITH HIGH PREVALENCE OF MYOPIA: Clinical Characteristics, Surgical Outcomes, and Prognostic Factors.

PURPOSE: To evaluate the clinical characteristics and surgical outcomes of pediatric retinal detachments (RDs) in an Asian population. METHODS: Retrospective review of 171 eyes of 152 pediatric patients with rhegmatogenous RD over a 20-year period. RESULTS: Myopia was the most common risk factor in our population. At 6 months, primary anatomical success was 60.7%, and overall anatomical success was 86.7%. A total of 46.8% had best-corrected visual acuity of 20/40 or better, and 81.6% had best-corrected visual acuity of 20/200 or better. In primary RDs, high myopia (≤-6D) patients had a lower primary anatomical success compared to patients with moderate myopia (≤-2D) (59.3 vs. 100% P = 0.03). Increasing age and absence of proliferative vitreoretinopathy were associated with anatomical and visual success. Pars plana vitrectomy as the primary procedure was associated with decreased odds of anatomical success. A longer duration of symptoms, cataract, and a larger RD extent were associated with poorer functional outcome. CONCLUSION: Myopia was the commonest risk factor for pediatric RD in our population. Good anatomical and functional outcome can be achieved with surgery. Increasing age at presentation and absence of proliferative vitreoretinopathy was associated with anatomical and functional success. High myopia was associated with poorer anatomical and functional outcome.

CHARACTERIZATION OF THE CHOROIDAL VASCULATURE IN MYOPIC MACULOPATHY WITH OPTICAL COHERENCE TOMOGRAPHIC ANGIOGRAPHY.

PURPOSE: To characterize the choriocapillaris (CC) in highly myopic eyes with myopic maculopathy, using optical coherence tomographic angiography. METHODS: Prospective, clinic-based study of 42 eyes of 38 patients with high myopia (≤-6 diopters and axial length ≥26.5 mm). Myopic maculopathy was graded from fundus photographs according to the Meta-Analysis for Pathologic Myopia classification. Macular 3 × 3 mm en face optical coherence tomographic angiographic images were obtained with swept-source optical coherence tomographic angiography and graded for CC flow impairment as follows: 1) intact CC, 2) focal (<1 mm), and 3) extensive (>1 mm). RESULTS: Of the 42 eyes, 17 (39.5%) had tessellated fundus, 20 (46.5%) had diffuse, and 6 (14.0%) had patchy atrophy. Choriocapillaris flow impairment was observed in all eyes with diffuse and patchy atrophy. Even in eyes with tessellated fundus only, CC signal voids were seen in 3 eyes (17.6%). With increasingly severe myopic maculopathy, the pattern of CC flow impairment changed from predominantly focal to predominantly extensive. CONCLUSION: Choriocapillaris flow impairment was observed in many highly myopic eyes, even in those with mild fundus changes, and worsened with increasing severity of myopic maculopathy. Longitudinal studies are needed to assess whether CC flow impairment predicts the risk of myopic maculopathy progression.

Randomized controlled trial evaluating a novel community eye care programme for elderly individuals with visual impairment.

IMPORTANCE: The novel intervention was effective at improving compliance to appropriate tertiary eye care after community eye screening. BACKGROUND: Elderly individuals from low socio-economic background with visual impairment (VI) often do not attend tertiary care, even if significant eye diseases are detected while in the community. We evaluate a novel incentive care scheme (ICS) to improve compliance to appropriate follow-up after community eye screening. DESIGN: Randomized controlled trial in a population-based setting was conducted. PARTICIPANTS: A total of 140 elderly individuals with VI (visual acuity <6/12, mean age ± SD = 66.6 ± 8.9 years, 46.4% female) were included. METHODS: Participants were randomized to either ICS (N = 72) or usual care (UC; N = 68). ICS incorporated patient education, social support and financial assistance to assist individuals in attending tertiary eye care. UC comprised of a standard referral letter and advice. MAIN OUTCOME MEASURE: Primary outcome included compliance to eye care referral. Secondary outcomes included best-corrected visual acuity and vision-related quality of life assessed at baseline and 3 months. RESULTS: Participants receiving the ICS intervention had higher rates of compliance to tertiary eye care attendance compared to UC (31.9% vs. 16.2%, respectively, P = 0.027). While we observed an overall significant improvement in best-corrected visual acuity at 3 months in both groups (P < 0.05), we found no significant differences in Rasch-transformed vision-related quality of life scores between groups (all P > 0.05). Identified barriers for tertiary healthcare access included patient attitudes and financial- and health-related barriers. CONCLUSION AND RELEVANCE: Our pilot RCT found that ICS improved adherence to appropriate tertiary eye care referrals after community eye screening in elderly people with VI.

Longitudinal Changes in Disc and Retinal Lesions Among Highly Myopic Adolescents in Singapore Over a 10-Year Period.

OBJECTIVES: To examine the progression pattern of disc and retinal lesions in highly myopic Chinese adolescents over a 10-year period in Singapore. METHODS: This longitudinal study included Chinese participants who showed high myopia (spherical equivalent [SE] worse than or equal to -5 diopters [D]), no history of refractive surgery, and available fundus photographs at both 2006 (baseline) and 2016 (10-year follow-up) visits. Forty-four adolescents (aged 12-16 years at baseline) who were re-examined later at follow-up were included. Cycloplegic refraction, biometry, and fundus photography were performed at both visits. A trained grader classified myopic macular degeneration (MMD) based on the Meta-pathologic myopia classification and disc lesions from fundus photographs. Choroidal thickness (CT) measurements were performed at 10-year follow-up using swept-source optical coherence tomography. The ocular parameters and lesions were compared between baseline and follow-up. RESULTS: There was a significant worsening of high myopia at follow-up to -7.5±1.8 D (mean SE±SD) in 2016 versus -6.2±1.3 D in 2006; (P<0.001). The 10-year changes included increased degree of tessellation (26 eyes, 29.5%), development of new tessellated fundus (19 eyes, 21.6%), disc tilt (7 eyes, 8.0%), and expansion of peripapillary atrophy size (33 eyes, 37.5%). Eyes with early-onset tessellation (present at baseline, 48 eyes) showed significantly thinner CT (P<0.05), compared with eyes with late-onset tessellation (incident at 10-year follow-up, 19 eyes). No cases of MMD were recorded at baseline or 10-year follow-up. CONCLUSIONS: Although there was no incident MMD, the retinal and disc lesions worsened over the follow-up period. Early-onset fundus tessellation was associated with thinner CT.

Biomarkers of Diabetic Retinopathy.

Diabetic retinopathy (DR), a leading cause of acquired vision loss, is a microvascular complication of diabetes. While traditional risk factors for diabetic retinopathy including longer duration of diabetes, poor blood glucose control, and dyslipidemia are helpful in stratifying patient's risk for developing retinopathy, many patients without these traditional risk factors develop DR; furthermore, there are persons with long diabetes duration who do not develop DR. Thus, identifying biomarkers to predict DR or to determine therapeutic response is important. A biomarker can be defined as a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention. Incorporation of biomarkers into risk stratification of persons with diabetes would likely aid in early diagnosis and guide treatment methods for those with DR or with worsening DR. Systemic biomarkers of DR include serum measures including genomic, proteomic, and metabolomics biomarkers. Ocular biomarkers including tears and vitreous and retinal vascular structural changes have also been studied extensively to prognosticate the risk of DR development. The current studies on biomarkers are limited by the need for larger sample sizes, cross-validation in different populations and ethnic groups, and time-efficient and cost-effective analytical techniques. Future research is important to explore novel DR biomarkers that are non-invasive, rapid, economical, and accurate to help reduce the incidence and progression of DR in people with diabetes.

THREE-YEAR RESULTS OF POLYPOIDAL CHOROIDAL VASCULOPATHY TREATED WITH PHOTODYNAMIC THERAPY: Retrospective Study and Systematic Review.

PURPOSE: To evaluate the 3-year outcome in eyes with polypoidal choroidal vasculopathy (PCV) treated with photodynamic therapy with verteporfin. METHODS: Retrospective study and review of the literature. We performed a retrospective study of patients with PCV who were treated with photodynamic therapy between January 2007 and December 2008. Patients were excluded if they had received photodynamic therapy before the study period, but those who received previous treatment with other modalities (thermal laser or intravitreal therapies) were allowed. The main outcome measures were best-corrected visual acuity, repeat photodynamic therapy, and recurrence of PCV at the end of Years 1, 2, and 3. We further conducted a systematic review of the literature using the terms "polypoidal choroidal vasculopathy" and "photodynamic therapy" and compared the visual outcome of studies over 3 years using meta-analytical methods. RESULTS: The retrospective study included 68 eyes. The mean best-corrected visual acuity was 0.73 ± 0.56 logMAR (20/107, Snellen equivalent) at baseline, 0.73 ± 0.70 logMAR (20/107, Snellen equivalent) at 1 year, 0.96 ± 0.76 logMAR (20/182, Snellen equivalent) at 2 years, and 1.07 ± 0.81 logMAR (20/235, Snellen equivalent) at 3 years. The cumulative recurrence rates of PCV were 16.1% (1 year), 34.9% (2 years), and 52.7% (3 years) and eyes with recurrence were more likely to suffer ≥3 lines loss compared with eyes without recurrence (63.2 vs. 17.6%, P = 0.006). The systematic review summarized results from 48 published studies and our retrospective study. The pooled analysis from 29 studies (316 eyes reporting the 3-year visual outcome) reported mean best-corrected visual acuity improvement of 0.115 logMAR at 1 year (n = 1,669), 0.066 logMAR at 2 years (n = 701), and 0.027 logMAR at 3 years (n = 316). Reported recurrence rates were 5.9% to 50.0% after 1 year, 9.1% to 83.3% after 2 years, and 40.0% to 78.6% after 3 years or longer of follow-up. CONCLUSION: The visual outcome in eyes with PCV was stable until 2 years, but the outcome at 3 years worsened, particularly in eyes that experienced recurrence.

SCLERAL BUCKLING VERSUS VITRECTOMY IN THE MANAGEMENT OF MACULA-OFF PRIMARY RHEGMATOGENOUS RETINAL DETACHMENT: A COMPARISON OF VISUAL OUTCOMES.

PURPOSE: To compare visual outcomes between pars plana vitrectomy (PPV) with or without scleral buckling (SB) and SB alone in the management of uncomplicated macula-off primary rhegmatogenous retinal detachment. METHODS: Case-control study of 723 patients with uncomplicated macula-off primary rhegmatogenous retinal detachment seen at the Singapore National Eye Centre from 2005 to 2011. The primary outcome measure was the proportion of eyes achieving functional success, defined as logMAR best-corrected visual acuity of ≤0.3 logMAR at 6 months postoperatively. Multivariable logistic regression analysis was performed adjusting for the following preoperative covariates: age, gender, race, lens status, number of tears found, presence of proliferative vitreoretinopathy, operative procedure, logMAR best-corrected visual acuity, and duration of symptoms. RESULTS: Three hundred and eight eyes underwent SB alone, and 415 eyes underwent PPV ± SB. In the SB group, 133 eyes (43.2%) achieved functional success compared with 116 eyes (28.0%) in the PPV ± SB group. This difference was statistically significant on both univariate (P < 0.001) and multivariable analyses (OR: 1.51, 95% CI: 1.03-2.21, P = 0.03). CONCLUSION: Scleral buckling alone may achieve visual outcomes that are at least comparable with PPV ± SB in the management of macula-off primary rhegmatogenous retinal detachment.

Kidney and eye diseases: common risk factors, etiological mechanisms, and pathways.

Chronic kidney disease is an emerging health problem worldwide. The eye shares striking structural, developmental, and genetic pathways with the kidney, suggesting that kidney disease and ocular disease may be closely linked. A growing number of studies have found associations of chronic kidney disease with age-related macular degeneration, diabetic retinopathy, glaucoma, and cataract. In addition, retinal microvascular parameters have been shown to be predictive of chronic kidney disease. Chronic kidney disease shares common vascular risk factors including diabetes, hypertension, smoking, and obesity, and pathogenetic mechanisms including inflammation, oxidative stress, endothelial dysfunction, and microvascular dysfunction, with ocular diseases supporting the 'Common Soil Hypothesis.' In this review, we present major epidemiological evidence for these associations and explore underlying pathogenic mechanisms and common risk factors for kidney and ocular disease. Understanding the link between kidney and ocular disease can lead to the development of new treatment and screening strategies for both diseases.

Trends and factors related to outcomes for primary rhegmatogenous retinal detachment surgery in a large asian tertiary eye center.

PURPOSE: To describe trends and outcomes of vitreoretinal surgery for primary rhegmatogenous retinal detachment in a large Asian tertiary eye center. METHODS: Retrospective review of 1,530 eyes with primary retinal detachment between 2005 and 2011 managed at the Singapore National Eye Center by one of the following: scleral buckling (SB), pars plana vitrectomy (PPV), and combined SB and PPV (SB + PPV). Anatomical and functional outcomes were assessed. RESULTS: There was a trend toward PPV and PPV + SB as the primary reattachment procedure from 2005 to 2011. The primary anatomical success rate for PPV (78.6%) was worse than that for SB (88.8%) or SB + PPV (89.0%, P = 0.000). Final anatomical success rates were similar for all 3 procedures: SB 97.7%, PPV 95.2%, and SB + PPV 96.4%. Better functional success was achieved in the SB group (86.1%) than both the PPV (72.5%) and SB + PPV groups (77.5%, P = 0.000), partly attributable to the less complex nature of retinal detachments in the SB group. Older age and proliferative vitreoretinopathy were related to the poor functional outcomes in both phakic and pseudophakic eyes. CONCLUSION: There was an increasing trend toward PPV and PPV + SB as the primary retinal reattachment surgery from 2005 through to 2011. High rates of anatomical and functional outcomes were achieved with SB, PPV, and SB + PPV, proliferative vitreoretinopathy and older age were negatively correlated with the functional success in both phakic and pseudophakic eyes.

Pathologic myopia in highly myopic patients with high axial anisomyopia.

PURPOSE: To determine prevalence of anisomyopia (axial length (AL) difference ≥2.5 mm) among high myopes ((HMs), defined by spherical equivalent of ≤6.0 diopters or AL ≥ 26.5 mm). To characterise the shorter anisomyopic eye (SAE) and evaluate if pathologic myopia (PM) in the longer anisomyopic eye (LAE) was associated with increased risk of PM in the SAE. METHODS: 1168 HMs were recruited from Singapore National Eye Centre clinic for this cross-sectional study. Biometry, fundus photography and swept-source optical coherence tomography were performed. Patients with high axial anisomyopia were identified. Structural characteristics and presence of PM were described. Stepwise multivariate regression explored associations between PM in the LAE and pathology in the SAE, controlling for confounding variables. RESULTS: Prevalence of anisomyopia was 15.8% (184 of 1168 patients). Anisomyopic patients (age 65.8±13.5 years) had mean AL of 30.6±2.0 mm and 26.2±2.3 mm in the LAE and SAE, respectively. 52.7% of SAEs had AL < 26.5 mm. Prevalence of myopic macular degeneration, macula-involving posterior staphyloma (PS), myopic traction maculopathy (MTM) and myopic choroidal neovascularisation (mCNV) in the SAE was 52.2%, 36.5%, 13.0% and 8.2%, respectively. Macular hole in the LAE was associated with increased risk of MTM in the SAE (OR=4.88, p=0.01). mCNV in the LAE was associated with mCNV in the SAE (OR=3.57, p=0.02). PS in the LAE was associated with PS in the SAE (OR=4.03, p<0.001). CONCLUSIONS: Even when controlled for AL, PM complications in the LAE predict similar PM complications in the SAE. Patients with high axial anisometropia with PM in the LAE should be monitored carefully for complications in the SAE.

Comparison of manual and artificial intelligence-automated choroidal thickness segmentation of optical coherence tomography imaging in myopic adults.

BACKGROUND: Myopia affects 1.4 billion individuals worldwide. Notably, there is increasing evidence that choroidal thickness plays an important role in myopia and risk of developing myopia-related conditions. With the advancements in artificial intelligence (AI), choroidal thickness segmentation can now be automated, offering inherent advantages such as better repeatability, reduced grader variability, and less reliance for manpower. Hence, we aimed to evaluate the agreement between AI-automated and manual segmented measurements of subfoveal choroidal thickness (SFCT) using two swept-source optical coherence tomography (OCT) systems. METHODS: Subjects aged ≥ 16 years, with myopia of ≥ 0.50 diopters in both eyes, were recruited from the Prospective Myopia Cohort Study in Singapore (PROMYSE). OCT scans were acquired using Triton DRI-OCT and PLEX Elite 9000. OCT images were segmented both automatically with an established SA-Net architecture and manually using a standard technique with adjudication by two independent graders. SFCT was subsequently determined based on the segmentation. The Bland-Altman plot and intraclass correlation coefficient (ICC) were used to evaluate the agreement. RESULTS: A total of 229 subjects (456 eyes) with mean [± standard deviation (SD)] age of 34.1 (10.4) years were included. The overall SFCT (mean ± SD) based on manual segmentation was 216.9 ± 82.7 µm with Triton DRI-OCT and 239.3 ± 84.3 µm with PLEX Elite 9000. ICC values demonstrated excellent agreement between AI-automated and manual segmented SFCT measurements (PLEX Elite 9000: ICC = 0.937, 95% CI: 0.922 to 0.949, P < 0.001; Triton DRI-OCT: ICC = 0.887, 95% CI: 0.608 to 0.950, P < 0.001). For PLEX Elite 9000, manual segmented measurements were generally thicker when compared to AI-automated segmented measurements, with a fixed bias of 6.3 µm (95% CI: 3.8 to 8.9, P < 0.001) and proportional bias of 0.120 (P < 0.001). On the other hand, manual segmented measurements were comparatively thinner than AI-automated segmented measurements for Triton DRI-OCT, with a fixed bias of - 26.7 µm (95% CI: - 29.7 to - 23.7, P < 0.001) and proportional bias of - 0.090 (P < 0.001). CONCLUSION: We observed an excellent agreement in choroidal segmentation measurements when comparing manual with AI-automated techniques, using images from two SS-OCT systems. Given its edge over manual segmentation, automated segmentation may potentially emerge as the primary method of choroidal thickness measurement in the future.

Pathologic myopia: advances in imaging and the potential role of artificial intelligence.

Pathologic myopia is a severe form of myopia that can lead to permanent visual impairment. The recent global increase in the prevalence of myopia has been projected to lead to a higher incidence of pathologic myopia in the future. Thus, imaging myopic eyes to detect early pathological changes, or predict myopia progression to allow for early intervention, has become a key priority. Recent advances in optical coherence tomography (OCT) have contributed to the new grading system for myopic maculopathy and myopic traction maculopathy, which may improve phenotyping and thus, clinical management. Widefield fundus and OCT imaging has improved the detection of posterior staphyloma. Non-invasive OCT angiography has enabled depth-resolved imaging for myopic choroidal neovascularisation. Artificial intelligence (AI) has shown great performance in detecting pathologic myopia and the identification of myopia-associated complications. These advances in imaging with adjunctive AI analysis may lead to improvements in monitoring disease progression or guiding treatments. In this review, we provide an update on the classification of pathologic myopia, how imaging has improved clinical evaluation and management of myopia-associated complications, and the recent development of AI algorithms to aid the detection and classification of pathologic myopia.

Quantitative assessment of the choroidal vasculature in myopic macular degeneration with optical coherence tomographic angiography.

Background: To assess and compare choroidal morphometric vascular parameters, using optical coherence tomographic angiography (OCTA), in highly myopic adults with and without myopic macular degeneration (MMD). Methods: This is a clinic-based observational study of 148 eyes with axial length (AL) ≥25mm, enrolled from the high myopia clinic of the Singapore National Eye Centre. MMD was graded from fundus photographs. Swept source OCT (SS-OCT) and OCTA were performed and assessed for choroidal layer thickness (CT) and choroidal vasculature (choroidal vessel density (CVD), choroidal branch area (CBA) and mean choroidal vessel width (MCVW)) in the different choroidal layers (overall choroidal layer (CL), medium-vessel choroidal layer (MVCL), large-vessel choroidal layer (LVCL)). Results: CTCL (r=-0.58, p<0.001), CTMVCL (r=-0.22, p=0.04), MCVWCL (r=-0.58, p<0.001), and CVDCL (r=-0.19, p=0.02) were negatively correlated with AL, while CBACL (r=0.61, p<0.001) was positively correlated. Compared to eyes with no MMD, eyes with MMD2 had lower CTCL (120.37±47.18µm vs 218.33±92.70µm, p<0.001), CTMVCL (70.57±15.28µm vs 85.32±23.71µm, p=0.04), CTLVCL (101.65±25.36µm vs 154.55±68.41µm, p=0.001) and greater CVDCL (71.10±3.97% vs 66.97±3.63%, p<0.001), CVDMVCL (66.96±2.35% vs 65.06±2.69%, p=0.002), CVDLVCL (68.36±2.56% vs 66.58±2.88%, p=0.012), MCVWMVCL (6.14±0.34µm vs 5.90±0.35µm, p=0.007), and CBACL (12.69±1.38% vs 11.34±1.18%, p<0.001). After adjusting for age, thicker CTCL (odds ratio (OR) 0.98, 95% confidence interval (CI) 0.97-0.99, p<0.001), CTMVCL (OR 0.97 (0.94-0.99), p=0.002) and CTLVCL (OR 0.97 (0.96-0.98, p<0.001) were significantly associated with lower odds of MMD2, while increased CVDCL (OR 1.37 (1.20-1.55), p<0.001), CVDMVCL (OR 1.39 (1.12-1.73), p=0.003), CVDLVCL (OR 1.31 (1.07-1.60), p=0.009), CBACL (OR 2.19 (1.55-3.08), p<0.001) and MCVWMVCL (OR 6.97 (1.59-30.51), p=0.01) was significantly associated with higher odds of MMD2. Conclusion: Decrease in choroidal vessel width, density and thickness, and an increase in vascular branching were observed in eyes with long AL. A thinner and denser choroid with greater branching area and vessel width, which may all be signs of hypoxia, were associated with greater odds of MMD2.

Predictors of myopic macular degeneration in a 12-year longitudinal study of Singapore adults with myopia.

PURPOSE: To investigate the predictive factors for myopic macular degeneration (MMD) and progression in adults with myopia. METHODS: We examined 828 Malay and Indian adults (1579 myopic eyes) with myopia (spherical equivalent (SE) ≤-0.5 dioptres) at baseline who participated in both baseline and 12-year follow-up visits of the Singapore Malay Eye Study and the Singapore Indian Eye Study. Eye examinations, including subjective refraction and axial length (AL) measurements, were performed. MMD was graded from fundus photographs following the Meta-Analysis for Pathologic Myopia classification. The predictive factors for MMD development and progression were assessed in adults without and with MMD at baseline, respectively as risk ratios (RR) using multivariable modified Poisson regression models. The receiver operating characteristic curve was used to visualise the performance of the predictive models for the development of MMD, with performance quantified by the area under the curve (AUC). RESULTS: The 12-year cumulative MMD incidence was 10.3% (95% CI 8.9% to 12.0%) among 1504 myopic eyes without MMD at baseline. Tessellated fundus was a major predictor of MMD (RR=2.50, p<0.001), among other factors including age, worse SE and longer AL (all p<0.001). The AUC for prediction of MMD development was found to be 0.78 (95% CI 0.76 to 0.80) for tessellated fundus and increased significantly to an AUC of 0.86 (95% CI 0.84 to 0.88) with the combination of tessellated fundus with age, race, gender and SE (p<0.001). Older age (p=0.02), worse SE (p<0.001) and longer AL (p<0.001) were found to be predictors of MMD progression. CONCLUSIONS: In adults with myopia without MMD, tessellated fundus, age, SE and AL had good predictive value for incident MMD. In adults with MMD, 1 in 10 eyes experienced progression over the same period. Older age, more severe myopia and longer AL were independent risk factors for progression.

Identifying Content for an Item Bank to Measure the Quality-of-Life Impact of Myopia Refractive Interventions.

Purpose: To report on the content generation and item refinement phases for a myopia refractive intervention-specific quality-of-life (QoL) item bank that will be operationalized using computerized adaptive testing. Methods: Myopia refractive intervention-specific QoL domains and items were generated from (1) a literature search of existing refractive-intervention QoL questionnaires; (2) semistructured interviews with myopic patients corrected using spectacles, contact lenses and/or refractive surgery (n = 32); (3) and myopia experts (n = 9) recruited from the Singapore National Eye Centre. After a thematic analysis, items were systematically refined and tested using cognitive interviews with 24 additional patients with corrected myopia. Results: Of the 32 participants with myopia interviewed (mean ± standard deviation age, 35.6 ± 9.0 years; 71.9% female; 78.1% Chinese), 12 (37.5%) wore spectacles, 7 (21.9%) used contact lenses, and 20 (62.5%) had undergone laser refractive surgery. Initially, 912 items within 7 independent QoL domains were identified. After refinement, 204 items were retained, including those relating to mobility challenges and work-related difficulties that are not well-represented in current refractive intervention-specific questionnaires. Conclusions: Through a rigorous item generation and selection process, we have developed a 204-item and 7-domain myopia refractive intervention-specific item bank that will now undergo rigorous psychometric testing to generate item calibrations for the validation of a novel computerized adaptive testing instrument designed for use in research and routine clinical practice. Translational Relevance: Once psychometrically validated and operationalized using computerized adaptive testing, this myopia refractive intervention-specific instrument will enable researchers and clinicians to quickly and comprehensively assess the impact of myopic refractive interventions across seven QoL domains.

Deep learning system to predict the 5-year risk of high myopia using fundus imaging in children.

Our study aims to identify children at risk of developing high myopia for timely assessment and intervention, preventing myopia progression and complications in adulthood through the development of a deep learning system (DLS). Using a school-based cohort in Singapore comprising of 998 children (aged 6-12 years old), we train and perform primary validation of the DLS using 7456 baseline fundus images of 1878 eyes; with external validation using an independent test dataset of 821 baseline fundus images of 189 eyes together with clinical data (age, gender, race, parental myopia, and baseline spherical equivalent (SE)). We derive three distinct algorithms - image, clinical and mix (image + clinical) models to predict high myopia development (SE ≤ -6.00 diopter) during teenage years (5 years later, age 11-17). Model performance is evaluated using area under the receiver operating curve (AUC). Our image models (Primary dataset AUC 0.93-0.95; Test dataset 0.91-0.93), clinical models (Primary dataset AUC 0.90-0.97; Test dataset 0.93-0.94) and mixed (image + clinical) models (Primary dataset AUC 0.97; Test dataset 0.97-0.98) achieve clinically acceptable performance. The addition of 1 year SE progression variable has minimal impact on the DLS performance (clinical model AUC 0.98 versus 0.97 in primary dataset, 0.97 versus 0.94 in test dataset; mixed model AUC 0.99 versus 0.97 in primary dataset, 0.95 versus 0.98 in test dataset). Thus, our DLS allows prediction of the development of high myopia by teenage years amongst school-going children. This has potential utility as a clinical-decision support tool to identify "at-risk" children for early intervention.