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1.
Eye Vis (Lond) ; 11(1): 21, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38831465

ABSTRACT

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.

2.
Br J Ophthalmol ; 108(3): 411-416, 2024 02 21.
Article in English | MEDLINE | ID: mdl-36690422

ABSTRACT

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.


Subject(s)
Choroidal Neovascularization , Macular Degeneration , Myopia, Degenerative , Humans , Middle Aged , Aged , Cross-Sectional Studies , Myopia, Degenerative/complications , Myopia, Degenerative/diagnosis , Myopia, Degenerative/epidemiology , Refraction, Ocular , Vision Disorders/pathology , Macular Degeneration/complications , Choroidal Neovascularization/pathology , Tomography, Optical Coherence , Axial Length, Eye/pathology
3.
Sci Adv ; 9(39): eadg1936, 2023 09 29.
Article in English | MEDLINE | ID: mdl-37774033

ABSTRACT

Human pluripotent stem cells (hPSCs) are of fundamental relevance in regenerative medicine. Naïve hPSCs hold promise to overcome some of the limitations of conventional (primed) hPSCs, including recurrent epigenetic anomalies. Naïve-to-primed transition (capacitation) follows transcriptional dynamics of human embryonic epiblast and is necessary for somatic differentiation from naïve hPSCs. We found that capacitated hPSCs are transcriptionally closer to postimplantation epiblast than conventional hPSCs. This prompted us to comprehensively study epigenetic and related transcriptional changes during capacitation. Our results show that CpG islands, gene regulatory elements, and retrotransposons are hotspots of epigenetic dynamics during capacitation and indicate possible distinct roles of specific epigenetic modifications in gene expression control between naïve and primed hPSCs. Unexpectedly, PRC2 activity appeared to be dispensable for the capacitation. We find that capacitated hPSCs acquire an epigenetic state similar to conventional hPSCs. Significantly, however, the X chromosome erosion frequently observed in conventional female hPSCs is reversed by resetting and subsequent capacitation.


Subject(s)
Pluripotent Stem Cells , Humans , Female , Cell Differentiation/genetics , Embryo, Mammalian , Epigenesis, Genetic
4.
Transl Vis Sci Technol ; 12(5): 27, 2023 05 01.
Article in English | MEDLINE | ID: mdl-37227748

ABSTRACT

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.


Subject(s)
Myopia , Quality of Life , Humans , Female , Adult , Male , Quality of Life/psychology , Refraction, Ocular , Myopia/diagnosis , Myopia/therapy , Vision Tests , Surveys and Questionnaires
5.
Clin Exp Ophthalmol ; 51(6): 585-597, 2023 08.
Article in English | MEDLINE | ID: mdl-37170410

ABSTRACT

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.


Subject(s)
COVID-19 , Ophthalmologists , Retinal Detachment , Humans , Scleral Buckling/methods , Vitrectomy/methods , Pandemics , Treatment Outcome , Visual Acuity , COVID-19/epidemiology , Retinal Detachment/epidemiology , Retinal Detachment/surgery , Asia/epidemiology , Retrospective Studies
6.
NPJ Digit Med ; 6(1): 10, 2023 Jan 26.
Article in English | MEDLINE | ID: mdl-36702878

ABSTRACT

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.

7.
Br J Ophthalmol ; 107(5): 600-606, 2023 05.
Article in English | MEDLINE | ID: mdl-35288438

ABSTRACT

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.


Subject(s)
Macular Degeneration , Myopia, Degenerative , Humans , Myopia, Degenerative/diagnostic imaging , Artificial Intelligence , Tomography, Optical Coherence/methods , Vision Disorders/etiology , Fundus Oculi , Macular Degeneration/complications , Retrospective Studies
8.
Br J Ophthalmol ; 107(9): 1363-1368, 2023 09.
Article in English | MEDLINE | ID: mdl-35534177

ABSTRACT

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.


Subject(s)
Macular Degeneration , Myopia, Degenerative , Humans , Adult , Longitudinal Studies , Visual Acuity , Singapore/epidemiology , Myopia, Degenerative/diagnosis , Myopia, Degenerative/epidemiology , Myopia, Degenerative/complications , Macular Degeneration/diagnosis , Macular Degeneration/epidemiology , Macular Degeneration/etiology , Refraction, Ocular , Vision Disorders
9.
Genome Biol ; 23(1): 207, 2022 10 03.
Article in English | MEDLINE | ID: mdl-36192798

ABSTRACT

BACKGROUND: Histone lactylation has been recently described as a novel histone post-translational modification linking cellular metabolism to epigenetic regulation. RESULTS: Given the expected relevance of this modification and current limited knowledge of its function, we generate genome-wide datasets of H3K18la distribution in various in vitro and in vivo samples, including mouse embryonic stem cells, macrophages, adipocytes, and mouse and human skeletal muscle. We compare them to profiles of well-established histone modifications and gene expression patterns. Supervised and unsupervised bioinformatics analysis shows that global H3K18la distribution resembles H3K27ac, although we also find notable differences. H3K18la marks active CpG island-containing promoters of highly expressed genes across most tissues assessed, including many housekeeping genes, and positively correlates with H3K27ac and H3K4me3 as well as with gene expression. In addition, H3K18la is enriched at active enhancers that lie in proximity to genes that are functionally important for the respective tissue. CONCLUSIONS: Overall, our data suggests that H3K18la is not only a marker for active promoters, but also a mark of tissue specific active enhancers.


Subject(s)
Enhancer Elements, Genetic , Histones , Animals , Epigenesis, Genetic , Histone Code , Histones/metabolism , Humans , Mice , Promoter Regions, Genetic
10.
Asia Pac J Ophthalmol (Phila) ; 11(5): 434-440, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-36102646

ABSTRACT

PURPOSE: To describe ophthalmology training experiences across the Asia-Pacific (APAC). DESIGN: Survey study. METHODS: We utilized an anonymous online survey, which was previously validated and conducted in Europe, through Young Ophthalmologist leaders from the national member societies of the Asia-Pacific Academy of Ophthalmology (APAO) from September 2019 to July 2021. Responses were based on a 5-point Likert scale (where applicable) and data were analyzed using Microsoft Excel. Our main outcome measures were differences between regions, that is, Southeast Asia (SEA) and Western Pacific (WP); and seniority, that is, trainees/junior ophthalmologists and senior ophthalmologists. RESULTS: We collated 130 responses representing 20 regions in the APAC region. The year of completion of ophthalmic training ranged from 1999 to 2024. The mean duration of training was 3.7±1.0 years. Most (98/130, 75%) indicated an interest for a common training standard across the APAC. Comparing SEA and WP trainees, both regions had similar working environments, but those in SEA reported significantly lower remuneration than their counterparts in WP ($600 vs $3000, P <0.05). WP trainees performed more phacoemulsification surgeries (76 WP vs 19 SEA), while SEA trainees conducted more manual small incision cataract surgeries (157 WP vs 1.5 SEA per duration of training). Senior ophthalmologists performed more cataract surgeries (210.9 senior ophthalmologists vs 40.1 junior ophthalmologists). Trainees had less confidence in medical competency areas such as interpreting an electroretinogram/visual evoked potential/electrooculogram (SEA=1.8, WP=2.1) and conducting an angiography (SEA=2.8, WP=3.4). CONCLUSIONS: Our study highlighted heterogeneity among ophthalmology training experiences in the APAC region, with the majority indicating an interest in a common training standard.


Subject(s)
Cataract , Eye Diseases , Internship and Residency , Ophthalmologists , Ophthalmology , Clinical Competence , Education, Medical, Graduate , Evoked Potentials, Visual , Eye Diseases/surgery , Humans , Ophthalmologists/education , Ophthalmology/education
11.
Polymers (Basel) ; 14(15)2022 Jul 25.
Article in English | MEDLINE | ID: mdl-35893969

ABSTRACT

The production of nanofibrous materials for soft tissue repair that resemble extracellular matrices (ECMs) is challenging. Electrospinning uniquely produces scaffolds resembling the ultrastructure of natural ECMs. Herein, electrospinning was used to fabricate Bombyx mori silk fibroin (SF) and SF/halloysite nanotube (HNT) composite scaffolds. Different HNT loadings were examined, but 1 wt% HNTs enhanced scaffold hydrophilicity and water uptake capacity without loss of mechanical strength. The inclusion of 1 wt% HNTs in SF scaffolds also increased the scaffold's thermal stability without altering the molecular structure of the SF, as revealed by thermogravimetric analyses and Fourier transform infrared spectroscopy (FTIR), respectively. SF/HNT 1 wt% composite scaffolds better supported the viability and spreading of 3T3 fibroblasts and the differentiation of C2C12 myoblasts into aligned myotubes. These scaffolds coated with decellularised ECM from 3T3 cells or primary human dermal fibroblasts (HDFs) supported the growth of primary human keratinocytes. However, SF/HNT 1 wt% composite scaffolds with HDF-derived ECM provided the best microenvironment, as on these, keratinocytes formed intact monolayers with an undifferentiated, basal cell phenotype. Our data indicate the merits of SF/HNT 1 wt% composite scaffolds for applications in soft tissue repair and the expansion of primary human keratinocytes for skin regeneration.

12.
Diagnostics (Basel) ; 12(6)2022 Jun 08.
Article in English | MEDLINE | ID: mdl-35741230

ABSTRACT

Advances in imaging with optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) technology, including the development of swept source OCT/OCTA, widefield or ultra-widefield systems, have greatly improved the understanding, diagnosis, and treatment of myopia and myopia-related complications. Anterior segment OCT is useful for imaging the anterior segment of myopes, providing the basis for implantable collamer lens optimization, or detecting intraocular lens decentration in high myopic patients. OCT has enhanced imaging of vitreous properties, and measurement of choroidal thickness in myopic eyes. Widefield OCT systems have greatly improved the visualization of peripheral retinal lesions and have enabled the evaluation of wide staphyloma and ocular curvature. Based on OCT imaging, a new classification system and guidelines for the management of myopic traction maculopathy have been proposed; different dome-shaped macula morphologies have been described; and myopia-related abnormalities in the optic nerve and peripapillary region have been demonstrated. OCTA can quantitatively evaluate the retinal microvasculature and choriocapillaris, which is useful for the early detection of myopic choroidal neovascularization and the evaluation of anti-vascular endothelial growth factor therapy in these patients. In addition, the application of artificial intelligence in OCT/OCTA imaging in myopia has achieved promising results.

13.
Drug Deliv Transl Res ; 12(1): 7-14, 2022 01.
Article in English | MEDLINE | ID: mdl-33569720

ABSTRACT

Liposomes as a drug delivery system may overcome the problems associated with non-compliance to eyedrops and inadequate control of inflammation after cataract surgery. We evaluated the safety and efficacy of a single subconjunctival injection of liposomal prednisolone phosphate (LPP) for the treatment of post-cataract surgery inflammation. This is a phase I/II, open-label non-comparative interventional trial of patients undergoing cataract surgery. All patients received a single injection of subconjunctival LPP intraoperatively. The primary outcome measure was the proportion of eyes with an anterior chamber cell count of 0 at postoperative month 1. Ocular and non-ocular adverse events, including elevated intraocular pressure, rebound iritis and pseudophakic macular edema were monitored. Five patients were enrolled in this study. The mean age was 66.6 ± 6.2 and 4 (80%) were male. The proportion of patients with AC cell grading of 0 was 0%, 80%, 80%, and 100% at day 1, week 1, month 1, and month 2 after cataract surgery, respectively. Mean laser flare photometry readings were significantly elevated at week 1 after cataract surgery (48.8 ± 18.9, p = 0.03) compared with baseline, decreasing to 25.8 ± 9.2 (p = 0.04) at month 1 and returned to baseline by month 2 (10.9 ± 5.1, p = 1.0). No ocular or non-ocular adverse events were observed. Liposomal prednisolone phosphate, administered as a single subconjunctival injection intraoperatively, can be a safe and effective treatment for post-cataract surgery inflammation. The delivery of steroids with a liposomal drug delivery system could potentially replace eyedrops as anti-inflammatory therapy following cataract surgery.


Subject(s)
Cataract , Aged , Anti-Inflammatory Agents/therapeutic use , Cataract/chemically induced , Drug Delivery Systems , Female , Humans , Liposomes , Male , Middle Aged
14.
Br J Ophthalmol ; 106(5): 681-688, 2022 05.
Article in English | MEDLINE | ID: mdl-33397658

ABSTRACT

PURPOSE: To quantify retinal and choriocapillaris (CC) microvasculature in highly myopic (HM) eyes with myopic macular degeneration (MMD) using swept-source optical coherence tomography angiography (SS-OCTA). METHODS: 162 HM eyes (spherical equivalent ≤ -6.0 dioptres or axial length (AL) ≥26.5 mm) from 98 participants were enrolled, including 60 eyes (37.0%) with tessellated fundus, 54 eyes (33.3%) with peripapillary diffuse chorioretinal atrophy (PDCA), 27 eyes (16.7%) with macular diffuse chorioretinal atrophy (MDCA) and 21 eyes (13.0%) with patchy or macular atrophy. PLEX Elite 9000 SS-OCTA was performed to obtain perfusion densities (PD) of the superficial and deep retinal capillary plexus, and CC signal voids (number, area and density). RESULTS: Retinal PD decreased with increasing severity of MMD. Multivariable analysis showed that after adjustment of age and other factors, retinal PD decreased significantly in eyes with longer AL (ß≤-0.51, p<0.001) and with an MMD severity of MDCA or worse (ß≤-1.63, p<0.001). Reduced retinal PD were significantly associated with worse vision (ß≤-0.01, p≤0.04). In terms of CC signal voids, multivariable analysis showed that longer AL (p<0.001), but not MMD severity (p≥0.12) was significantly associated with CC signal void changes in the earliest stage of MMD. CONCLUSION: We demonstrate significant OCTA alterations in the retina and CC in HM eyes with varying severities of MMD. In eyes with early-stage PDCA, lower retinal PD and more extensive CC signal voids are predominantly associated with increasing AL. In contrast, in eyes with MDCA or worse, MMD itself was associated with sparser retinal and CC circulation.


Subject(s)
Macular Degeneration , Myopia, Degenerative , Angiography , Atrophy , Choroid/pathology , Choroid Diseases , Fluorescein Angiography/methods , Humans , Macular Degeneration/complications , Microvessels , Myopia, Degenerative/complications , Myopia, Degenerative/diagnosis , Retina , Retinal Vessels/pathology , Tomography, Optical Coherence/methods
15.
Br J Ophthalmol ; 106(9): 1308-1312, 2022 09.
Article in English | MEDLINE | ID: mdl-33741583

ABSTRACT

BACKGROUND/AIMS: To explore if retinal findings are associated with COVID-19 infection. METHODS: In this prospective cross-sectional study, we recruited participants positive for COVID-19 by nasopharyngeal swab, with no medical history. Subjects underwent retinal imaging with an automated imaging device (3D OCT-1 Maestro, Topcon, Tokyo, Japan) to obtain colour fundus photographs (CFP) and optical coherence tomographic (OCT) scans of the macula. Data on personal biodata, medical history and vital signs were collected from electronic medical records. RESULTS: 108 patients were recruited. Mean age was 36.0±5.4 years. 41 (38.0%) had symptoms of acute respiratory infection (ARI) at presentation. Of 216 eyes, 25 (11.6%) had retinal signs-eight (3.7%) with microhaemorrhages, six (2.8%) with retinal vascular tortuosity and two (0.93%) with cotton wool spots (CWS). 11 eyes (5.1%) had hyper-reflective plaques in the ganglion cell-inner plexiform layer layer on OCT, of which two also had retinal signs visible on CFP (CWS and microhaemorrhage, respectively). There was no significant difference in the prevalence of retinal signs in symptomatic versus asymptomatic patients (12 (15.0%) vs 13 (9.6%), p=0.227). Patients with retinal signs were significantly more likely to have transiently elevated blood pressure than those without (p=0.03). CONCLUSION: One in nine had retinal microvascular signs on ocular imaging. These signs were observed even in asymptomatic patients with normal vital signs. These retinal microvascular signs may be related to underlying cardiovascular and thrombotic alternations associated with COVID-19 infection.


Subject(s)
COVID-19 , Macula Lutea , Adult , Cross-Sectional Studies , Humans , Prospective Studies , Tomography, Optical Coherence/methods
16.
Br J Ophthalmol ; 106(10): 1423-1428, 2022 10.
Article in English | MEDLINE | ID: mdl-33888462

ABSTRACT

AIMS: To characterise the association between visual field (VF) defects and myopic macular degeneration (MMD) in highly myopic adults without glaucoma. METHODS: Participants (n=106; 181 eyes) with high myopia (HM; spherical equivalent ≤-5.0 D or axial length (AL) ≥26 mm), after excluding glaucoma and glaucoma suspects, from the Singapore Epidemiology of Eye Diseases-HM study were included in this cross-sectional study. Humphrey VF (central 24-2 threshold), cup-disc ratio (CDR) and intraocular pressure (IOP) measurements were performed. Mean deviation (MD) and pattern SD (PSD), VF defects (normal or abnormal; p<0.05 in ≥3 non-edge contiguous locations) and pattern (eg, generalised sensitivity loss) were analysed. MMD presence was diagnosed from fundus photographs. Generalised estimating equations were used for analysing factors (MD, PSD, VF defects, CDR and IOP) associated with MMD. RESULTS: Mean age was 55.4±9.9 years and 51.9% were women (AL=26.7±1.1 mm). MMD eyes had lower MD (-3.8±2.9 dB vs -1.1±1.4 dB) and higher PSD (2.8±1.7 dB vs 1.7±0.6 dB). A higher percentage of MMD eyes (n=48) had abnormal VF (62.5% vs 28.6%; p<0.001) compared with no MMD (n=133 eyes). VF pattern in MMD eyes was significantly different from eyes without MMD (p=0.001) with greater generalised sensitivity loss (53.3% vs 10.5%) and arcuate defects (16.7% vs 10.5%). In multivariate analyses, MD (OR=1.52) and PSD (OR=1.67) were significantly (p=0.003) associated with MMD, but VF defects were not associated with MMD. CONCLUSION: Highly myopic adults with MMD may have VF loss when compared with highly myopic patients without MMD even in adults without glaucoma.


Subject(s)
Glaucoma , Macular Degeneration , Myopia, Degenerative , Optic Disk , Adult , Aged , Cross-Sectional Studies , Female , Humans , Intraocular Pressure , Macular Degeneration/complications , Macular Degeneration/diagnosis , Macular Degeneration/epidemiology , Male , Middle Aged , Myopia, Degenerative/complications , Myopia, Degenerative/diagnosis , Myopia, Degenerative/epidemiology , Singapore/epidemiology , Vision Disorders/diagnosis , Vision Disorders/epidemiology , Visual Field Tests , Visual Fields
17.
Retina ; 42(4): 669-678, 2022 04 01.
Article in English | MEDLINE | ID: mdl-34934033

ABSTRACT

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.


Subject(s)
Myopia , White Dot Syndromes , Aged , Atrophy , Fluorescein Angiography , Humans , Middle Aged , Multifocal Choroiditis , Myopia/complications , Myopia/diagnosis , Myopia/epidemiology , Prevalence , Retrospective Studies , Tomography, Optical Coherence/methods , Vision Disorders
18.
Front Med (Lausanne) ; 8: 718724, 2021.
Article in English | MEDLINE | ID: mdl-34926485

ABSTRACT

Myopia is one of the leading causes of visual impairment globally. Despite increasing prevalence and incidence, the associated cost of treatment remains unclear. Health care spending is a major concern in many countries and understanding the cost of myopia correction is the first step eluding to the overall cost of myopia treatment. As cost of treatment will reduce the burden of cost of illness, this will aid in future cost-benefit analysis and the allocation of healthcare resources, including considerations in integrating eye care (refractive correction with spectacles) into universal health coverage (UHC). We performed a systematic review to determine the economic costs of myopia correction. However, there were few studies for direct comparison. Costs related to myopia correction were mainly direct with few indirect costs. Annual prevalence-based direct costs for myopia ranged from $14-26 (USA), $56 (Iran) and $199 (Singapore) per capita, respectively (population: 274.63 million, 75.15 million and 3.79 million, respectively). Annually, the direct costs of contact lens were $198.30-$378.10 while spectacles and refractive surgeries were $342.50 and $19.10, respectively. This review provides an insight to the cost of myopia correction. Myopia costs are high from nation-wide perspectives because of the high prevalence of myopia, with contact lenses being the more expensive option. Without further interventions, the burden of illness of myopia will increase substantially with the projected increase in prevalence worldwide. Future studies will be necessary to generate more homogenous cost data and provide a complete picture of the global economic cost of myopia.

19.
Clin Ophthalmol ; 15: 4455-4465, 2021.
Article in English | MEDLINE | ID: mdl-34819717

ABSTRACT

PURPOSE: To investigate features of the steady-state pattern electroretinogram (ssPERG) in subjects with glaucoma (G), high myopia (HM; spherical equivalent ≤-6D) and glaucoma with high myopia (GHM). PATIENTS AND METHODS: Our study included 48 participants divided into 3 groups (G, HM, and GHM) who each underwent monocular ssPERG testing with Diopsys NOVA PERG protocols. The ConStim protocol detects distinct topographic patterns of dysfunction 16° and 24° around the central macula. MagD is the amplitude of the average signal and MagD/Mag ratio indicates the consistency of the response. ssPERG indices were compared between groups and correlated with functional (ie, visual field mean deviation (VFMD)) and structural (ie, average retinal nerve fibre layer (RNFL) thickness; Cirrus optical coherence tomography) features. RESULTS: Participants had an average age of 59.4±7.6 years. Mean Humphrey VFMD was -14.22 ± 2.88dB, -2.62 ± 1.18dB and -12.80 ± 2.60dB for G, HM and GHM groups, respectively. Mean RNFL thickness was 63.0 ± 8.20µm, 69.5 ± 15.7µm and 60.6 ± 5.0µm for G, HM and GHM groups, respectively. For the 24° setting, no significant differences were noted for any of the parameters. For the 16° setting, MagD was lower in the GHM group compared to the HM group (0.29µV vs 0.52µV; p = 0.02). Significant differences were noted for the MagD/Mag ratio between HM and G groups (0.58 vs 0.40; p = 0.02) and between HM and GHM groups (0.58 vs 0.35; p = 0.002). There were positive correlations between both MagD 16° and MagD/Mag ratio 16° with VFMD (correlation coefficient [r]=0.37, p = 0.009; and r = 0.44, p = 0.002, respectively) and RNFL (r = 0.43, p = 0.002; and r = 0.48, p = 0.001, respectively). CONCLUSION: MagD/Mag ratio at 16° was significantly lower in glaucomatous eyes (with or without high myopia) compared to those with high myopia without glaucoma, suggesting that glaucoma has a distinct impact on MagD/Mag ratio at 16° irrespective of the presence of myopia.

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