Epidemiological insights into epiretinal membranes using optical coherence tomography: the Singapore Epidemiology of Eye Diseases Study-2.

To investigate morphological variations in the macular area with optical coherence tomography (OCT) after vitrectomy for diabetic fibrovascular proliferation. We reviewed 108 cases using OCT 7-15 months after vitrectomy. Of these, 32 received OCT within 3 months postoperatively. Morphological variations were categorized and correlated with visual outcome. Only 24 cases (21.4%) had no obvious abnormalities. The most frequent findings were epiretinal membrane (52.8%), macular thickening (37.0%) and macular cysts (28.7%). Multivariate regression showed that diffuse macular thickening, loss of foveal depression and diffuse retinal thinning were significantly associated with poor visual acuity. Sequential OCT (< 3 and >or= 7 months) revealed that epiretinal membrane and oedema outside of fovea changed significantly between two examinations. OCT may identify diverse morphological changes in the macular area after diabetic vitrectomy for fibrovascular proliferation. Macular appearance may change over time, and certain types of morphological changes may be associated with poor visual function.

To assess epiretinal membrane (ERM) formation, severity, and the associated risk factors after scleral buckling using en face optical coherence tomography (OCT) images. Medical records of 61 consecutive patients (66 eyes) with rhegmatogenous retinal detachment who underwent scleral buckling were retrospectively reviewed. Posterior vitreous detachment (PVD) was determined based on B-scan OCT images. En face OCT images were used to visualize the ERM and retinal folds. ERM formation was identified by comparing en face images pre- and post-surgery. The maximum depth of the retinal folds (MDRF) was measured using en face imaging to objectively assess traction strength. ERM formation occurred in 15 (22.7%) eyes at the final visit; the foveal pit was preserved in all cases. Parafoveal retinal folds were present in 5 (7.6%) eyes, with a mean MDRF of 21.8 ± 12.6µm. No significant difference was observed in best-corrected visual acuity (logarithm of the minimal angle of resolution) between the ERM formation (-0.019 ± 0.128) and non-ERM formation (-0.001 ± 0.213) groups at the final visit (P = 0.593; Mann-Whitney U test). Multivariate logistic regression analysis revealed that older age and the presence of PVD were significant risk factors for ERM formation (odds ratio 1.07, 95% confidence interval 1.01-1.14, P = 0.032; odds ratio 5.26, 95% confidence interval 1.06-26.10, P = 0.042; respectively). ERM occurred in 22.7% of cases but was mild and did not affect visual acuity. Older age and the presence of PVD are risk factors for ERM formation.

High-Definition and 3-dimensional Imaging of Macular Pathologies with High-speed Ultrahigh-Resolution Optical Coherence Tomography

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Epiretinal membrane fragments: the origin of recurrent membranes after epiretinal membrane peeling

To examine prevalence and risk factors of epiretinal membrane (ERM) in a large, contemporary, multiethnic Asian population. Combined analysis of three population-based studies of eye diseases, with a total of 9799 Chinese, Malays and Indians residing in the general communities of Singapore. A comprehensive ophthalmic examination, interviews and laboratory blood tests were performed to assess potential risk factors. Digital retinal photographs were used to assess ERM according to a standardised protocol. ERM was classified into cellophane macular reflex (CMR) and/or preretinal macular fibrosis (PMF), and also as primary or secondary (in eyes with other retinal pathology or a history of cataract surgery). The age-standardised and ethnicity-standardised prevalence was 12.1% for any ERM, 6.8% for CMR, 6.7% for PMF and 2.8% for bilateral ERM. ERM prevalence was higher in Chinese (13.0%) compared with Malays (7.9%) or Indians (8.7%). In multivariate analysis, significant factors associated with primary ERM were older age (OR 1.08 per year increase; p<0.01), Chinese ethnicity (OR 1.60 vs Indians; p<0.01; OR 1.39 vs Malays; p<0.01), smoking (OR 0.70; p=0.01), longer axial length (OR 1.07 per mm increase; p=0.03) and cataract (OR 0.64; p<0.01). Significant factors independently associated with secondary ERM were older age (OR 1.05; p<0.01), cataract surgery (OR 10.6; p<0.01) and diabetic retinopathy (OR 2.48; p<0.01). ERM is common in Asians, particularly among Chinese. Older age is the most consistent risk factor for any ERM, and previous cataract surgery and diabetic retinopathy are the strongest risk factors for secondary ERM.

Three-dimensional printing using open source software and JPEG images from optical coherence tomography of an epiretinal membrane patient.

Macular oedema is a common complication and vision-limiting factor in uveitis. The aim of this study was to compare retinal thickness as measured by optical coherence tomography and photoreceptor function as measured by fundus-related microperimetry with respect to their correlation with visual acuity. Prospective observational monocentre study. Thirty-one patients (53 eyes) with endogenous uveitis and fluorescein angiographically confirmed macular oedema were evaluated. Foveal thickness was analysed using spectral-domain (Spectralis(TM) ; Heidelberg Engineering, Heidelberg, Germany) OCT and retinal sensitivity was assessed using fundus-related microperimetry (MP1; Nidek Technologies, Padova, Italy). All findings were correlated with best-corrected visual acuity (BCVA). Foveal thickness was correlated with BCVA [p = 0.005, r = 0.38, 95% confidence interval (CI) 0.12-0.59]. For microperimetry measurements, a negative correlation with logMAR visual acuity was found. Fixation abnormalities were not associated with poor visual acuity, increased foveal thickness or retinal sensitivity. In eyes with cystoid changes in the outer plexiform and inner nuclear layer, foveal thickness was increased (p < 0.0001). Epiretinal membrane formation was present in 70%. In these eyes, foveal thickness was significantly increased (p = 0.003) and visual acuity was worse (p = 0.08). Foveal thickness and fundus-related microperimetry were correlated with visual acuity. Cystoid changes in the outer plexiform and inner nuclear layer and the presence of epiretinal membrane were associated with poor visual acuity. Fixation abnormalities were not associated with poor visual acuity.

BackgroundTo compare imaging modalities for visualizing primary epiretinal membrane (ERM) with each other and with intraoperative digital images (IDI) after blue staining.MethodsThe records of consecutive patients operated for primary ERM over a 12-month period were retrospectively reviewed. Preoperative imaging included color fundus photography (CFP), En Face spectral-domain optical coherence tomography (OCT), 45° infrared- (IR) and blue-reflectance (BR) scanning laser ophthalmoscopy. All images were qualitatively analyzed and scored from 0–4 according to the ability to visualize ERM details (0 = no visible ERM or vessel contraction, 1 = vessel contraction, 2 = retinal folds, 3 = ERM limits, 4 = elevated ERM edge). The preoperative ERM morphology was then compared to that seen on the IDI acquired after 1-min blue dye staining when available.ResultsSeventy eyes were included. The highest score for ERM visualization was obtained on BR and En Face OCT. A score of 3 or 4 was obtained in 68.5%, 62.1%, 17.9% and 13.6% of cases on En Face OCT, BR, CFP and IR images, respectively. IDI were available for 20 eyes, and showed a similar ERM morphology compared to preoperative images in most cases: a negative staining pattern corresponded to a plaque on En face OCT in 91% of eyes. However, IDI failed to show the ERM edges in 37.5% of cases.ConclusionERM morphology was better visualized preoperatively by BR and En Face OCT, in a similar way to the IDI after staining. Future intraoperative visualization systems could integrate both imaging modalities overlaid with the IDI for guiding ERM removal instead of staining.

PurposeTo verify the correlation between the full-macular and the ganglion cell complex (GCC) thickness measurements and retinal sensitivity (RS) assessed by microperimetry (MP) 6 months after surgical peeling for idiopathic epiretinal membrane (ERM).MethodsForty-three were submitted to pars-plana posterior vitrectomy (PPV) with concomitant peeling of internal limiting membrane (ILM) for idiopathic ERM treatment. Best-corrected visual acuity (BCVA) and 3D volumetric high-definition optical coherence tomography (OCT) imaging were preoperatively acquired. Six months after the surgery, BCVA, OCT imaging, and RS measured by MP were assessed. For the OCT parameters, we analyzed both the full-macular and the ganglion cell layer complex (GCC) thicknesses. The MP parameters tested were 44 points covering 20 central degrees (6 mm), with direct correspondence with the nine sectors of the OCT-ETDRS map. This approach enables the direct topographic correlation between the structure and functional measurements. The OCT and MP exam measurements were also performed in 43 eyes of age-matched healthy controls. Correlations between BCVA, RS, and OCT parameters were examined.Results All patients exhibited a substantial improvement in visual acuity following surgery. The RS parameters were significantly lower in patients compared to the controls. The full-macular thickness measurements were thicker than controls preoperatively and significantly reduced postoperatively; however, remaining significantly higher than controls, in the 4 inner sectors, at the fovea and for the average macular thickness. Preoperative GCC measurements were higher than those in controls. There was a significant reduction in GCC thickness in all sectors postoperatively, especially in the outer sectors, as well as in the average macular thickness. A positive correlation was found between full-macular and GCC thickness and RS postoperatively in several sectors.ConclusionsOur results demonstrate that ERM peeling can improve visual acuity in the postoperative period. However, RS may not fully restore, remaining significantly lower when compared to the controls. Both full-macular and GCC thickness measurements were reduced 6 months after surgery. However, significant thinning of the GCC thickness was observed when compared to the normal control eyes, indicating the occurrence of some degree of ganglion cell layer atrophy. We have demonstrated significant correlations among various OCT thickness parameters, particularly for GCC measurements. We believe that GCC integrity may play an important role in visual function after ERM surgery, and that MP may help better understand the correlations between structural and functional findings following ERM surgery.

Optimizing optical coherence tomography and histopathology correlation in retinal imaging

Purpose: To describe OCT findings in pediatric uveitis patients and analyze visual acuity changes over time. Methods: A retrospective chart review of pediatric patients (0 to 18 years old) seen at the Emory Eye Center between 2008 and June 2020 with a diagnosis of uveitis and OCT imaging available was conducted. Data collected included demographic data, uveitis etiology, anatomical uveitis location, best-corrected visual acuity (BCVA), findings on OCT, and treatment. Results: There were 204 patients and 327 eyes with a diagnosis of pediatric uveitis and at least one OCT on record. The average age was 11.5 years with 57% females (116), 43% Black (87) and 33% Caucasian (68). 137 (67%) patients had bilateral uveitis with the majority, 194 (95%), with a non-infectious etiology. Anatomical location of uveitis was anterior, intermediate, anterior/intermediate, posterior, or panuveitis in 42%, 24%, 9%, 10%, and 15% respectively. At baseline on OCT, there were 222 normal eyes, 19 eyes with an epiretinal membrane (ERM), 53 eyes with macular edema, 14 eyes with both macular edema and ERM, and 19 eyes with subretinal fibrosis. On mixed model analysis controlling for the correlation that exists between eyes of the same subject, the worst initial BCVA was seen in eyes with epiretinal membrane and macular edema, followed by macular edema eyes, subretinal fibrosis, and eyes with an ERM with a logMAR BCVA of 0.95, 0.75, 0.73, and 0.50 respectively (p<0.0001). Notably, with most abnormal OCT findings, BCVA improved over 24 months except for ERM eyes, which showed a logMAR BCVA change of 0.50 to 0.60 (p<0.0001). In a sub-analysis of patients with macular edema with or without subretinal fluid (SRF), there was no difference between baseline clinical characteristics or BCVA in patients who had SRF. Conclusions: OCT imaging in pediatric uveitis is important for diagnosis and monitoring progression of sight- threatening complications. Pediatric uveitis cases show a high proportion of bilateral involvement and prevalence of complications leading to worse BCVA, which demonstrates that prompt treatment and continued monitoring via OCT imaging can prevent ocular sequelae leading to blindness.

Singapore's ageing population is likely to see an increase in chronic eye conditions in the future. This study aimed to estimate the burden of eye diseases among resident Singaporeans stratified for age and ethnicity by 2040. Prevalence data on myopia, epiretinal membrane (ERM), retinal vein occlusion (RVO), age macular degeneration (AMD), diabetic retinopathy (DR), cataract, glaucoma and refractive error (RE) by age cohorts and educational attainment from the Singapore Epidemiology of Eye Diseases (SEED) study were applied to population estimates from the Singapore population model. All eye conditions are projected to increase by 2040. Myopia and RE will remain the most prevalent condition, at 2.393 million (2.32 to 2.41 million) cases, representing a 58% increase from 2015. It is followed by cataract and ERM, with 1.33 million (1.31 to 1.35 million), representing an 81% increase, and 0.54 million (0.53 to 0.549 million) cases representing a 97% increase, respectively. Eye conditions that will see the greatest increase from 2015 to 2040 in the Chinese are: DR (112%), glaucoma (100%) and ERM (91.4%). For Malays, DR (154%), ERM (136%), and cataract (122%) cases are expected to increase the most while for Indians, ERM (112%), AMD (101%), and cataract (87%) are estimated to increase the most in the same period. Results indicate that the burden for all eye diseases is expected to increase significantly into the future, but at different rates. These projections can facilitate the planning efforts of both policymakers and healthcare providers in the development and provision of infrastructure and resources to adequately meet the eye care needs of the population. By stratifying for age and ethnicity, high risk groups may be identified and targeted interventions may be implemented.

This study aimed to investigate morphological differences between idiopathic epiretinal membrane (ERM) and secondary ERM due to peripheral break (SEPB) and to identify clinical characteristics in eyes with SEPB to facilitate peripheral retinal examination. The retrospective cross-sectional study involved 93 consecutive eyes in 91 patients who underwent ERM removal surgery. Eyes were divided into two groups: the macular pucker group and the idiopathic ERM group. En-face Optical Coherence Tomography (OCT) images, fundus photographs, severity of metamorphopsia (M-score) and clinical characteristics of each group were compared. ERM extent and eccentricity (ratio of the shortest and longest distances from the foveal center to the boundary) were obtained through en-face OCT imaging. Fundus photographs were used to judge whether the membrane was turbid or not. Patients with SEPB were younger than patients with idiopathic ERM (61.3 ± 7.5 vs. 66.6 ± 8.3 years; p < 0.05). Preoperative M-score and myopic refractive error, axial length were also significantly higher in the macular pucker group than in the idiopathic ERM group (all p < 0.05). There was no difference in ERM extent between the two groups. The incidence of ERM eccentricity was 23 of the 34 eyes (67.6%) in the SEPB group and 26 of the 59 eyes (44.1%) in the idiopathic ERM group (p < 0.05). The incidence of turbid ERM was 18 of the 34 eyes (52.9%) in the SEPB group and 10 of the 59 eyes (16.9%) in the idiopathic ERM group (p < 0.01). The SEPB group, compared with the idiopathic ERM group, tended to have eccentric, turbid ERM at a younger age and with more severe metamorphopsia and myopic refractive error.

To assess prevalence and associations of epiretinal membranes (ERMs) in a general population. In participants of the population-based Beijing Eye Study, we assessed macular volume optical coherence tomographic (OCT) scans for ERMs. The study included 1351 eyes (914 participants) (age: 64.7±9.8 years; range: 50-91 years). ERMs were detected in 80 eyes (5.9%; 95% CI 4.9% to 6.9%) of 60 participants (6.6%; 95% CI 5.1% to 8.1%), with ERMs without retinal surface wrinkling in 34 (2.5%) eyes, ERMs with retinal surface wrinkling and normal fovea contour in 16 (1.2%) eyes, ERMs with reduced foveal depth in 20 (1.5%) eyes, ERMs with complete foveal flattening in 6 (0.4%) eyes and ERMs with foveal elevation in 4 (0.2%) eyes. Hyper-reflective epiretinal dots (HEDs) were detected in 114 (8.4%) eyes. Higher ERM prevalence was associated (multivariable analysis) with higher stage of posterior vitreous detachment (PVD) (OR: 1.81; 95% CI 1.34 to 2.45; p<0.001), older age (OR: 1.05; 95% CI 1.01 to 1.09; p=0.002), higher prevalence of HEDs (OR: 9.18; 95% CI 4.85 to 17.4; p<0.001) and worse best corrected visual acuity (BCVA) (OR: 2.75; 95% CI 1.04 to 7.30; p=0.04), but not with axial length (p=0.69) or pseudophakia (p=0.98). Out of 746 eyes without PVD, 3 (0.4%) eyes had ERMs (without retinal surface wrinkling) and 9 (1.2%) eyes showed HEDs. Higher ERM stage increased with higher PVD stage (beta: 0.32; p<0.001), older age (beta: 0.11; p=0.006) and worse BCVA (beta: 0.07; p=0.04), but not with axial length (p=0.75) or pseudophakia (p=0.71). As measured by OCT, ERM prevalence was mainly associated with PVD and to a minor degree with older age and worse BCVA, while longer axial length, pseudophakia or ocular diseases such as age-related macular disease and glaucoma were not related to prevalence and stage of ERMs.