Long-term Visual and Anatomical Outcome after Surgical Management of Epiretinal Membrane.

OBJECTIVE: To assess the functional and surgical long-term outcomes following epiretinal membrane surgery. STUDY DESIGN: Case series. PLACE AND DURATION OF STUDY: Layton Rahmatulla Benevolent Trust Tertiary Care Eye Hospital, Karachi, from January 2016 to December 2020. METHODOLOGY: A medical record review was carried out of patients, who had undergone surgical management of ERM and had presented for follow-up for at least three years. Best corrected visual acuity (BCVA) and Optical Coherence Tomography (OCT) parameter [(integrity of ellipsoid zone (EZ)] was evaluated. BCVA, using Snellen's chart, is performed routinely on each visit, which was converted to logMAR chart for analysis in this study. OCT was also performed to evaluate the integrity of outer retinal layers using Heidelberg OCT. RESULTS: Sixty-five eyes of 54 patients were included in the study, including 41 eyes of 36 men (63%) and 24 eyes of 18 women (37%). Mean age was 46.2 ± 8.9 years. The mean BCVA significantly improved from 0.88 ± 0.28 logMAR (6/45 Snellen) preoperatively to 0.64 ± 0.21 (6/27) at the end of first year (p <0.001), which improved to 0.54 ± 0.19 (6/21) at the end of second year, and 0.53 ± 0.20 (6/20) after three years of follow-up. The post-op vision at three years was stratified according to the integrity of EZ on OCT performed at the same follow-up; and a significant difference was observed. EZ was intact in 52 eyes with a mean BCVA of 0.49 ± 0.16 logMAR (6/18 Snellen); while it was found disrupted in 13 eyes, where the BCVA was 0.68 ± 0.26 (6/29). CONCLUSION: Anatomically intact outer retinal layer significantly correlated with improved BCVA. Key Words: Epiretinal membrane, Optical coherence tomograghy, Best corrected visual acuity.

Treatment of Chronic Large and Persistent Macular Hole by a new technique in a Tertiary Care Hospital.

OBJECTIVE: To assess the anatomical and functional outcomes of treating chronic persistent large macular hole by macular hole hydrodissection technique in a tertiary eye care hospital. METHODS: This interventional case series study was conducted in the Vitreoretinal department of LRBT Tertiary Teaching Eye Hospital, Karachi, from October 2017 to March 2018, with follow-ups till February 2019. The study included eighteen cases of chronic (symptoms of loss of central vision ≥ 2years), persistent (previously failed macular hole surgery), large (aperture diameter of ≥ 400µm) macular hole. Out of the eighteen patients, eight (44.4%) were males and ten (55.6%) were females. All operated patients underwent macular hole hydrodissection by balanced salt solution using a silicone soft tip extrusion cannula. Patients were followed up post operatively to assess post-operative complications and surgical results. RESULTS: Among eighteen patients with a mean aperture diameter of 477.1±102.9 µm and basal diameter of 849.4± 92.6µm, complete anatomical closure was achieved in sixteen (88.8%). Five (27.7%) out of the eighteen patients achieved best corrected visual acuity improvement of 6/36, whereas seven (38.8%) patients reached up to a BCVA of 6/60, with maximum improvement of two lines. The mean post-operative follow-up was 332.3± 46.7 days. CONCLUSION: Macular hole hydrodissection is a relatively new emerging technique with promising results for the closure of chronic persistent large macular hole.

Comparison of Retinal Nerve Fibre Layer versus Bruch Membrane Opening-Minimum Rim Width as an Optical Coherence Tomography-based Marker for Glaucoma in Myopia.

OBJECTIVE: To compare the reliability of Bruch Membrane Opening-Minimum Rim Width (BMO-MRW) Optical Coherence Tomography (OCT) with Retinal Nerve Fibre Layer (RNFL) in myopic patients. STUDY DESIGN: Cross-sectional study. PLACE AND DURATION OF STUDY: LRBT Free Base Eye Hospital, Karachi, from May 2019 to July 2020. METHODOLOGY: Moderate myopes with refractive errors between -3 to -6 diopters were examined by 2 glaucoma consultants separately, who performed fundoscopy to evaluate the optic nerve head, checked IOP and assessed CCT and visual fields to stratify the eyes into myopic normal and myopic glaucomatous eyes. All eyes were imaged with SD OCT of Spectralis version 1.10.2.0 of Heidelberg Engineering. Two scanning patterns, one for BMO-MRW and the other for RNFL thickness analysis, were performed. RESULTS: Fifty eyes of 50 patients were diagnosed with glaucoma in 50% (25 out of 50 patients). OCT RNFL detected glaucoma in 72% (36 out of 50 patients). While OCT BMO-MRW detected glaucoma in 56% (28 out of 50 patients). There was strong agreement between the consultant's judgements and BMO-based test (κ = 0.800, p <0.001), but the association was comparatively weaker with RNFL-based prediction (κ = 0.480, p <0.001). Specificity was better with OCT BMO-MRW (85.7%) than RNFL (66.7%). There were lower false positive rates with BMO-MRW (14.3%) than RNFL (33.3%). CONCLUSION: OCT BMO-MRW is a better indicator of glaucomatous damage in moderately myopic eyes as compared to OCT RNFL analysis. Key Words: Glaucoma, Myopia, Optical Coherence Tomography (OCT), Bruch Membrane Opening-Minimum Rim Width (BMO-MRW), Retinal Nerve Fibre Layer (RNFL).

Pre-operative predicting factor in visual outcome after macular hole surgery.

OBJECTIVE: To determine the effectiveness of macular hole index (MHI) as a predicting factor of visual outcome after full thickness macular hole surgery. METHODS: This quasi-experimental study was conducted at LRBT Free Base Eye Hospital, Karachi from January 2018 to March 2019. Total 45 eyes of 45 patients with full thickness macular hole (FTMH) underwent preoperative Best Corrected Visual Acuity (BCVA) assessment with logMar chart and Optical Coherence Tomography (OCT) scanning, with measurement of base diameter and macular hole height. Values were calculated for the macular hole index (MHI), which was taken as the predictive factor. All patients had undergone 25+G trans-conjunctival three ports pars plana vitrectomy, internal limiting membrane peeling, and endo-tamponade of C3F8(14%). The final visual outcome of all the patients was noted. RESULTS: Forty-five patients were included for the study, out of which 10 (22.2%) were male and 35 (77.7%) were female. Age ranged from 45-70 years (mean age 57.20±6.47 years). The mean pre-operative visual acuity was 2.46±1.15 logMar and was 3.88±2.00 logMar, post-operatively. Moreover, 27(60.0%) out of 45 patients achieved BCVA (gain of 2 lines of the logMar chart). The average macular hole index was 1.55±0.50 and out of 45, 25 patients had MHI ≥0.5. It was found that patients with macular hole index ≥0.50 showed clinically significant improvement in BCVA in comparison to those who have macular hole index <0.50. CONCLUSION: Macular hole index can be used to predict functional success in macular hole surgery.