Prognostication of Relative Visual Improvement after Epiretinal Membrane Surgery

<title>Abstract</title> <p> <bold>PURPOSE:</bold> To analyse pre-operative factors for best prognostic markers of relative visual improvement after vitrectomy for epiretinal membrane (ERM). <bold>METHODS:</bold> Retrospective cohort study. Pre-operative data included baseline demographics, visual acuity, lens status, duration of symptoms. optical coherence tomography parameters and visual acuity (VA) data were collected pre-operatively, at 6 months and 12 months post-operatively. Patient were divided into 2 groups, with group 1 including patients with less than 2 lines logMAR BCVA improvement and group 2 including those with 2 or more lines logMAR BCVA improvement. Statistical analysis was performed using SPSS. <bold>RESULTS:</bold> Of 95 eyes operated, 59 eyes were included with 26 (44%) in group 1 and 33 (56%) in group 2. The mean preoperative BCVA was 0.59 ± 0.28 logMAR and improved to 0.41 ± 0.25 logMAR at 6 months and 0.35 ±0.26 logMAR at 12 months (P &lt; .001). For the whole cohort, males were more likely to improve 2 or more lines (25 of 34 (75.8%)) versus females (8 of 25 (24.2%)) (p&lt;0.001) as well as patients with shorter duration of symptoms (p=0.026) with a cut off value of 12 months or less (88.89 % sensitivity 62.50 % specificity). Patients with secondary ERM were more likely to gain 2 or more lines (12 of 15 (80%)) versus patients with primary ERM (21 of 44 (47%)) (p=0.03). For the whole cohort, patients with higher preoperative CRT with cut off value of 478 mm (60.61 % sensitivity 69.23 % specificity) were more likely to improve 2 or more line (p=0.03) as well as those with MME sign on preoperative OCT (20 of 29 (69%)) (p=0.047). <bold>CONCLUSION:</bold> Clinical and OCT parameters more likely to be associated with significant visual acuity improvement of 2 or more lines after ERM surgery were male gender, shorter duration of symptoms (&lt;12 months), secondary ERM etiology, higher preoperative CRT (&gt;478 mm), and presence of MME preoperatively. These may be regarded as basis for patient counselling and prioritization. <bold>None of the authors has any financial or competing interest to disclose</bold> </p>