Epiretinal Membrane Surgery after Retinal Detachment Repair: Visual Acuity Outcomes and OCT Analysis

Purpose: To assess visual acuity (VA) outcomes of epiretinal membrane (ERM) surgery following primary rhegmatogenous retinal detachment (RD) repair and to identify OCT features predictive of visual outcomes.

Design: Retrospective, consecutive case series.

Subjects: Eyes undergoing pars plana vitrectomy (PPV) with membrane peel (MP) surgery for ERM following primary RD repair (PPV with or without scleral buckle (SB) and gas tamponade).

Methods: Retrospective chart review from 2015 to 2018. A previously described ERM grading scale was utilized for OCT structural analysis.

Main outcome measures: Visual acuity (VA) and change in VA from pre- MP to 6 months and final follow-up. Secondary outcomes included RD and OCT features predictive of VA, as well as RD factors associated with need for subsequent MP surgery.

Results: 53 eyes of 53 patients underwent MP following RD repair. VA improved significantly from logMAR 1.00 ± 0.51 (Snellen 20/200) pre-MP to 0.45 ± 0.41 (20/56) at 6 months and 0.42 ± 0.41 (20/53) at final follow-up, (p<0.001) for each respectively. Macula on eyes had better 6 month [0.29 ± 0.18 (20/39) vs. 0.51 ± 0.46 (20/65), p=0.02] and final VA [0.29 ± 0.14 (20/39) vs. 0.46 ± 0.47 (20/58), p=0.04] after MP surgery. VA improved significantly from pre-MP to 6 months and final follow-up regardless of macula status. MP occurring ≤180 days from RD repair and IS/OS loss were associated with worse pre-MP VA [1.13 ± 0.09 (20/270) vs. 0.82 ± 0.07(20/132), p=0.01 and 1.21 ± 0.07 (20/324) vs. 0.74 ± 0.09 (20/110) p=0.0003, respectively]. IS/OS loss [adjusted means 0.54 ± 0.07 (20/69) vs. 0.25 ± 0.08 (20/36) at final visit, p=0.006] and RD repair with PPV/SB [0.53 ± 0.08 (20/68) vs. 0.31 ±0.07 (20/41) at final visit, p=0.03] were significantly associated with worse VA at both 6 months and final follow-up.

Conclusions: Eyes undergoing MP after RD repair have significant visual acuity gains independent of macula-status at time of RD repair. Pre-operative IS/OS disruption was the OCT feature best predictive of visual acuity.