Abstract
Purpose:
Removal of the internal limiting membrane (ILM) during pars plana vitrectomy (PPV) has been shown to improve macular hole closure, reduce rates of post operative epiretinal membrane (ERM) formation in rhegmatogenous retinal detachments, and reduce macular thickness in patients with refractory diabetic macular edema. We conducted a retrospective study evaluating clinical outcomes in patients who underwent ILM peeling during pars plana vitrectomy for the treatment of proliferative diabetic retinopathy.
Methods:
We analyzed the outcomes of 71 patients (71 eyes) who underwent PPV and epiretinal membrane peeling, with or without ILM removal, for proliferative diabetic retinopathy complicated by tractional retinal detachment and/or vitreous hemorrhage. All patients had 12 months of post-operative follow up. The primary outcome measure at 12 months was ERM recurrence. The secondary outcomes were the presence of clinically significant macular edema (CSME) and visual acuity. Preoperative and intraoperative baseline characteristics of both groups were also analyzed. ANOVA, 2 tail independent sample t-test and Pearson Chi Square tests were performed where appropriate.
Results:
Of the 71 cases that met inclusion criteria, 22 underwent ILM peeling in addition to ERM removal, and 49 underwent ERM removal alone. At 12 months, 3 patients in the ILM peel group had developed post-operative ERMs, as opposed to 16 in the non-ILM peel group (p=0.094). 3 patients in the ILM peel group developed post operative CSME within the first 12 months, as opposed to 5 in the non-ILM peel group (p=0.672). There was no statistically significant difference in the final post-operative logMAR visual acuity (p=0.901). No significant associations existed between post-operative ERM formation and a number of pre- and intra-operative variables examined; however, a significant association existed between the presence of a rhegmatogenous break or detachment and the occurence of post-operative CSME.
Conclusions:
Our results suggest that ILM peeling in proliferative diabetic retinopathy may have a limited impact on post-surgical outcomes. However, given the evidence showing better outcomes for patients undergoing ILM peel for other disorders and the relative paucity in the literature on this topic, further investigation is warranted.