Abstract
Purpose: :
To evaluate the surgical outcomes of epiretinal membrane (ERM) removal with and without internal limiting membrane (ILM) peel in patients tractional retinal detachment (TRD) secondary to proliferative diabetic retinopathy (PDR).
Methods: :
A retrospective chart review of patients with TRD secondary to PDR who underwent pars plana vitrectomy (PPV) with ERM removal with or without ILM peel between August 2005 and June 2008 by single surgeon (SMH). Main outcome measures were pre- & postoperative visual acutiy (VA) and central macular thickness (CMT) as measured by optical coherence tomography (OCT). None of the patients had clinically significant diabetic macular edema preoperatively. Mean follow-up was 6 months (30 days-1year). Patients with prior vitreoretinal surgery were excluded.
Results: :
Thirty eyes of 28 patients meeting the criteria were evaluated. Nineteen patients (63.3%) underwent ERM peel only and eleven patients (36.6%) underwent ERM & ILM peel. Mean preoperative logMAR VA was 0.87 (range, 0.20-2.00), and CMT was 378µm. Mean logMAR VA at final follow-up was 0.72 (range, 0.20-2.00) and mean CMT was 257µm. The average improvement in logMAR VA at final follow-up was 1.5 lines (p=0.03), with mean CMT decrease of 121µm (p=0.006). In the ERM peel only group, mean logMAR VA at final follow-up was 0.89 (range, 0.20-2.00) and in the ERM & ILM peel group, it was 0.45 (range, 0.30-0.70). The ERM peel only group gained 1 line on average (p=0.12) and the ERM & ILM peel group gained 2 lines on average (p=0.002). Patients in the ERM peel only group on average had worse pre-operative logMAR VA than patients in ERM & ILM peel group (1.03 vs. 0.59), and showed less visual improvement (1 vs. 2 lines). The average CMT decrease in the ERM peel only group was 165µm (p=0.02), and in the ERM & ILM peel group was 56µm (p=0.08). Age was not found to correlate significantly with visual or anatomic improvement.
Conclusions: :
Pars plana vitrectomy with ERM peeling in patients with TRD secondary to PDR was associated with overall improvement in VA and restoration of retinal anatomy. Even though the change in CMT was greater in the ERM peel only group, the final postoperative CMT was comparable in both groups. The group with both ERM and ILM peel gained more lines of vision than the ERM peel only group. In addition, the former group also had the better final VA at the latest follow-up. These results suggest that PPV with ERM peel is beneficial in patients with TRD secondary to PDR. In addition, the additional step of peeling ILM appears to confer further visual improvement in patients with TRD, though larger controlled studies are needed to confirm this hypothesis.
Keywords: vitreoretinal surgery • retina