Abstract
Purpose: :
To examine the preoperative anatomical features of the macula using Stratus optical coherence tomography (OCT) in patients with epiretinal membranes (ERM) who underwent pars plana vitrectomy for ERM removal, and to correlate these features with anatomic and visual outcomes.
Methods: :
The study was a retrospective, single center, noncomparative, interventional case series. Thirty nine eyes of 39 patients with ERM who met inclusion/exclusion criteria underwent vitrectomy and epiretinal membrane removal between January 2005 and November 2007. Patients were evaluated clinically and by OCT preoperatively and at 1 week, 1 month, 3 months, and their most recent clinic visit. Inclusion criteria included availability of pre- and post-operative OCT imaging, and clinical follow-up of 3 or more months. Exclusion criteria included OCT diagnoses of vitreomacular traction, lamellar hole, or macular hole. OCT appearances were classified as focal, broad-patchy, or global adherence of ERM, and presence of cystoid macular edema (CME) was noted.
Results: :
ERMs were idiopathic in 56% (n=22) eyes. Etiologies of secondary ERM included previous retinal surgery, argon laser for retinal tears, uveitis, choroidal neovascularization, and proliferative diabetic retinopathy. Mean follow-up was 16.6 months. Mean preoperative visual acuity was 20/130. Mean preoperative CRT was 448 ± 108 µm. At 6 months follow-up, visual acuity was 20/90 and mean CRT was 405 ± 137 µm. Of patients with at least 18 months follow-up, mean postoperative visual acuity at last examination was 20/75 and mean CRT was 340 ± 125.4 µm. On preoperative OCT, ERM adherence to the retina was classified as focally in 28% (n=11), broad-patchy in 23% (n=9), and globally in 49% (n= 19). There was no significant difference in postoperative visual acuity between the 3 types of preoperative ERM (p=0.96). Forty-three percent (n=16) of eyes had preoperative CME. Eyes with preoperative CME had significantly poorer VA outcomes as compared to eyes without CME at baseline.
Conclusions: :
Different morphological types of ERM categorized using preoperative OCT had no prognostic influence on postoperative visual acuity. The presence of CME on preoperative OCT did have a significantly negative impact on long-term postoperative visual acuity. This was especially evident in primary epiretinal membranes.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • vitreoretinal surgery • retinal glia