Abstract
Purpose:
to evaluate the effect of 25 G pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling in diabetic patients with clinicallly significant diffuse macular edema no more responsive to standard therapies.
Methods:
retrospective analysis of visual acuity (VA), SD-OCT (HRA+OCT Spectralis, Heidelberg Engineering GmbH, Heidelberg, Germany) and fluorescein angiography images of 20 eyes of 20 vitrectomized patients with diagnosis of diabetic macular edema. Each patient was already submitted to intravitreal Bevacizumab and/or posterior pole laser treatment without success. Patients presenting at baseline with vitreomacular traction and/or microaneurisms suitable to laser treatment were excluded. 25 G pars plana vitrectomy with ILM peeling and cataract surgery when necessary were performed after 3 months wash-out. Operations were done by 3 different surgeons (FB, MC, SdeA). Selective Argon laser on peripheral areas of ischemia was performed during surgery if present. Mean preoperative VA and central retinal thickness (CRT) were compared to mean VA and CRT at 1, 3, 6, 9, and 12 months postop. The model was analyzed with Walter matrices (i.e., each dummy variable tests if VA and CRT changed significantly from the previous time point). Preoperative VA and CRT at T0 were used for the intercept. Predictive factors for anatomical and functional outcomes such as pre-op VA, CRT, presence of a posterior vitreous detachment, epiretinal membrane or IS-OS defect, were also investigated.
Results:
No major complications occurred during and after surgeries.Visual acuity range was beetween 0,01 and 0,5 (Mean 0,18 +- 0,12) at baseline. Mean VA was 0,27 +-0,17 at 1 month, 0,32 +-0,2 at 3 months, 0,36 +-0,22 at 6, 0,36+-0.22 at 9 and 0,38 +-0.22 at 12 months follow-up. CRT was beetween 391 and 976 microns at baseline (Mean 645,2 +- 159,6). Mean CRT was 403 +- 114.4 microns at 1 month, 382 +-127 microns at 3, 352 +-123 microns at 6, 343.6+-129.9 microns at 9 and 337.1 +-126.5 microns at 12 months follow-up. The greatest reduction for both VA and CRT was beetween time 0 and 1.
Conclusions:
PPV with ILM peeling is effective in diabetic patients with clinically significant macular edema no more responder to standard care to reduce retinal thickness and improve visual acuity. The only factor able to predict the reduction of CME was the presence of a PVD before surgery.
Keywords: 762 vitreoretinal surgery •
505 edema •
499 diabetic retinopathy