Results of Visual Acuity and Foveal Thickness in Diabetic Macular Edema after Vitrectomy

Abstract

To report results of an investigation of visual acuity (VA) and foveal thickness in diabetic macular edema (DME) patients after vitrectomy. A retrospective study was performed of the records of 47 patients (61 eyes) who received pars plana vitrectomy (PPV) for DME. All eyes were followed up for over 6 months (mean, 24.8 months; range, 6-60 months). VA and foveal thickness evaluated by optical coherence tomography were reviewed preoperatively and postoperatively. Twenty-four-month follow-up data were available for 46 of the 61 eyes (75%). VA at the final examination had improved by 0.2 log units or more in 34 of the 61 eyes (56%), remained unchanged in 21 eyes (34%), and worsened in six eyes (10%). Mean foveal thickness decreased by more than 20% of the preoperative value in 50 of the 61 eyes (82%), remained unchanged in ten eyes (16%), and increased by more than 20% in one eye (2%) at the final examination. Postoperative best-corrected visual acuity (BCVA) at both 12 and 24 months was significantly better than preoperative BCVA (P < 0.0001). Foveal thickness at 3 months or later significantly decreased from the preoperative value (P < 0.0001), but remained unchanged in comparison with postoperative 12 months and 24 months values (P = 0.19). Preoperative VA and presence of cystoid macular edema (CME) were independently associated with final visual acuity (P = 0.001). PPV for DME effectively improved VA and reduced foveal thickness for a longer postoperative period. Better preoperative VA was associated with better final postoperative VA. The eyes without CME tended to have better final postoperative VA.