Results of visual acuity and foveal thickness in diabetic macular edema after vitrectomy

Purpose: To report results of an investigation of visual acuity (VA) and foveal thickness in diabetic macular edema (DME) patients after vitrectomy. Methods: 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. Results: 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 1.2 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). Conclusions: 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.