Pars plana vitrectomy in diabetic macular edema

Purpose: To ascertain the association between the improvement of diabetic macular edema and increased visual acuity after pars plana vitrectomy. Methods: From January 1994 to December 1996 we prospectively studied 18 patients (18 eyes, 7 women and 11 men, mean age 52 years, range 37-68) with type II diabetes and clinically significant macular edema. One group was composed of 9 patients presenting diffuse macular edema (DME); a second group with 9 patients presented cystoid macular edema (CME). All patients underwent pars plana vitrectomy. Results: Preoperative Snellen visual acuity was 20/143 in DME and 20/441 in CME. In both groups vision increased to 20/136 and 20/205, respectively, postoperatively. For the DME this difference was statistically significant (p < 0.05) at 1 month after the surgery, but vision decreased again after 10 months reaching preoperative values. Conclusions: Our results suggest that pars plana vitrectomy for diabetic macular edema may increase visual acuity in diffuse macular edema, although this increase is only short lived.