vitrectomy for diffuse refractory diabetic macular edema associated with a taut premacular posterior hyaloid

purpose: to evaluate the anatomic and visual results and complications of vitrectomy in eyes with diffuse refractory diabetic macular edema associated with a taut posterior hyaloid. methods: this prospective interventional case series was conducted on 25 eyes of 22 patients with diffuse clinically significant diabetic macular edema, macular thickness greater than 250 microns on optic coherence tomography (oct) and thickened posterior hyaloid. best-corrected visual acuity (bcva) and macular thickness measured by oct were evaluated preoperatively and 3 and 6 months postoperatively. macular perfusion was evaluated by fluorescein angiography, preoperatively. results: mean bcva was 1.14±0.51 logmar, preoperatively and 0.89±0. 53 logmar 6 months postoperatively (p= 0.005). mean preoperative macular thickness was 506±121.9 µm which decreased to 318±90.5 µm, postoperatively (p=0.001). conclusion: vitrectomy with removal of the posterior hyaloid membrane appears to be beneficial in some cases of diffuse persistent diabetic macular edema with a taut premacular posterior hyaloid unresponsive to laser therapy. careful selection of eyes with favorable preoperative clinical characteristics may improve surgical outcomes.