Macular hole formation in diabetic retinopathy: the role of coexisting macular edema

The aim of this study was to characterise different etiologies for the deve lopment of macular holes in diabetic retinopathy. We examined 8 eyes of 8 p atients with known diabetic retinopathy who had developed a macular hole. T hese were classified as follows: related to macular edema (4 eyes), non-rel ated to macular edema (2 eyes), intraoperative (1 eye) or postoperative (1 eye) after pars plana vitrectomy for proliferative diabetic retinopathy. In three patients the macular holes were treated with pars plana vitrectomy a nd fluid air exchange. In diabetic eyes with macular edema, macular holes may develop because of i ntraretinal exudation combined with increased vitreomacular attachments and tractions. The mechanism of macular hole formation in diabetic eyes withou t macular edema probably results from the same increased tangential vitreou s traction which is seen in idiopathic age-related macular holes. Iatrogeni cally induced macular holes during pars plana vitrectomy for proliferative diabetic retinopathy may be also due to intraoperative vitreoretinal tuggin g. Finally, macular holes developing after vitrectomy may have an etiology not related to vitreous tractions or attachments.