RÉSUMÉ
To determine the visual and anatomical outcomes and complications of vitrectomy for non-traumatic non-diabetic vitreous hemorrhage [NDVH] and to report the causes of the condition among patients at Labbafinejad Medical Center, Tehran-Iran, from 1993 to 2003. Records of patients who underwent vitrectomy for non-traumatic NDVH with 6 months follow up were reviewed for demographic characteristics, causes of NDVH and results of surgery. Fifty eyes [54.2% right eyes] of 49 patients [51% male] with mean age of 62.7 +/- 10.3 years were enrolled in the study. Mean visual acuity [VA] was 2.36 +/- 0.52 LogMAR and relative afferent pupillary defect [RAPD] was positive in 91.7% of the eyes, preoperatively. Causes of non-traumatic NDVH detected intraoperatively were: branch retinal vein occlusion [56%], central retinal vein occlusion [16%], choroidal neovascularization [12%], and posterior vitreous detachment with break, Eales disease, familial exudative vitreoretinopathy, and Terson syndrome [each in 4%]. Mean VA increased significantly at 6th month [1.38 +/- 0.72 IogMAR] compared to preoperative value. [P<0.0001] The most common causes of decreased VA were: macular pigmentary derangement [26%], optic atrophy [16%], severe lens opacity [12%], and epiretinal membrane [8%]. Despite the statistically significant increase in mean VA following vitrectomy, underlying macular pathology limits significant improvement of central VA in most cases of non-traumatic NDVH