Clinical analyses of late vitreous hemorrhage after vitreoretinal surgery in proliferative diabeticretinopathy

Objective To observe the expression of VEGF in the postoperative late vitreous hemorrhage (LVH) after vitrectomy for proliferative diabetic retinopathy (PDR) patients, and how VEGF level changes in patients with LVH (74 weeks) . Methods Seventy-three patients (82 eyes) with PDR who underwent vitrectomy were analyzed retrospectively. Vitreous samples were collected from eyes undergoing primary vitrectomy and from eyes with LVH undergoing second vitrectomy. Vitreous VEGF levels were measured using ELISA. According to the occurrence or absence of LVH after PPV, the patients were divided into the non LVH, LVH groups, and the patients with intraocular foreign body injuries who needed emergent intraocular surgeries were served as the normal control. Results LVH occurred in 19 (23%) of 82 eyes, and 5 eyes (6%) required second vitrectomy. VEGF level was significantly higher in PDR patients than that in normal control (P <0.01), was significantly higher in LVH than that in non LVH (P <0.05), (P <0.01). Conclusions In patients with PDR, high intraocular VEGF level after primary vitrectomy was identified as a risk factor of postoperative LVH. Persistent overproduction of intraocular VEGF may be associated with postoperative LVH. Key words: VEGF; Pars plana vitrectomy; PDR; Late vitreous hemorrhage