Preoperative prognostic factors in vitrectomy for severe proliferative diabetic retinopathy

PurposeTo investigate the preoperative prognostic factors contributing to extremely poor visual outcome in cases of proliferative diabetic retinopathy after a successful vitrectomy and an uneventful postoperative course.MethodsWe enrolled 28 consecutive eyes of 28 patients with poor preoperative visual acuity (VA), who underwent primary diabetic vitrectomy. The postoperative course was uneventful, and retinal attachment was achieved for at least 6 months in all cases. The cases were separated into the study group (postoperative VA < preoperative VA) and control group (postoperative VA ≥ preoperative VA). Preoperative factors including systemic diseases, demographic data, proliferative diabetic retinopathy severity, and neovascularization status were compared between the two groups. Significant risk factors for poor visual results were determined by logistic regression analysis.ResultsThe creatinine level was significantly higher in the study group (4.07 ± 4.15 mg/dL) than in the control group (1.23 ± 0.46 mg/dL; p = 0.003). Chronic macular detachment was noted in 7/10 eyes (70%) in the study group and in 1/18 eyes (5.6%) in the control group (p = 0.001). Broad fibrovascular proliferation extending to the periphery for more than two quadrants was found in 4/10 eyes (40%) in the study group and in none of the eyes in the control group (p = 0.016). Chronic macular detachment and broad fibrovascular proliferation were significantly associated with poor visual outcome in multiple logistic regression analysis.ConclusionPreoperative chronic macular detachment, broad fibrovascular proliferation, and poor renal function may indicate worse visual results after successful diabetic vitrectomy for cases with severe diabetic retinopathy.