Nonmydriatic digital retinal images for determining diabetic retinopathy.

OBJECTIVE: To evaluate the efficacy of nonmydriatic digital retinal images for determining diabetic retinopathy. MATERIAL AND METHOD: Single field 45-degree digital retinal images of 225 eyes from 142 diabetic patients were obtained with a nonmydriatic camera. The images were diagnosed and graded by a general ophthalmologist. These results were compared with clinical diagnosis obtained by retinal specialists, after examination by using biomicroscope with plus lens and indirect ophthalmoscope of the patients. International clinical diabetic retinopathy disease severity scale was used for grading diabetic retinopathy in all cases. RESULTS: Presence of diabetic retinopathy was detected in 70 eyes (31.1%). The sensitivity and specificity for determining diabetic retinopathy was 68.57% (95%CI 57.00-78.20) and 92.25% (95%CI 87.00-95.50), respectively. The positive predictive value and negative predictive value was 80.00% (95%CI 68.20-88.20) and 86.67% (95%CI 80.60-91.00). Overall accuracy was 84.89%. CONCLUSION: Single field 45-degree nonmydriatic digital retinal images were limited by fair sensitivity for determining diabetic retinopathy although overall accuracy from the present study was relatively high. Upcountry, this tool might facilitate increased access of diabetic patients for eye evaluation but cannot replace standard eye examination.

Von willebrand factor levels in patients with diabetic retinopathy.

Plasma levels of von Willebrand factor (vWF), an indicator for endothelial injury, were measured in type II diabetic patients with or without retinopathy and 20 normal control subjects. Patients were grouped according to their degree of retinopathy, 12 patients with no evidence of retinopathy, 19 patients with background retinopathy and 23 patients with proliferative retinopathy. All groups of diabetic patients had significantly higher vWF levels when compared to normal controls. But the levels of vWF did not correlate with the severity of retinopathy. The data suggested that diabetic patients had some degree of endothelial injury that might not relate to the development of retinopathy.

Fibrinolytic activity in patients with diabetic retinopathy.

Tissue plasminogen activator (t-PA), plasminogen activator inhibitor (PAI-1) and plasminogen concentrations were measured in 62 patients with non-insulin dependent (type II) diabetes mellitus. Patients were grouped according to their degree of retinopathy; 13 patients with no evidence of retionpathy (BDR) and 26 patients with proliferative retinopathy (PDR). Twenty healthy individuals served as normal controls. PAI-1 levels of all diabetic groups were found to be lower than control group. But the difference was statistically significant only between PDR and controls. Plasminogen levels in diabetic groups were higher than in the control group, especially in the PDR group. There was no difference in t-PA levels between diabetics and the control group. It is concludedthat PAI is closely related with the development of retinopathy in diabetic patients.