Pattern Visual Evoked Potentials in Patients with Type II Diabetes Mellitus

Purpose: to evaluate cortical and retinal activity by pattern visual evoked potentials (pvep) in patients with type ii diabetes mellitus.methods: pvep was recorded in 40 diabetic patients including 20 subjects with non-proliferative diabetic retinopathy (npdr) and 20 others without any retinopathy on fundus photography, and compared to 40 age- and sex-matched normal non-diabetic controls.results: p100 wave latency was significantly longer in diabetic patients as compared to normal controls (p<0.001); both diabetic subjects without retinopathy and those with npdr had significantly longer p100 latency than controls (p<0.001 for both comparisons). there was significant reduction in n75 (p=0.037) and p100 (p=0.001) amplitudes in diabetic subjects. no correlation was observed between vep amplitude or wave latency, and the level of glycemia or duration of diabetes mellitus. conclusion: increased pvep latency may be a sign of retinal ganglion cell damage which takes place before the appearance of the first ophthalmoscopically detectable signs of diabetic retinopathy. pvep may be considered as a method for detecting prediabetic retinopathy and has the potential to reduce diabetic complications