Visual evoked potentials after photostress in newly diagnosed insulin-dependent diabetes patients
•Background: The study was performed in order to ascertain whether electrophysiological abnormalities in visual function exist in newly diagnosed diabetic patients. •Methods: Visual evoked potentials (VEPs) were assessed under basal conditions and after photostress in normal control subjects and in newly diagnosed diabetic patients free of any fluorescein angiography signs of retinopathy. • Results: In basal conditions VEP P100 latency was significantly increased in the diabetic patients compared to controls (P<0.01), while N75-P100 amplitude was similar in both groups. After photostress N75-P100 amplitude (mean percentage decrement) was significantly higher in diabetic patients (P<0.01), while P100 latency (mean increment) and recovery time (time at which VEPs were superimposable on basal condition) were similar in the two groups. • Conclusions: The impaired basal VEPs suggest an early involvement of conduction in the optic nerve. In contrast, the preserved recovery time after photostress indicates that a short duration of disease does not induce physiopathological changes in macular function.