Abstract
Abstract: :
Purpose: The Oscillatory potentials seem to reflect severe disturbances in the retinal circulation. Their amplitude are selectively reduced in ischemic retinopathies while the amplitude of the «a» and «b» waves of the ERG remains normal. We investigated the oscillatory potentials latencies in diabetic patients having no retinopathy or mild retinopathy. Method: We evaluated the oscillatory potentials and other ERG parameters in 30 eyes of 15 patients with adult onset diabetes mellitus without severe diabetic retinopathy. Patients were followed-up during three years. Results: The implicit time of the fifth oscillatory potential was initially, almost significantly (p=.06, t-test) delayed in eyes which developed progression of their retinopathy. Patients showing a complete posterior vitreous detachment had delayed implicit times in the first oscillatory potential (p<.05) but persistence of attached posterior vitreous was related to progression of retinopathy(p<.05). Conclusion: This longitudinal study show that among diabetic eyes with no or mild retinopathy, those with abnormal latencies in oscillatory potentials are more likely to show progression in their retinopathy. Oscillatory potential are thought to represent activity of the inner retina. Vitreous status may modify the electrical activity of the inner retina and induce changes in the oscillatory potentials.
Keywords: 388 diabetic retinopathy • 393 electrophysiology: clinical • 629 vitreous