Visual Evoked Potential In Normal Individuals And In Diabetic Patients Without Retinopathy - A Comparative Study

Abstract

Background:  Diabetic Retinopathy can lead to irreparable loss of vision if not treated early. Visual evoked potential (VEP) is a non-invasive neurophysiological examination that can be used to detect very early retinopathic changes by detecting the retinal ganglion cell damage measured by the latency. In our study we are comparing the VEP in normal individuals and diabetic patients without retinopathy .

Aim:     To detect changes in Visual Evoked Potential in diabetic patients without retinopathy and to compare the amplitude and latency in normal individuals.

Methodology:

A cross sectional study.

Inclusion criteria:

Both sexes.

Patients with diabetes and no retinopathy

Patients without Retinopathy.

Exclusion criteria:

Other Metabolic disorders.

Corneal or lenticular opacity.

Disorders of Peripheral nervous system.

Any blood disorders.       

Study group: The patients were divided into 2 groups. 50 patients in each group

Examination and Testing:  After Detailed history and general examination, all the patients were subjected to ophthalmic examination to rule out retinopathy and subjected to VEP

Results:  The mean P100 latencies in diabetic patients were significantly prolonged (p < 0.05) compared to controls

The mean P100-N145 amplitude in diabetic patients were significantly reduced (P < 0.05) compared to controls

The mean P100 – N145 amplitude was significantly reduced with the increasing duration of diabetes. (p.value <0.05)

Conclusion: This study shows that the VEP changes may be related to the poor control and long duration of the disease and hence can be used as a marker for assessing early diabetic retinopathy changes.