Effect of Childhood Epilepsy and Antiepileptic Drugs on Visual Evoked Potential Response and Optical Coherence Tomography

Abstract Background The experience of evoked potentials in patients with epilepsy is sparse. Earlier studies in the literature, especially during the 1970s and 1980s, were conducted in previously treated epilepsy patients primarily to investigate drug effects or drug toxicity on afferent nerve conduction within the central nervous system. Aim of the Study to investigate effect of idiopathic childhood epilepsy per se on VEP and OCT and effect of two antiepileptic medications on them and correlate that with clinical symptoms if present. Patients and Methods this is a biphasic study, 1st one is case control and 2nd phase is a controlled clinical prospective trial, conducted in the neuro-pediatric outpatient clinic of Ain Shams University. This study enrolled 50 epileptic children drug naïve and 50 age and sex matched healthy controls, both groups were subjected to pattern reversed visual evoked potential and only 28 of the patients and 28 of the control group were subjected to ocular coherence tomography, starting from March 2021. The 50 patients were divided into 2 groups, the first one enrolled 23 patients that received levitracetam and the 2nd one enrolled 27 patients that received valproate. Both groups were followed up over 24 months and follow up VEP and OCT done to compare the two groups and correlate with the baseline parameters. Results 66% of the patients’ group was boys while 34% were girls, with mean age 10.5± 3.47. By measuring VEP in the two groups the mean P100 latency in the right eye and the left one of the control group was 110.4±3.76ms and 111.25±3.92ms respectively while in the patients group was 114.94±12.81ms and 115.37±11.88ms respectively that showed significant difference between the two groups with p- value 0.020 and 0.023 respectively. Conclusion there was prolonged latency in the epileptic children before starting AEDs more than the control group. This means that there was a disruption of the neural circuit by the epilepsy due to disruption of gabamenergic neurotransmitter system which plays an important role in mediating responses of cells in the visual cortex and retina and assists in shaping the receptive fields of the pyramidal cells in the superficial layers of the occipital cortex.