Assessment of visual evoked potential in patients with primary open-angle glaucoma attending a tertiary care hospital: A case-control study

Background: Primary open-angle glaucoma (POAG), the leading cause of blindness in India, has an insidious onset and lack of early symptoms often leading to late diagnosis, which highlights the need for effective screening methods. The specific cause is associated with irreversible damage to the optic nerve due to increased intraocular pressure. Visual evoked potentials (VEPs) are electrophysiological tests used to measure the electrical responses generated in the visual cortex in response to visual stimuli. Objective: To evaluate the utility of VEP testing as a screening tool to detect early cases of glaucoma. Materials and Methods: This case-control study aimed to evaluate pattern-reversal visual evoked potentials (PRVEPs) in early cases of POAG compared with healthy controls. Our study sample included 30 patients diagnosed with POAG who, together with age-matched controls, were tested for VEPs. Results. Significant delays in N70, P100 and N145 latencies were observed in the POAG group vs. the controls. The results showed significant differences in VEP parameters between the control and case groups. The latencies of N70, P100 and N145 were prolonged in patients with POAG, indicating a delay in nerve conduction along the visual pathway. Although the decrease in P100 amplitude was not statistically significant, the changes in latency were highly significant. Conclusion: VEPs may serve as a valuable screening tool for early neuro-ophthalmic deficits in the detection and monitoring of glaucoma in tertiary care hospitals, facilitating timely intervention and preventing irreversible vision loss in patients with glaucoma.