Objectives: This study evaluates Visual Evoked Potential (VEP) and Optical Coherence Tomography (OCT) in Idiopathic Parkinsonís Disease (PD) Patients; analyzes the relation between the diseaseís severity and such values, and investigates the presence of interocular asymmetry in patients with one-sided dominance. Methods: 40 eyes of 20 PD patients at various stages were evaluated. The diseaseís severity was measured via UPDRS (Unified Parkinsonís Disease Rating Scale) and Hoehn&Yahr (H&Y) scales. Results: There were 21 (52%) eyes with a pathological P100 latency. P100 latency prolonged as the H&Y staging went up; however, it was not statistically significant. Retinal nerve fiber layer (RNFL) thickness was normal in 70% and retinal thinning was found in 25% of the eyes. The most thinning was observed in the lower and upper quadrant, respectively. Central macular thickness decreased in 62.5% and macular volume decreased in 70% of the eyes. The difference in average RNFL thickness was higher in patients with motor involvement on the left (p=0.044). Conclusion: It was observed that P100 latency prolonged in parallel with the progression of the disease stage, and average RNFL thickness increased in advanced stages while the central macular thickness and volume decreased. P100 latency can be measured in addition to UPDRS for evaluating the PDís severity. Keywords: Optical coherence tomography, parkinsonís disease, retinal nerve fiber thickness, visual evoked potential
Corresponding Author: Ustun Ozek S.