A combination of retinal morphology and visual electrophysiology testing increases diagnostic yield in Parkinson's disease.

Abstract Background Impaired vision and remodeled foveal pit have been demonstrated in Parkinson's disease (PD) patients using different techniques. Methods Ten PD (20 eyes) and eight healthy controls (HC) subjects (16 eyes) were enrolled. Subjects were evaluated for N70 and P100 latencies using two-channel VEP with pattern reversal and on/off pattern; Contrast sensitivity (CS) using Pelli-Robson chart; macular thickness measured using Zeiss-HD optical coherence tomography (OCT). Results PD patients had a significantly delayed N70 (reversal pattern) and P100 (on/off pattern), lower CS score, and decreased retinal thickness at temporal 1.5–2.5 mm from the foveola. N70 latency was negatively correlated with CS (R = −0.419, P = 0.01) and average GCL-IPL thickness (R = −0.529, P = 0.001). CS was positively correlated with parafoveal thickness (R = 0.490, P = 0.002). A combination of parafoveal thickness and CS score yielded an AUC of 0.784 for PD discrimination which increased to 0.844 when combined with N70 and P100 measures. Conclusion A combination of pattern reversal VEP latency, CS score, and inner retinal foveal thickness measures has a high diagnostic yield for PD.