Association between oculomotor function testing parameters and Parkinson's disease

Parkinson's disease (PD) is characterized by motor and non-motor symptoms with oculomotor dysfunction being a notable feature. This study aimed to determine the oculomotor function in patients with PD using video-oculography (VOG) and to identify the association between physiologic parameters and PD.

The study enrolled 45 patients diagnosed with PD at onset and 45 age- and gender-matched healthy controls from July 2019 to July 2023. All participants underwent VOG testing. Eye movement parameters, including velocity, latency, gain, and accuracy, were quantified. The presence of square-wave jerks (SWJs) and abnormal tracking patterns was also assessed. Binary logistic regression and receiver operating characteristic (ROC) curve analyses were used to evaluate the associations between VOG testing parameters and PD.

Patients with PD demonstrated a significantly higher SWJ rate, reduced pursuit gain, prolonged saccade latency, and slower saccade velocity compared to controls (P < 0.05). SWJs, decreased pursuit gain, and prolonged saccade latency were closely related to PD based on logistic regression analysis. The combined detection index incorporating these 3 parameters yielded an area under the ROC curve of 0.836 (95 % CI: 0.752-0.920; P < 0.001) with 77.8 % sensitivity and 82.2 % specificity.

Assessment of oculomotor function using VOG demonstrated notable abnormalities in patients with PD, especially with respect to fixation stability, smooth pursuit, and saccadic control. A combined index incorporating SWJs, pursuit gain, and saccade latency significantly improved PD screening precision.