AUTHOR=Zhou Meng-Xi , Wang Qin , Lin Yin , Xu Qian , Wu Li , Chen Ya-Jing , Jiang Yu-Han , He Qing , Zhao Lei , Dong You-Rong , Liu Jian-Ren , Chen Wei 

TITLE=Oculomotor impairments in de novo Parkinson’s disease

JOURNAL=Frontiers in Aging Neuroscience

VOLUME=14

YEAR=2022

URL=https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2022.985679

DOI=10.3389/fnagi.2022.985679

ISSN=1663-4365

ABSTRACT=<sec><title>Objective</title><p>Reliable electrophysiological indicators are urgently needed in the precise evaluation of Parkinson’s disease (PD). It is still elusive whether oculomotor performance is impaired or has clinical value in early PD. This study aims to explore oculomotor performance in newly diagnosed, drug-naïve PD and its correlation with clinical phenotype.</p></sec><sec><title>Methods</title><p>Seventy-five patients with <italic>de novo</italic> PD, 75 patients with essential tremor (ET), and 46 gender-and age-matched healthy controls (HCs) were included in this cross-sectional study. All subjects underwent oculomotor test <italic>via</italic> videonystagmography. Visually guided saccade latency, saccadic accuracy and gain in smooth pursuit eye movement (SPEM) at three frequencies of the horizontal axis were compared among the three groups. Patients with PD also received detailed motor and non-motor evaluation by serial scales. The association between key oculomotor parameters and clinical phenotypes were explored in PD patients.</p></sec><sec><title>Results</title><p>Both <italic>de novo</italic> PD and ET patients showed prolonged saccadic latency and decreased saccadic accuracy relative to HCs. SPEM gain in PD was uniformly reduced at each frequency. SPEM gain at 0.4 Hz was also decreased in ET compared with HCs. However, there was no significant difference of oculomotor parameters between <italic>de novo</italic> PD and ET patients. Furthermore, prolonged saccadic latency was correlated with long disease duration, whereas decreased SPEM gain was associated with severe motor symptoms in <italic>de novo</italic> PD patients.</p></sec><sec><title>Conclusion</title><p>Ocular movements are impaired in <italic>de novo</italic>, drug naïve PD patients; these changes could be indicators for disease progression in PD.</p></sec>