Visual fixation suppression of caloric nystagmus in progressive supranuclear palsy – A comparison with Parkinson’s disease

Article type: Research Article

Authors: Naito, Rie^{a; *} | Watanabe, Yuki^a | Naito, Akira^a | Sugasawa, Keiko^a | Nakata, Yasuhiro^b | Kamiyama, Tsutomu^b | Okiyama, Ryoichi^c | Yokochi, Fusako^c | Isozaki, Eiji^c | Yamasoba, Tatsuya^d | Takahashi, Kazushi^c

Affiliations: [a] Department of Neuro-Otology, Tokyo Metropolitan Neurological Hospital, Fuchu, Tokyo, Japan | [b] Department of Neuro-Radiology, Tokyo Metropolitan Neurological Hospital, Fuchu, Tokyo, Japan | [c] Department of Neurology, Tokyo Metropolitan Neurological Hospital, Fuchu, Tokyo, Japan | [d] Department of Otolaryngology and Head and Neck Surgery, Graduate School of Medicines, University of Tokyo, Bunkyo-ku, Tokyo, Japan

Correspondence: [*] Corresponding author: Rie Naito, Ph.D., M.D., Department of Neuro-Otology, Tokyo Metropolitan Neurological Hospital, 2-6-1 Musashi-dai, Fuchu, Tokyo 183-0042, Japan. Tel.: +81 (42) 323 5110; Fax: +81 (42) 322 6219; E-mail: [email protected].

Abstract: BACKGROUND:Impairment of visual fixation suppression (VS) in progressive supranuclear palsy (PSP) is not well documented. OBJECTIVE:To evaluate the usefulness of impaired VS of caloric nystagmus as an index for differential diagnosis between PSP and Parkinson’s disease (PD), which is often difficult, especially in the early stage. METHODS:Subjects comprised 26 PSP patients and 26 PD patients clinically diagnosed at Tokyo Metropolitan Neurological Hospital. We retrospectively investigated VS of caloric nystagmus, horizontal pursuit, saccades, and horizontal optokinetic nystagmus recorded on direct-current-electronystagmography, and neuroradiological findings. RESULTS:The median of the average VS% was 0% and 50.0% in PSP and PD patients, respectively. In PSP, VS was impaired even in the early stage of disease. We found a significant correlation between VS and velocity of saccades or maximum slow phase velocity of optokinetic nystagmus only in PSP patients. PSP patients with atrophy of the subthalamic nucleus or with decreased blood flow in the frontal lobe showed significantly more severe impairment of VS. CONCLUSIONS:VS may be a useful biomarker to differentiate patients with PSP from those with PD. Cerebellar networks that connect with the cerebral cortex and basal ganglia may contribute to impaired VS of caloric nystagmus in PSP.

Keywords: Progressive supranuclear palsy, visual fixation suppression, caloric nystagmus, subthalamic nucleus, cortico-basal-cerebellar network

DOI: 10.3233/VES-210147

Journal: Journal of Vestibular Research, vol. 33, no. 6, pp. 385-401, 2023