Vestibular function assessment of Susac syndrome patients by the video head impulse test and cervical vestibular-evoked myogenic potentials

Article type: Research Article

Authors: Oron, Yahav^{1; a; *} | Handzel, Ophir^{a; 1} | Habot-Wilner, Zohar^b | Regev, Keren^c | Karni, Arnon^c | Zur, Dina^b | Baraquet, Dana^b | Goldstein, Michaella^b | Elkayam, Ori^d | Ungar, Omer J.^a

Affiliations: [a] Department of Otolaryngology, Head & Neck Surgery and Maxillofacial Surgery, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel, Affiliated to the Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel | [b] Division of Ophthalmology, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel, Affiliated to the Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel | [c] Department of Neurology, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel, Affiliated to the Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel | [d] Department of Rheumatology, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel, Affiliated to the Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel

Correspondence: [*] Corresponding author: Yahav Oron, MD, Department of Otol-aryngology-Head and Neck Surgery and Maxillofacial Surgery, Tel Aviv Sourasky Medical Center, 6 Weizmann Street, Tel Aviv, 6423906, Israel. Tel: +972 3 6973544; Fax: +972 3 6973543; E-mail: oron.yahav@gmail.com.

Note: [1] These authors contributed equally to this work.

Abstract: BACKGROUND:Susac syndrome (retino-cochleo-cerebral vasculopathy, SuS) is an autoimmune endotheliopathy characterized by the clinical triad of encephalopathy, branch retinal artery occlusions and sensorineural hearing loss. In contrast to data regarding auditory function, data measuring vestibular function is sparse and the cervical vestibular-evoked myogenic potentials (cVEMPs). OBJECTIVE:To determine whether the video head impulse test (vHIT) can serve as a confirmatory assessment of vestibulocochlear dysfunction in cases of suspected SuS. METHODS:Seven patients diagnosed with SuS underwent pure tone audiometry, a word recognition test, cVEMPs and the vHIT. RESULTS:Five patients were diagnosed with definite SuS, and two with probable SuS. Two patients were asymptomatic for hearing loss or tinnitus, and no sensorineural hearing loss was detected by audiograms. Four patients complained of tinnitus, and three patients reported experiencing vertigo. Three patients had abnormal cVEMPs results. All seven patients’ vHIT results were normal, except for patient #2, who was one of the three who complained of vertigo. The calculated gain of her left anterior semicircular canal was 0.5, without saccades. CONCLUSIONS:This is the first study to describe the results of the vHIT and cVEMPs among a group of patients with SuS. The results suggest that the vHIT should not be the only exam used to assess the function of the vestibular system of SuS patients.

Keywords: Susac syndrome, vestibular function, vHIT, cVEMP

DOI: 10.3233/VES-200007

Journal: Journal of Vestibular Research, vol. 30, no. 6, pp. 393-399, 2020