Cerebellar ataxia with neuropathy and vestibular areflexia syndrome (CANVAS) is a recently described slowly progressive ataxia with severe imbalance due to the compromise of three of the four sensory inputs for balance, leaving only vision unaffected. Bilateral vestibulopathy is present but saccular and utricular function, measured by vestibular evoked myogenic potentials (VEMPs), has not been widely studied in these patients. Dysautonomia has been reported but is not among the diagnostic criteria. We performed a database analysis to identify patients evaluated between 2003 and 2019 with probable diagnosis of CANVAS by using key words “bilateral vestibulopathy and/or cerebellar ataxia and/or sensory polyneuropathy.” Five out of 842 met all conditions. Patients underwent neurological/neurootological exam, brain MRI, visually enhanced vestibulo-ocular reflex (VVOR) exam by high-speed video-oculography using video-Head Impulse Test (vHIT), VEMPs, neurophysiological studies, and genetic tests to exclude other causes of ataxia. Dysautonomia was addressed by the standardized survey of autonomic symptoms. All patients had clinically definite CANVAS as brain MRI showed vermal cerebellar atrophy, neurophysiological studies showed a sensory neuronopathy pattern (absent sensory action potentials), VVOR was abnormal bilaterally, and genetic tests ruled out other causes of ataxia including SCA 3 and Friedreich ataxia. Patients had at least 3 dysautonomic symptoms, including xerostomia/xerophthalmia (5/5). VEMP results varied among patients, ranging from normal to completely abnormal. We found inconsistent results with VEMPs. The utilization of VEMPs in more CANVAS cases will determine its utility in this syndrome. Dysautonomia may be included in the diagnostic criteria.
This is a preview of subscription content, log in to check access.
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
Migliaccio AA, Halmagyi GM, McGarvie LA, Cremer PD. Cerebellar ataxia with bilateral vestibulopathy: description of a syndrome and its characteristic clinical sign. Brain. 2004;127(Pt 2):280–93.CrossRefGoogle Scholar
Szmulewicz DJ, Waterston JA, Halmagyi GM, Mossman S, Chancellor AM, McLean CA, et al. Sensory neuropathy as part of the cerebellar ataxia neuropathy vestibular areflexia syndrome. Neurology. 2011;76(22):1903–10.CrossRefGoogle Scholar
Szmulewicz DJ, Roberts L, McLean CA, MacDougall HG, Halmagyi GM, Storey E. Proposed diagnostic criteria for cerebellar ataxia with neuropathy and vestibular areflexia syndrome (CANVAS). Neurol Clin Pract. 2016;6(1):61–8.CrossRefGoogle Scholar
Szmulewicz DJ, McLean CA, Rodriguez ML, Chancellor AM, Mossman S, Lamont D, et al. Dorsal root ganglionopathy is responsible for the sensory impairment in CANVAS. Neurology. 2014;82(16):1410–5.CrossRefGoogle Scholar
Szmulewicz DJ, Seiderer L, Halmagyi GM, Storey E, Roberts L. Neurophysiological evidence for generalized sensory neuronopathy in cerebellar ataxia with neuropathy and bilateral vestibular areflexia syndrome. Muscle Nerve. 2015;51(4):600–3.CrossRefGoogle Scholar
Petersen JA, Wichmann WW, Weber KP. The pivotal sign of CANVAS. Neurology. 2013;81(18):1642–3.CrossRefGoogle Scholar
Wu TY, Taylor JM, Kilfoyle DH, Smith AD, McGuinness BJ, Simpson MP, et al. Autonomic dysfunction is a major feature of cerebellar ataxia, neuropathy, vestibular areflexia ‘CANVAS’ syndrome. Brain. 2014;137(Pt 10):2649–56.CrossRefGoogle Scholar
Strupp M, Kim JS, Murofushi T, Straumann D, Jen JC, Rosengren SM, et al. Bilateral vestibulopathy: diagnostic criteria consensus document of the Classification Committee of the Barany Society. J Vestib Res. 2017;27(4):177–89.CrossRefGoogle Scholar
Rust H, Peters N, Allum JHJ, Wagner B, Honegger F, Baumann T. VEMPs in a patient with cerebellar ataxia, neuropathy and vestibular areflexia (CANVAS). J Neurol Sci. 2017;378:9–11.CrossRefGoogle Scholar
Rey-Martinez J, Batuecas-Caletrio A, Matino E, Trinidad-Ruiz G, Altuna X, Perez-Fernandez N. Mathematical methods for measuring the visually enhanced vestibulo-ocular reflex and preliminary results from healthy subjects and patient groups. Front Neurol. 2018;9:69.CrossRefGoogle Scholar
Guajardo-Vergara C, Pérez-Fernandez N. Air and bone stimulation in vestibular evoked myogenic potentials in patients with unilateral Ménière’s disease and in controls, Hearing, Balance and Communication. 2019; 17: 170-8, https://doi.org/10.1080/21695717.2019.1591009.
Zilliox L, Peltier AC, Wren PA, Anderson A, Smith AG, Singleton JR, et al. Assessing autonomic dysfunction in early diabetic neuropathy: the survey of autonomic symptoms. Neurology. 2011;76(12):1099–105.CrossRefGoogle Scholar
Li C, Layman AJ, Carey JP, Agrawal Y. Epidemiology of vestibular evoked myogenic potentials: data from the Baltimore longitudinal study of aging. Clin Neurophysiol. 2015;126(11):2207–15.CrossRefGoogle Scholar
Oh SY, Kim HJ, Kim JS. Vestibular-evoked myogenic potentials in central vestibular disorders. J Neurol. 2016;263(2):210–20.CrossRefGoogle Scholar
Szmulewicz DJ, Merchant SN, Halmagyi GM. Cerebellar ataxia with neuropathy and bilateral vestibular areflexia syndrome: a histopathologic case report. Otol Neurotol. 2011;32(8):e63–5.CrossRefGoogle Scholar
Manzari L, Burgess AM, McGarvie LA, Curthoys IS. An indicator of probable semicircular canal dehiscence: ocular vestibular evoked myogenic potentials to high frequencies. Otolaryngol Head Neck Surg. 2013;149(1):142–5.CrossRefGoogle Scholar
Zingler VC, Weintz E, Jahn K, Huppert D, Cnyrim C, Brandt T, et al. Causative factors, epidemiology, and follow-up of bilateral vestibulopathy. Ann N Y Acad Sci. 2009;1164:505–8.CrossRefGoogle Scholar
Cortese A, Simone R, Sullivan R, Vandrovcova J, Tariq H, Yau WY, et al. Biallelic expansion of an intronic repeat in RFC1 is a common cause of late-onset ataxia. Nat Genet. 2019;51(4):649–58.CrossRefGoogle Scholar