A novel vestibulo-cerebellar ataxia, Cerebellar Ataxia with Neuropathy and Vestibular Areflexia Syndrome (CANVAS): clinical phenotype, pathology, imaging, differential diagnoses and a quantitative bedside test

Abstract

© 2014 Dr. David Joshua SzmulewiczPatients with combined cerebellar and vestibular impairment were first identified in about 1979 and were studied as a pathophysiological model. The syndrome of Cerebellar Ataxia with Bilateral Vestibulopathy (CABV) and it’s characteristic oculomotor abnormality, that is, the abnormal visually-enhanced vestibulo-ocular reflex (VVOR) was then subsequently described in 2005 in 4 patients, 3 of whom had a peripheral sensory deficit. Here I set out to establish whether these three patients actually had a totally new, so far undescribed, neurological disease. The work in this thesis defines this new neurological disease that is now called ‘CANVAS’: an acronym for Cerebellar Ataxia with Neuropathy and bilateral Vestibular Areflexia Syndrome. This thesis details the (A) clinical presentation and evolution, (B) essential oculomotor and vestibular abnormalities, (C) neuropathology, (D) otopathology, (E) anatomical pattern of cerebellar atrophy, (F) the neurophysiological characteristics of the somatosensory impairment, (G) differential diagnoses, (H) apparent genetic basis and (I) a diagnostic quantitative bedside oculomotor test