Evaluation of the Peripheral Nerve Ultrasound as a Diagnostic Tool in CANVAS (Cerebellar Ataxia With Neuropathy and Vestibular Areflexia Syndrome) Neuronopathies
Evaluation of the Peripheral Nerve Ultrasound as a Diagnostic Tool in CANVAS (Cerebellar Ataxia With Neuropathy and Vestibular Areflexia Syndrome) Neuronopathies
Cerebellar ataxia with neuropathy and bilateral areflexia syndrome (CANVAS) is a late onset neurodegenerative disorder with a slowly progressive ataxia. It's genetic causative etiology with an autosomal recessive inheritance has a recent discovery.
It is clinically characterized by impaired visually enhanced vestibulo-ocular reflex, although patients commonly present with imbalance as a main concern, associated with sensory complaints. It has been demonstrated that sensory impairment in CANVAS patients is due to degeneration of dorsal root with abnormal sensory nerve conduction.
Previously defined diagnostic criteria included cerebellar atrophy on brain MRI, neuronopathy on electrophysiological studies and negative genetic testing for other inherited ataxia syndromes like Friedriech ataxia and spinal cerebellar ataxia (SCA).
Peripheral nerve ultrasound is a noninvasive technique, able to identify abnormal peripheral nerves with underlying injuries and specific sonographic characteristics. Pelosi et al established that patients with CANVAS have a smaller nerve cross sectional area (CSA) compared to healthy individuals and/ or axonal neuropathies.
The main objective of this study was to obtaine a detailed description of peripheral nerves in consecutive patients with CANVAS syndrome followed in theneurology department of the Universitary Hospital of Nimes (France), using conventional electrophysiology and peripheral nerve ultrasound.
CANVAS Patients :
Inclusion Criteria:
Exclusion Criteria:
Control group, inclusion criteria :
Patient with axonal sensory-motor or pure sensory neuropathy confirmed by electro neuromyography, and concordant with the clinic.