Evaluation of the Diagnostic Value of Video-oculography in CANVAS Neuronopathies

Completed

• Conditions: Cerebellar Ataxia
• Interventions: Other: None, pure observationnal study

• Registration Number: NCT05278091
• Lead Sponsor: Centre Hospitalier Universitaire de Nīmes

Brief Summary

Cerebellar ataxia syndrome with neuropathy and vestibular areflexia (CANVAS) is a genetic pathology of recent discovery (bi-allelic expansion in intron 1 of the RFC1 gene with AAGG repetition). The clinical picture is protean, associating a neuronopathy, a bilateral vestibulopathy evidenced by an alteration of the oculovestibular reflex (VOR), an atrophy of the cerebellum and a chronic cough.

In the initial stage of the disease the clinical picture is heterogeneous and often incomplete. Ataxia at the beginning of the disease may be the consequence of peripheral nervous system involvement (neuronopathy) and the cerebellar syndrome may manifest itself clinically late.

Eye movement involvement in central nervous system pathologies is common (4). Oculomotor abnormalities are often subclinical and sometimes exclusively identifiable by an instrumental study, video-oculography (VOG) (5).

VOG is a non-invasive examination of eye movements, which is increasingly used in the differential diagnosis of neurodegenerative syndromes (6). This examination allows, among other things, to identify oculomotor anomalies, even discrete and asymptomatic, by studying the combined movements of the eyes and the oculocephalic movements.

The study of oculomotricity by VOG can therefore potentially contribute to the early differential diagnosis of ataxiating neuropathies, including CANVAS, by revealing infra-clinical oculomotor abnormalities correlated with a cerebellar expectation (knowing the role of the dorsal vermis in the precision of saccades and pursuits).

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2022-03-04
• Study First Submitted QC: 2022-03-04
• Study First Posted: 2022-03-14
• Study Start: 2022-03-15
• Primary Completion: 2023-03-15
• Study Completion: 2023-03-15
• Status Verified: 2024-03
• Last Update Submitted: 2024-03-07
• Last Update Posted: 2024-03-08

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 56

Inclusion Criteria

Patients followed at the University Hospital of Nîmes between 2018-2021

• Age > 18 years
• Patients with CANVAS with genetic confirmation (RFC1 gene mutation)
• Patients with axonal neuropathy, autoimmune neuronopathy and anti-MAG neuropathy
• Healthy controls

Exclusion Criteria

Not provided

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Healthy controls	None, pure observationnal study	Patients without CANVAS or other neuropathy
Patients with CANVAS with genetic confirmation	None, pure observationnal study	Patients with CANVAS with genetic confirmation (RFC1 gene mutation)
others patients	None, pure observationnal study	Patients with axonal neuropathy, autoimmune neuronopathy and anti-MAG neuropathy

Primary Outcome Measures

Name	Time	Method
down beat nystagmus	Baseline, Day 0	Comparison of video oculography results (down beat nystagmus) of patients with a diagnosis of CANVAS with those of the other groups
jerky pursuits	Baseline, Day 0	Comparison of video oculography results (saccadic pursuits) of patients with a diagnosis of CANVAS with those of the other groups
gaze evoked nystagmus	Baseline, Day 0	Comparison of video oculography results (gaze evoked nystagmus) of patients with a diagnosis of CANVAS with those of the other groups
rebound nystagmus	Baseline, Day 0	Comparison of video oculography results (rebound nystagmus) of patients with a diagnosis of CANVAS with those of the other groups

Trial Locations

Locations (1)

CHU de Nîmes; 🇫🇷 Nîmes, Choisir Une Région, France