Longitudinal Evaluation of Ataxia and Brain Structural Changes in RFC1-Related Disorder.

BACKGROUND

The progression of brain damage in CANVAS/RFC1 remains unclear.

OBJECTIVE

To describe longitudinal brain changes in CANVAS/RFC1.

METHODS

Ten RFC1-positive patients and 10 controls underwent 3T-MRI scans 2 years apart. We analyzed cerebral gray and white matter using FreeSurfer and DTI multiatlas, the cerebellum with CerebNet, and the spinal cord with Spinal Cord Toolbox, respectively. Ataxia severity was measured with SARA. Longitudinal changes were assessed using mixed-effect models and Standardized Response Mean (SRM).

RESULTS

CANVAS/RFC1 patients (mean disease duration: 8.5 ± 3.7 years) showed progressive atrophy in the brainstem (SRM:-3.5), left hippocampus (SRM:-2.1), right thalamus (SRM:-2.6), left cerebellar lobules VI (SRM:-1.1) and X (SRM:-0.7), and reduced spinal cord area at C1 and C2 (SRM:-0.7 each). SARA variation showed lower sensitivity (SRM:0.7).

CONCLUSIONS

Patients with CANVAS/RFC1 showed progressive, asymmetrical volume reduction of structures in the brain and spinal cord (C1 and C2), over a period of 2 years, using 3-tesla MRI.