Background Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS; OMIM 270550) is an early-onset inherited neurodegenerative disorder caused by mutations in the SACS gene and characterised by cerebellar ataxia, spasticity and peripheral neuropathy. Retinal changes may also be associated with ARSACS.

Objective To determine the usefulness of optical coherence tomography (OCT) to measure retinal nerve fibre layer thickness in ARSACS.

Methods A full ophthalmological evaluation, including OCT, was performed in a patient with ARSACS in whom we identified two novel SACS mutations. OCT was also performed in family members of the proband.

Results OCT demonstrated marked retinal nerve fibre layer thickening in the proband, and also in two out of the three unaffected carriers.

Conclusions OCT appears to be a sensitive tool for identifying retinal changes even in carriers with SACS mutations. We suggest the use of OCT in evaluating patients with suspected ARSACS.