Takeaway
Longitudinal thinning to the retinal nerve fibre layer (RNFL) was faster in patients who converted from relapsing remitting multiple sclerosis (RRMS) to secondary progressive multiple sclerosis (SPMS) than those patients who did not convert.
Why this matters
Diagnosis of SPMS is challenging, which can delay administration of disease-modifying therapies to slow disease progression.
Further investigation of retinal thinning as a potential biomarker for disease progression is needed.