Optic chiasmal neuritis: clinical features, aetiologies, MRI patterns and prognosis in a real-world cohort.
Multiple sclerosis, not neuromyelitis optica, is the leading cause of optic chiasmal neuritis.
Optic chiasmal neuritis: clinical features, aetiologies, MRI patterns and prognosis in a real-world cohort.
Optic chiasmal neuritis (optic chiasmal neuritis) is considered atypical for multiple sclerosis (multiple sclerosis) and more frequently associated with neuromyelitis optica spectrum disorders (neuromyelitis optica spectrum disorders).
We conducted a retrospective single-centre study of consecutive patients with MRI-confirmed chiasmal enhancement between 2017 and 2025.
Eye pain was reported in 58.1% of cases, phosphenes in 14%, and visual symptoms were bilateral in 39.5%.
Orbital MRI patterns differed by aetiology: unilateral hemichiasmal T2-weighted involvement was significantly more frequent in multiple sclerosis than in non-multiple sclerosis patients (74.1% vs 25%, p = 0.004).
Median time to intravenous methylprednisolone was 19 days (IQR 9.8-32.3).
At one year, normal visual acuity was recovered in 55.4% of patients.
To our knowledge, this is the largest real-world cohort specifically dedicated to optic chiasmal neuritis, a rare and heterogeneous inflammatory disorder of the optic pathway.
Contrary to current perception, multiple sclerosis is the leading aetiology in real-world practice, challenging the traditional view of optic chiasmal neuritis as predominantly related to neuromyelitis optica spectrum disorders.
Orbital MRI patterns may help differentiate multiple sclerosis from neuromyelitis optica spectrum disorders and MOGAD, and early recognition is essential given frequent diagnostic and treatment delays.