[Focus on MS - visual loss as a cardinal symptom of multiple sclerosis].

Introduction: Visual disturbances are a common presenting symptom of multiple sclerosis (MS), often caused by optic neuritis. This acute inflammation of the optic nerve leads to pain during eye movements, visual impairment and colour vision defects. Optic neuritis can be idiopathic, MS-associated or occur in the context of other diseases such as NMOSD or MOGAD. Diagnosis is based on clinical findings, imaging and visual evoked potentials. Early high-dose corticosteroid treatment can support recovery and improve long-term prognosis.