OCULAR MYASTHENIA - A PROTEAN DISORDER

Ocular myasthenia is a localized form of myasthenia clinically involvi ng only the extraocular, levator palpebrae superioris, and/or orbicula ris oculi muscles. Ocular manifestations can masquerade as a variety o f ocular motility disorders, including cranial nerve and gaze palsies. A history of variable and fatiguable muscle weakness suggests this di agnosis, which may be confirmed by the edrophonium (Tensilon) test and acetylcholine receptor antibody titer. Anticholinesterases, corticost eroids and other immunosuppressive agents, and other therapeutic modal ities, including thymectomy and plasmapheresis, are used in treatment. As the pathophysiology of myasthenia has been elucidated in recent ye ars, newer treatment strategies have evolved, resulting in a much more favorable prognosis than several decades ago. This review provides hi storical background, pathophysiology, immune-genetics, diagnostic test ing, and treatment options for ocular myasthenia, as well as a discuss ion of drug-induced myasthenic syndromes.