Miller Fisher syndrome: toward a more comprehensive understanding

Purpose To review recent knowledge on the clinical features, pathology and pathophysiology, diagnosis and treatment of Miller Fisher syndrome (MFS). Data sources Clinical and laboratory studies on MFS in the past 10 years we re included. Results A viral infection preceded neurological symptoms in 71.8% of MFS pa tients. Typical MFS consists of the triad of ataxia, areflexia and ophthalm oplegia. Other cranial nerves are also involved, which may overlap with lim b weakness in typical Guillain-Barre syndrome (GBS). Lower cranial nerve va riants of GBS, atypical MFS and ataxic neuropathies may overlap, and are th ought of as variant forms of MFS. Recurrence and CNS involvement is found m ore frequently in MFS than in GBS. Antibody to GQ1b, a tetrasyalogangliosid e (GQ1b antibody) which is found in close relation to ophthalmoplegia in MF S, is also associated with Campylobacter jejuni (C. jejuni) serotype Penner 2. This suggests that C. jejuni may induce MFS via the GQ1b structure. The GQ1b antibody may lead to the failure of acetylcholine release from motor nerve terminals, which has been confirmed by clinical neurophysiological re sults. Conclusions Many studies have shown similarities in the pathogenesis of MFS and GBS. However, there are still some differences between them, especiall y in the areas of sensory and CNS involvement. The GQ1b antibody is thought of as one of the key factors in the pathogenesis of MFS, especially with o phthalmoplegia, and it may prove a useful clinical marker in the diagnosis of MFS.