Miller Fisher syndrome is a rare, acquired nerve disease that is considered to be a variant of Guillain-Barré syndrome. It is characterized by abnormal muscle coordination, paralysis of the eye muscles, and absence of the tendon reflexes. Like Guillain-Barré syndrome, symptoms may be preceded by a viral illness.Miller Fisher syndrome (MFS) is a subgroup of a more common — yet still rare — nerve disorder known as Guillain-Barré syndrome (GBS). While GBS affects just 1 person in 100,000, MFS is even more uncommon. It makes up just 1 to 5 percent of Guillain-Barré cases in the Western world.It is a rare acquired nerve disease related to Guillain-Barré syndrome (GBS). ... It is an autoimmune disease, in which the immune system attacks the nerves. Specific treatment is available but most patients recover within six months even without treatment.