[Two cases of incomplete Fisher syndrome with unilateral ophthalmoplegia as the main symptom]

Fisher syndrome (FS) is characterized by acute extraocular muscle paralysis, ataxia, and absent tendon reflexes, along with positive anti-GQ1b antibodies. However, incomplete forms of the syndrome, in which only some of the symptoms are present, are known to exist. In this report, we present two cases of incomplete Fisher syndrome with unilateral ocular motor dysfunction. Both patients were positive for anti-GQ1b antibodies and exhibited mild ataxia as the only other neurological symptom, but improved without treatment intervention. This case report highlights the need to recognize that incomplete forms of this syndrome, presenting with unilateral ocular muscle paralysis, exist within the disease spectrum.