Document Type : Neuroimage/Video


Department of Neurology, Cruces University Hospital, Barakaldo, Basque Country, Spain


Although the most characteristic symptoms of Miller Fisher syndrome (MFS) are ophthalmoplegia, areflexia, and ataxia, in 1956, Dr. Miller Fisher already described pupillary involvement in some patients. From that moment on, several articles have reported non-reactive dilated or tonic pupils in patients with MFS.1 We report two patients who debuted with
symptoms of dizziness and malaise (Video 1). On examination, the first patient had non-reactive mydriatic pupils and slight limitation for supraversion.
The second patient had nonreactive dilated pupils with weak deep tendon
reflexes. The rest of the examination was completely normal in both cases. In the next few days, patients developed ataxia, areflexia, and ophtalmoplegia. Both patients were diagnosed with MFS. We initiated early treatment with
intravenous immunoglobulin for five days, with both patients recovering fully in less than a month. 


  1. Fisher M. An unusual variant of acute idiopathic polyneuritis (syndrome of ophthalmoplegia, ataxia and areflexia). N Engl J Med 1956; 255(2): 57-65.
  2. Kaymakamzade B, Selcuk F, Koysuren A, Colpak AI, Mut SE, Kansu T. Pupillary Involvement in Miller Fisher Syndrome. Neuroophthalmology 2013; 37(3): 111-5.
  3. Thomas PD. The differential diagnosis of fixed dilated pupils: A case report and review. Crit Care Resusc 2000; 2(1): 34-7.