Dr. Jeslin Johnson

Dr.VIRNA SHAH

Abstract

A 28 year old man with no significant co morbidities or addiction presented with abnormal movement of both eyes noticed for the past 1year .Family history of some nervous system malformation noticed in brother at the age of 26.On central nervous system examination showed no focal neurological deficits or cerebellar signs except for nystagmus. On ocular examination showed bilateral down beat nystagmus .His best corrected visual acuity was 6/6. Anterior and posterior segment examination was within normal.Considering new onset nystagmus MRI brain with contrast was done which showed type 1 Arnold- Chiari malformation . Gaze-evoked nystagmus is the most common type of nystagmus in patients with Type 1 Chiari malformation;it is present in up to 30% of the patients. Downbeat nystagmus is present in 4-6% of patients with type 1 Chiari malformation. In conclusion, we report the association of downbeat nystagmus with Type 1 Arnold-Chiari malformation.