Periodic Alternating Nystagmus from Focal Cerebellar Lesion

J Korean Neurol Assoc > Volume 23(6); 2005 > Article

Journal of the Korean Neurological Association 2005;23(6): 827-829.

국소 소뇌 병변에서 발생한 주기성교대안진

오영미a, 최광동 오선영 박성호 김지수

서울대학교 의과대학 신경과학교실, 동아대학교 의과대학 신경과학교실a

Periodic Alternating Nystagmus from Focal Cerebellar Lesion

Young-Mi Oh

Department of Neurology, Seoul National University College of Medicine, Seoul; Department of Neurology, Dong-a University College of Medicinea, Busan, Korea

Abstract

Periodic alternating nystagmus (PAN) is characterized by a periodical reversal in the direction of the nystagmus. PAN has rarely been reported in discrete cerebellar lesions. We report a patient with PAN from a focal cerebellar lesion, which developed after removal of an ependymoma in the fourth ventricle. The nystagmus decreased upon tilting the head in the direction of the nystagmus. The positional modulation of the nystagmus supports that PAN occurs from an abnormal velocity storage mechanism. KeyWords:Periodic alternating nystagmus, Cerebellum