Rebound Positional Nystagmus as a Peripheral Origin

Abstract

Three cases of rebound positional nystagmus (RPN) are discussed in the present study. In all cases, spontaneous nystagmus was absent in the primary position, but positional nystagmus appeared in the side down position, and then nystagmus in the reversed direction appeared when the patient was returned to the primary position. The characteristics of RPN in the cases we studied were very similar to those of benign positional nystagmus. Tinnitus was accompanied with vertigo in Cases 2 and 3, and the glycerol tests were positive in Cases 1 and 3. There were no other abnormalities of ocular movements, neurological and neuroradiological examinations suggestive of central nervous system disorders indicating that RPN can be ascribed to peripheral lesions. A selective review of the literature is presented.

Key Words:

• positional nystagmus
• peripheral origin