Traumatic Perilymphatic Fistula Presenting with Direction-Changing Positional Nystagmus

ABSTRACT

Diagnosis of perilymphatic fistula (PLF) is considered in the patient presenting hearing loss associated with ataxia after penetrating injury of the tympanic membrane. PLF accompanies mixed type hearing loss and paralytic nystagmus. If audiovestibular symptoms and signs are not definite for those patients, in whom PLF is highly suspicious, they can be induced by affected ear down position. The direction of nystagmus induced by position change was reported either toward or away from the affected ear. But the direction changing nature has not been noted in the previous literature. We report on a case of traumatic PLF presented with direction changing positional nystagmus and discuss the possible mechanism involved in this case