J Korean Bal Soc.  2006 Jun;5(1):63-69.

Horizontal Canal Benign Paroxysmal Positional Vertigo in Caloric Dead Labyrinth

• Song JJ
• Ahn YH
• Kim JS
• Koo JW

Abstract

The presence of functioning semicircular canal is regarded as a prerequisite for the development of benign paroxysmal positional vertigo (BPPV) since BPPV is irritative vestibulopathy. However, authors experienced a case of horizontal semicircular canal BPPV in which bithermal caloric test and ice water test were compatible with complete canal paralysis. Forty eight year-old man visited ER for sudden onset of vertigo and right hearing loss developed 3 hours and 4 hours ago, respectively. Vertigo was vaguely complained and was floating in nature, which was aggravated with head position change. Initial audiometry showed 110 dB on pure tone averages. Positional test showed horizontal geotropic direction changing positional nystagmus and it was compatible with canalolithias of right horizontal semicircular canal. The results of initial and follow up bithermal caloric tests and ice water test on supine and prone position were compatible with right side complete canal paralysis. This case implies that caloric dead labyrinth may not represent complete absence of the lateral semicircular canal function and also BPPV can be developed even in a condition with minimal functional remaining.

Keyword

Positional vertigo; Caloric test

MeSH Terms

Audiometry
Caloric Tests
Ear, Inner*
Follow-Up Studies
Head
Hearing Loss
Ice
Nystagmus, Physiologic
Paralysis
Prone Position
Semicircular Canals
Vertigo*
Water
Ice
Water