Affiliations: Department of Bioengineering, University of Utah, Salt Lake City, UT – 84112, USA
Correspondence:
[*]
Address for correspondence: Richard D. Rabbitt, Ph.D., Department of Bioengineering, 20 South 2030 East, Rm. 506 Salt Lake City, UT – 84112, USA. Tel: +1 801 581 6968; Fax: +1 801 581 8966; E-mail: r.rabbitt@utah.edu
Abstract: Horizontal canal (HC) benign paroxysmal positional vertigo (HC-BPPV) is a vestibular disorder characterized by bouts of horizontal ocular nystagmus induced during reorientation of the head relative to gravity. The present report addresses the application of a morphologically descriptive 3-canal biomechanical model of the human membranous labyrinth to study gravity-dependent semicircular canal responses during this condition. The model estimates dynamic cupular and endolymph displacements elicited during HC-BPPV provocative diagnostic maneuvers and canalith repositioning procedures (CRPs). The activation latencies in response to an HC-BPPV provocative diagnostic test were predicted to vary depending upon the initial location of the canalith debris (e.g. within the HC lumen vs. in the ampulla). Results may explain why the onset latency of ocular nystagmus evoked by the Dix-Hallpike provocative maneuver for posterior canal BPPV are typically longer than the latencies evoked by analogous tests for HC-BPPV. The model was further applied to assess the efficacy of a 360°-rotation CRP for the treatment of canalithiasis HC-BPPV.
