3D Model to Understand the Diagnosis and Treatment of Horizontal Canal BPPV.

Objective: Our primary objective was to develop a three-dimensional (3D) model of the vestibular labyrinth to understand the pathophysiological mechanisms of benign paroxysmal positional vertigo (BPPV) observed during common diagnostic positional tests. We secondarily aimed to monitor the effects of the repositioning maneuvers and use this tool in teaching.

Methods: A 3D model of a human semicircular canals (SSCs) system was created by 3D printing the core and assembling it with silicone tubing filled with lubricant oil containing colored small stones in the lumen mimicking otoconia. We used the model in horizontal canal BPPV diagnostic tests and therapeutic maneuvers. The working mechanism of the model we designed was recorded with video.

Results: The model allowed for a clear display of the anatomy and the respective orientations of the SSCs. Otolith movement in the horizontal canals could be imitated during diagnostic positional tests (Dix-Hallpike and Pagnini-McClure) and therapeutic maneuvers (Epley, Semont, Lempert and Gufoni).

Conclusion: As well as helping to understand the anatomy and physiology of the SSCs, this simple 3D model also provides a teaching tool for the diagnosis and treatment of BPPV. The mechanism of horizontal canal canalithiasis and the effect of therapeutic repositioning maneuvers could be clearly observed by watching the markers in the lumen demonstrating the progress of otolith movements with changes in head position relative to gravity.