Experimental Model of Vertigo Induced by Detached Otoconia

Abstract

Isolated posterior semicircular canals (psc) of bull frogs were used for a model of positional vertigo. Induced ampullary nerve action potentials were recorded. When the cupula was removed and the saccular otoconia were dropped onto the cilia, excitatory, and inhibitory potentials were evoked by changing the psc positions into canal-down and canal-up, respectively. When the otoconia were allowed to stay on the cupular surface, canal-down and canal-up positions also evoked excitatory and inhibitory responses, respectively. When the otoconia were inserted in the canal and were allowed to move, changing the psc positions likewise evoked responses. However, when one end of the canal was closed, these responses disappeared, indicating the efficacy of canal plugging.

Benign Paroxysmal Positioning Vertigo: A Disease Explainable by Inner Ear Mechanics

“…Observations on the frog's vestibular apparatus gave experimental support for the canalith hypothesis [8] .…”

Morphological change of the cupula due to an ototoxic agent: A comparison with semicircular canal pathology

“…This cupular change may also modify the clinical picture of positional vertigo [20]. We need to pay more attention to disorders of the appendicular part of the sensory organs as a possible lesion of peripheral vertigo.…”

Intractable Persistent Direction-Changing Geotropic Nystagmus Improved by Lateral Semicircular Canal Plugging

“…Since the top of cupula attaches to the ampullar wall, an occluded semicircular canal creates a closed space between the cupula and the occluded site. Although the space is surrounded by soft tissue as membranous labyrinth and cupula, the animal study confirmed that this space acts as a solid component and inhibits the compression or expansion of the endolymph; therefore the cupula becomes fixed [ 15 , 16 ]. In other words, successful plugging surgery requires a closed fluid-filled space between the cupula and the occluded site.…”