[Flow kinetics of endolymph in rotational stimulation].
In this paper, experimental and mathematical results are presented, indicating rotatory nystagmus to be caused by endolymph flow in the ampulla of the horizontal semicircular canal. During positive or negative acceleration circular flows may develop within the endolymph system, especially in the ampulla of the horizontal semicircular canal. While being independent of the position of the axis of the horizontally rotating system, the velocity of the flow depends on the radius of the establishing "whirl" in the ampulla. It is demonstrated that, close to the corresponding angular acceleration threshold, the velocity of the tangential flow along the cupula is in the same range as that calculated for a caloric stimulus. Like in our model of calorisation also in rotation there is strong evidence that an endolymph flow directed from crista to cupula in the lateral part of the ampulla causes a nystagmus towards the corresponding side, whereas a flow from cupula to crista causes a nystagmus in the opposite direction. Our results suggest that endolymph flows, evoked either by calorisation or rotation, represent adequate stimuli for vestibular excitability.
Pau
H W
HW
HNO-Klinik des Universitäts-Krankenhauses Hamburg-Eppendorf.
Limberg
W
W
D000054:Acceleration; D002150:Caloric Tests; D004710:Endolymph / Q000502:physiology*; D006801:Humans; D007761:Labyrinthine Fluids / Q000502:physiology*; D008953:Models, Anatomic; D009760:Nystagmus, Physiologic / Q000502:physiology*; D012027:Reflex, Vestibulo-Ocular / Q000502:physiology*; D012399:Rotation; D014722:Vestibule, Labyrinth / Q000502:physiology
Strömungskinetik der Endolymphe bei rotatorischer Reizung.