耳鼻喉学课件：01 耳解剖大课.ppt

前庭阶起自耳蜗的底转卵圆窗，顶端是蜗孔，与下方的骨阶相连。骨阶止于圆窗。 * Reponse is weakened or disappearing for repeated stimuli. * It maintains several weeks or more longer. * The scala vestibuli begins at the base of the cochlea in the area of the oval window. At the apex of the cochlea it is connected to the scala tympani by the helicotrema（蜗孔）. The scala tympani lies below the basilar membrane. It is also filled with perilymph and runs downward from the helicotrema to the round window. Vestibular system/How to keep balance? Physiology Vestibular system/Mechanism of balance control Physiology Vestibular system/Mechanism of balance control Physiology Peripheral system Central system Balance Vestibular system Visual system Proprioception system Vestibular Sensory Organ Physiology Vestibular Sensory Organ Physiology Semicircular canals angular acceleration Ewald laws Vestibular Sensory Organ Physiology Otolith organs Linear acceleration cupulolithiasis canalithiasis Vestibular Pathways Physiology VOR (Vestibular Ocular Reflex) Eye movement compensating Rotation of the head to the right side will enable to maintain fixation of object by movement of the eyes towards the left side. Nystagmus Physiology Involuntary movement of the eyes in horizontal, vertical or rotatory plane Conventionally described by the direction of the fast phase Vestibular system Fatigue: reduction or disappear Physiology Dix-Hallpike maneuver：posterioranterior semicircular canal Vestibular system Vestibular habituation: reduction of the response Physiology Vestibular system Vestibular adaptation: VOR 、vestibular plasticity Physiology The VOR system adjusts the stimulus of any change to obtain the best VOR . Vestibular system Compensation Physiology Replacement of spontaneous activity within vestibular nuclei Electric otoscope Ear endoscope Frontal mirror examination general examination Eustachian tube Complete tympanic membrane Swallowing test Eustachian tube inflation Valsalva method Politzer method Catheteri