The Meniere attack: An ischemia/reperfusion disorder of inner ear sensory tissues
We believe Meniere attacks arise as a chance association of endolymphatic hydrops and vascular risk factors for intracerebral ischemia. Hydrops acts as a variable Starling resistor upon the inner ear vasculature that is capable of inducing ischemic attacks only in people with reduced perfusion pressure in the ear.
The unique characteristics of the attacks (loss of vestibular response and hearing acutely followed by a
return to apparent normalcy over hours) are explained by the differential sensitivity of the inner ear tissues
to transient ischemia, with the sensory tissues (dendrites, hair cells) vulnerable to hours-long ischemia/
reperfusion injury, and the stria vulnerable to ischemia due to its high metabolic rate. Permanent
hearing loss and vestibular damage after many attacks would result when small areas of irreversible sensory cell damage accumulate and become confluent. Leggi tutto