Die Wirkung Methodischer Faktoren Auf Das Mikrophonpotential Der Meerschweinchenkochlea Bei Der Perilymphatischen Perfusion

The influence of perilymphatic pressure on the displacement of the tympanic membrane. A quantitative study on human temporal bones

A model study on human temporal bones was performed. A microflow method was used in order to assess the possibility of making indirect recordings of changes in the inner ear pressures. Changes in the perilymphatic pressure were recorded as displacements of the tympanic membrane, the stapedius reflex being artificially elicited by forces applied briefly to the stapedius tendon. Changes in the perilymphatic pressures in the range of +/-15 cm H2O affected the position of the tympanic membrane and the "stapedius reflex response". The microflow method used seems suitable for the clinical recording of changes in the intralabyrinthine pressure.

Effects of perilymphatic perfusion with neomycin on the cochlear microphonic potential in the guinea pig

The effects of three concentrations of neomycin, administered by a method of acute perilymphatic perfusion of the guinea pig cochlea, on the cochlear microphonic potential (CM) at 4 kHz and 500 Hz are described. A concentration-dependent reduction in CM occured during the 60 minute perfusion period. Neomycin at 10-4 M did not change the CM magnitude, while at 10-3 and 102 M it caused 4 kHz (and 500 Hz) CM reductions which began within 24 (for both frequencies) minutes and 10 (and 12) minutes of drug application respectively. CM reduction proceeded at a higher rate for greater neomycin concentration. The perfusion technique, the implication of the frequency indifference, and the potential of the perfusion technique for inner ear biochemical analysis are discussed.