Abstract
The pressure difference between perilymph and endolymph in guinea pigs with endolymphatic hydrops was investigated one month after surgical obstruction of the endolymphatic sac and duct.
Pressures were measured with a servo-nulling system (WPI micropressure system model 900). A glass micropipette was inserted into the perilymphatic space through the round window membrane to measure the perilymphatic pressure, then the micropipette was inserted more deeply through the basilar membrane to measure the endolymphatic pressure.
There was no significant pressure difference between the perilymph and the endolymph in guinea pigs with endolymphatic hydrops. Reissner's membrane may be distended very easily when the endolymphatic volume is increased, and it is not stiff enough to maintain the pressure difference between the perilymph and the endolymph.
