Experimental endolymphatic hydrops and its relief by interrupting the lateral semicircular duct in guinea pigs.

It has been demonstrated that endolymphatic hydrops can be produced in guinea pigs by obliteration of the endolymphatic sac and this phenomenon was reproduced in our own laboratory. Interruption of the lateral semicircular duct of animals with labyrinthine hydrops produced a diminution of the hydrops in 4 out of 8 cases, and these did not show any collapse in the cochlear duct. It was considered that the hydrops was diminished by drainage of the surplus endolymph into the perilymphatic space, and that the cochlear duct was kept secure from collapse because of its distance from the operated lateral semicircular duct and of the utriculo-endolymphatic valve. Persistence of hydrops in the other four cases was thought to be due to closure of the operated lateral semicircular duct or to labyrinthitis. Although this series is not comprehensive enough, it seems to indicate that interruption of the lateral semicircular duct has a possibility of diminishing labyrinthine hydrops, as in cases of Ménière's disease, without hearing disturbance, provided that complications do not develop. Further investigation with many more animals, for a longer period of time after the operation, is required to gain more precisely detailed information.