Drainage Operation in Cases of the Hydrops of the Labyrinth and its Influence on Hearing

A Historical Perspective on Surgical Manipulation of the Membranous Labyrinth for Treatment of Meniere's Disease

Meniere's disease is an inner ear disorder without a known cause. Endolymphatic hydrops is a swelling of the endolymph spaces that has been observed consistently on post-mortem histology in patients with a history of Meniere's disease but can occur in asymptomatic individuals and in association with other diseases. Since its discovery, Meniere's disease has been a disorder managed primarily by otolaryngologists. Surgical treatments, therefore, have accompanied attempts at medical management. Inspired by patients' sensations of ear fullness and later by the histologic findings of hydrops, surgeons began manipulating the membranous labyrinth to relieve episodes of vertigo while attempting to preserve hearing. This review highlights this history of manipulation of the membranous labyrinth. These procedures indicate a rich history of innovation that parallels developments in otologic surgery. The studies involving patients are uniformly retrospective, with some procedures performed first in animal models of endolymphatic hydrops. Many approaches were endorsed by eminent otologic surgeons. Surgeries on the endolymphatic sac are performed by some surgeons today; however, procedures on the membranous labyrinth resulted in similar symptomatic relief through a minimally invasive technique, in many cases performed using only local anesthetic. Episodic vertigo in patients with Meniere's disease is a distressing symptom, yet spontaneous remissions are common. The reports of procedures on the membranous labyrinth reviewed here consistently indicated fewer vertigo episodes. Variable degrees of hearing loss were common following these procedures, and many were abandoned. Additional innovative surgeries are inevitable, but we must understand better the relationships among endolymphatic hydrops, Meniere's disease pathophysiology, and patient symptoms.

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.