対側型遅発性内リンパ水腫の聴力変動について

Abstract

We treated 42 patients with delayed endolymphatic hydrops (DEH) : 33 ipsilateral, 7 contralateral, and 2 bilateral. We conducted a clinical study of the 7 patients with contralateral DEH.Patients with contralateral DEH have a profound hearing loss in one ear, and eventually develop symptoms of endolymphatic hydrops in the opposite ear (only hearing ear) -fluctuating hearing loss with or without vertigo-, which is a very serious problem not only for the patient but also for otologist.The cause of the profound hearing loss in our 7 cases was head trauma, otitis media and mumps (1 case each), and juvenile unilateral deafness of unknown etiology in 4.The chief complaint was fluctuating and progressive hearing loss in the better hearing ear in 6, and rotatory vertigo caused by the normal hearing ear in 1.In the diagnosis of contralateral DEH, the clinical history is most important and the glycerol and furosemide tests are very useful.In the treatment of contralateral DEH diuretics and steroids have been employed. In those who failed to respond to conservative therapy, epidural shunt operation on the endolymphatic sac was performed in our clinic. The treatment was effective in many cases, but in some cases hearing loss progressed in spite of the intensive therapy. In the patients with advanced hearing loss already in the better hearing ear, it is very difficult to perform an operation because of the relatively high risk of making the hearing worse. We have tried γ-globulin therapy in some patients who showed a poor response to conventional therapy. This therapy sometimes yielded good results. The action of the γ-globulin on the inner ear and the endolymphatic sac is still unknown. But we believe that we should always strive to search for a more effective conservative therapy as well as trying to be more skillful in surgical management.