ENDOLYMPHATIC SAC OBLITERATION FOR LARGE VESTIBULAR AQUEDUCT SYNDROME

The objective of this study was to investigate the effects of endolymp hatic sac obliteration for stabilization of progressive hearing loss i n patients with the large vestibular aqueduct syndrome. This was a ret rospective case review conducted at a private neurootologic office in a metropolitan area. Seven ears in six patients were subjected to surg ery for obliteration of the endolymphatic sac in an effort to stabiliz e progressive hearing loss associated with the large vestibular aquedu ct syndrome. The study population was composed of four boys and two gi rls 4-17 years of age. The large vestibular aqueduct was unilateral in two patients and bilateral in four patients. All seven ears demonstra ted progressive sensorineural hearing loss preoperatively. Surgical ti ssue obliteration was performed via a transmastoid approach in seven e ars. The main outcome measure was comparison of pre- and postoperative hearing levels and stability. Magnetic resonance imaging also was per formed in all cases at least 6 months postoperatively to determine pat ency of the endolymphatic sac and vestibular aqueduct. Six of seven ea rs maintained stable hearing during the follow-up period, which ranged from 6 months to 6 years (mean 3.2 years). One patient showed continu ed progression of hearing loss postoperatively. All seven ears demonst rated continued obliteration on postoperative imaging studies. Surgica l obliteration of the endolymphatic sac may stabilize hearing in patie nts with the large vestibular aqueduct syndrome and progressive hearin g loss. These results support the theory of pressure or fluid reflux i nto the labyrinth as a cause of progressive hearing loss in these pati ents.