Patients with the genetic disorder von Hippel-Lindau disease may suddenly experience hearing loss because of a tumor-associated hemorrhage in the inner ear, according to a study in the July 4 issue of JAMA.

Endolymphatic sac tumors (ELSTs; tumors of the inner ear) occur sporadically but may be associated with von Hippel-Lindau disease (VHL; a genetic disease characterized by the development of blood vessel tumors in the retina of the eye and in the brain; lesions and cysts can also develop in other parts of the body). ELSTs are associated with significant dysfunction of hearing and balance, including sudden irreversible hearing loss. The mechanisms and appropriate treatments for this disorder are not well understood.

John A. Butman, M.D., Ph.D., of the National Institutes Health, Bethesda, Md., and colleagues conducted a study, between May 1990 and December 2006, to determine the mechanisms underlying hearing loss in patients with ELSTs. Clinical findings and audiologic data were correlated with magnetic resonance imaging and computed tomography imaging studies. Thirty-five patients with von Hippel-Lindau disease and ELSTs in 38 ears were identified.

the most common ELSTassociated clinical finding in this series was hearing loss. Sensorineural hearing loss (SNHL) occurred in 31 patients (89 percent) or 34 of the affected ears (89 percent) and was frequently moderate or profound. Other less frequent ELSTassociated findings included aural [pertaining to the ear or hearing] fullness, aural pain, facial nerve weakness, and aural pain and facial nerve weakness combined, the authors write.

Intralabyrinthine (inner ear) hemorrhage was found in 11 of 14 ears with sudden SNHL but occurred in none of the 17 ears with gradual SNHL or normal hearing. Tumor size was not related to SNHL.

Based on the relationship between the imaging and clinical findings in these patients, 3 distinct mechanisms (either alone or in combinati
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JAMA and Archives Journals
3-Jul-2007