The Prevalence of “Incidental” Acoustic Neuroma

Abstract

To estimate the prevalence of "incidental" acoustic neuromas (ANs) in the population at large.Design: An intracranial magnetic resonance imaging (MRI) database of 46414 patients presenting to the University of California, San Francisco (UCSF), without known audiovestibular complaints was searched retrospectively from July 1995 to February 2003. Seventy percent of these MRIs included gadolinium, and none was specifically targeted through the internal auditory canal. A medical chart review of 688 patients with acoustic neuromas presenting to UCSF between 1980 and 1999 was searched for sex distribution.Setting: Tertiary care university medical center.Results: Eight patients with incidental AN were discov-ered. This figure suggests that undiagnosed ANs may be present in at least 0.02% of the population. Three patients were found to have audiovestibular symptoms on inquiry after diagnosis. Audiometry revealed asymmetry at 4 kHz in only 3 of 7 patients, with an otherwise symmetric audiogram in the remaining patients. Tumor size in this population ranged from 3 to 28 mm. Incidental ANs were more common in men, but ANs were more common in women overall. Conclusions:The prevalence of incidental AN appears to be roughly 2 in 10000 people. This figure indicates that AN may be less prevalent than suggested in previously reported temporal bone studies and more prevalent than suggested by epidemiologic studies.

Cochlear implantation improves hearing and vertigo in patients after removal of vestibular schwannoma

“…Surgical approaches include the translabyrinthine, the retrosigmoid/suboccipirtal and the middel fossa approach and the mortality rate is lower than 2% 6 . Due to incidental diagnosis of asymptomatic lesions after widespread use of MRI, the incidence appears to be increasing 7 .…”

Calidad de vida tras la cirugía del schwannoma vestibular

“…Por otra parte, el empleo sistemático de la resonancia nuclear magnética (RNM) ha permitido el diagnóstico de tumores cada vez más pequeños, incluso de pequeños tumores intracanaliculares completamente asintomáticos 16 aumentando el número de pacientes con diagnóstico de SV. Lin y cols 17 encontraron una incidencia radiológica (porcentaje de pacientes a quienes se pide una RNM por otra causa y aparece un SV incidental) de 9 casos de SV en 46.414 RNMs. Por lo tanto, actualmente se diagnostican tumores que probablemente permanecerán sin crecer durante toda la vida del paciente.…”

Vestibular Schwannoma and Ipsilateral Endolymphatic Hydrops: An Unusual Association

“…VS have a prevalence of 1.4-2.1 in 10.000 people 2,3 , and represent 5% to 10% of all intracranial tumors, and 80% to 90% of neoplasms of the cerebellopontine angle 4 . VS presenting symptoms usually include slowly progressive sensorineural hearing loss, fullness and tinnitus associated to vestibular disorders in 16-70% of cases; balance disorders can present with acute rotatory vertigo and/or dizziness 5,6 .…”