Pjd. Dawes et He. Basiouny, Outcome of using magnetic resonance imaging as an initial screen to exclude vestibular schwannoma in patients presenting with unilateral tinnitus, J LARYNG OT, 113(9), 1999, pp. 818-822
The improved cost-effectiveness of gadolinium-enhanced magnetic resonance i
maging (MRIg) as a diagnostic tool for vestibular schwannoma has resulted i
n smaller tumours being diagnosed. There has been a change in the clinical
presentation of these tumours and up to four per cent may present with unil
ateral tinnitus. The limitation of auditory brain stem response (ABR) as a
screening tool that detects small tumours is recognized and there is a stro
ng argument for using MRIg as the initial investigation.
Various screening guidelines have been proposed, some include submitting pa
tients with unilateral tinnitus for MRIg. This report describes the finding
s in a group of 174 patients presenting with unilateral tinnitus who underw
ent MRIg as part of a guideline-directed screen to exclude vestibular schwa
nnoma. Five patients had a cause for their tinnitus diagnosed, one a vestib
ular schwannoma. Two had intracranial aneurysms and another three had patho
logy revealed that merited onward referral. A further nine patients had inc
idental findings that neither accounted for their symptoms nor needed furth
er investigation or referral.
The rationale for screening these patients with MRIg is discussed.