Outcome of using magnetic resonance imaging as an initial screen to exclude vestibular schwannoma in patients presenting with unilateral tinnitus

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.