title: Role of air contrast computed tomography in diagnosis of small acoustic neuromas.
abstract: Small acoustic tumors occasionally cannot be diagnosed on standard radiologic studies. Over a 2-year period, air contrast computed tomography (CT) has been used to study 22 patients in whom audiologic and vestibular tests suggested a tumor but no radiologic abnormality could be demonstrated; 8 air contrast scans were positive and subsequent exploration revealed tumors in 7 of these patients. In one patient an aneurysmally dilated anterior inferior cerebellar artery was found on exploration. Thirteen scans showed air filling the internal auditory canal with no evidence of tumor. One scan was nondiagnostic and upon exploration, a vascular loop in the internal auditory canal was found. Air contrast high resolution CT is the most accurate method available for detecting small acoustic neuromas. Indications for this technique are discussed along with general approaches to these patients.
mesh_terms: D000328:Adult; D000368:Aged; D000388:Air; D003287:Contrast Media; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media