Relative value of diagnostic tests for small acoustic neuromas

Auditory brainstem response is now widely employed as a screening test for acoustic neuromas because it is equally sensitive when standardized against computed tomography. We have detected eight small (<10 mm) acoustic neuromas using gadolinium enhanced magnetic resonance imaging. In three of these cases, the auditory brainstem response was falsely negative. In contrast, 19 patients with larger tumors (≥10 mm) were found to have no false negative auditory brainstem responses. Auditory brainstem response appears to be less sensitive for detecting small, symptomatic acoustic neuromas.