MANAGEMENT OF THE SMALL ACOUSTIC NEUROMA - A DECISION-ANALYSIS

Imaging techniques such as magnetic resonance imaging (MRI) with gadol inium may detect small acoustic neuromas before significant symptoms h ave developed. In this situation, the patient and surgeon may question whether the tumor requires treatment, especially if the tumor was dis covered incidentally. A computerized clinical decision analysis was un dertaken to model the decision to observe such tumors or proceed to im mediate surgery. The decision tree was constructed with flexibility to account for tumor size, hearing level, and other critical variables s uch as the individual's aversion to unilateral hearing loss and facila paralysis. Unless life expectancy is short, the analysis suggests tha t surgery at the time of diagnosis is appropriate, assuming that growt h of the tumor is anticipated. Variations in surgical proficiency and patient risk aversion within expected ranges do not influence the deci sion to operate. The most critical variable appears to be the probabil ity that the tumor will remain stable in size. This finding suggests t hat better data regarding the growth rate of small acoustic neuromas i s needed.