Indications for hearing preservation in acoustic tumor surgery

This study addresses the problem of how to counsel patients with acoustic tumors concerning the issue of hearing preservation. Rather than the traditional yes or no answer, we wish to give the patient the probability that hearing can be preserved given the size of the tumor and the patient's preoperative hearing level. The subjects were 77 patients of the Seattle Ear Clinic who underwent total removal of unilateral acoustic tumors with attempted hearing preservation using a suboccipital approach. Other criteria for inclusion in the study were: tumor size, measured from a preoperative diagnostic image, and availability of pre- and postoperative hearing test results. We reviewed published data from other centers using similar inclusion criteria to determine if our findings were representative of the experience of surgeons at other institutions. We found a significant relationship between hearing preservation success and tumor size, but not between success and preoperative hearing level. The probability of success varied from 78 percent for 0.5-cm tumors to about 15 percent for tumors 2.0 cm and larger. If surgery was successful, 82 percent of patients had hearing that was the same or better than their preoperative hearing level.