Acoustic Neuroma

Studies of Gamma Knife™ Treatment of Acoustic Neuromas

Comparison of Microsurgical Resection and Stereotactic Radiosurgery
Neurosurgery, July 2006
Abstract
A study compared results for 36 patients who underwent surgical resection to treat unilateral unoperated acoustic neuromas with 46 patients who underwent radiosurgery to treat unilateral unoperated acoustic neuromas. All tumors were less than 3 cm. No difference in tumor control was found but those who underwent radiosurgery did not report the health declines (such as decreased physical function, low energy, or pain) that some who underwent surgical resection reported. They also had less dizziness. Mean follow-up was 3 and a half years.

Enlargement of Acoustic Neuromas after Stereotactic Radiosurgery
Neurosurgery, February 2006
Abstract
A study of 208 patients who underwent stereotactic surgery to treat unilateral acoustic neuromas found that tumors had enlarged at least 2 mm in 14 percent of patients at a median follow-up of 54 months. In the patients with enlargement who did not undergo additional surgery, tumors eventually regressed in 57 percent, remained larger but did not progress in 29 percent, and progressed in 14 percent. (This means that of the total patients who underwent stereotactic surgery, tumors progressed in only two percent.)

Patient Choice in Treatment of Acoustic Neuromas
Otolaryngology – Head & Neck Surgery, May 2004
Abstract
A study of 139 patients over the course of two years (2000 and 2001) found that 23 percent chose watchful waiting, 36 percent underwent stereotactic radiosurgery and 40 percent underwent microsurgical removal.

Lower Radiation Dose Lowers Risk of Facial Neuropathy
International Journal of Radiation Oncology * Biology * Physics, January 1999
Abstract
A study of 82 patients treated with radiosurgery for acoustic neuromas found that reducing radiation dosage significantly lowered the postsurgical risk (from 38 percent to 8 percent) for permanent facial neuropathy.