Surgery for acoustic neuromas may involve removing all or part of the tumor.
There are three main surgical approaches for removing an acoustic neuroma:
· Translabyrinthine, which involves making an incision behind the ear and removing the bone behind the ear and some of the middle ear. This procedure is used for tumors larger than 3 centimeters. The upside of this approach is that it allows the surgeon to see an important cranial nerve (the facial nerve) clearly before removing the tumor. The downside of this technique is that it results in permanent hearing loss.
· Retrosigmoid/sub-occipital, which involves exposing the back of the tumor by opening the skull near the back of the head. This approach can be used for removing tumors of any size and offers the possibility of preserving hearing.
· Middle fossa, which involves removing a small piece of bone above the ear canal to access and remove small tumors confined to the internal auditory canal, the narrow passageway from the brain to the middle and inner ear. Using this approach may enable surgeons to preserve a patient's hearing.
A newer, less invasive technique called total endoscopic resection enables surgeons to remove acoustic neuromas using a small camera inserted through a hole in the skull. This technique is offered only at major medical centers with specially trained surgeons. Initial studies show success rates similar to those with conventional surgery.
Radiation therapy is recommended in some cases for acoustic neuromas. State-of-the-art delivery techniques make it possible to send high doses of radiation to the tumour while limiting expose and damage to surrounding tissue.
Radiation therapy for this condition is usually delivered in one of two ways:
· Single fraction stereotactic radiosurgery (SRS), in which many hundreds of small beams of radiation are aimed at the tumor in a single session.
· Multi-session fractionated stereotactic radiotherapy (FRS), which delivers smaller doses of radiation daily, generally over several weeks. Early studies suggest multi-session therapy may preserve hearing better than SRS.