The most common option involves microsurgery, in which the tumor is surgically removed. The tumor is accessed through one of three approaches (translabyrinthine, retrosigmoid [suboccipital], or middle cranial fossa). The selection of the approach is based on tumor size and location, as well as the amount of hearing that the patient has before surgery.
Microsurgery is performed using high-powered microscopes and delicate surgical instruments. The surgery usually lasts between 4 to 12 hours and involves an experienced neurosurgeon and otolaryngologist (neuro-otologist) team who perform the surgery together. Hospital stays range from four to seven days, with an average of four to six weeks recovery time.
The second surgical option is radiosurgery, or stereotactic radiation therapy, a non-invasive procedure that uses high-dose-rate radiation to destroy the tumor. Unlike conventional radiation therapy, in which multiple doses of radiation are delivered over several weeks of treatment, radiosurgery involves only a single dose-delivered to the precise location of the tumor.
The third option is fractionated radiosurgery, in which multiple fractions of radiation-delivered at varying angles-are focused on the tumor site. The Froedtert & the Ϲ Neuroscience Research Center is the first in Wisconsin to have advanced Gamma Knife technology available for this use. The Gamma Knife unit is the world standard for superselective irradiation of tumors and uses advanced imaging technology to identify the exact size, shape and location of the tumor. Once the tumor has been pinpointed, the Gamma Knife directs 201 converging beams of radiation on the site, sparing adjacent tissue of clinically significant radiation.
An important characteristic of the Acoustic Neuroma Program is that a surgical team approach is used not only for the microsurgical removal of tumors but also for the stereotactic radiosurgical treatment of tumors.
This collaborative approach utilizing the expertise of a neuro-otologist and neurosurgeon team is designed to enhance clinical outcomes.
In addition to the Gamma Knife, the surgical team has access to a LINAC-based radiosurgery system. In this system, a relocatable, mask-based, stereotactic head ring is used to direct the fractionated radiation beams. The system uses the same stereotactic localizing technique as used for Gamma Knife treatments, thereby assuring that the radiation dose tightly conforms to the shape of the targeted tumor. The fractionated LINAC-based system is typically used for tumors that are too large to be treated using Gamma Knife technology.
All three surgical options are available within the Froedtert & the Ϲ Neuroscience Center. Medical and surgical specialists are available to consult with patients and help them choose the most appropriate treatment option.