Treatment Options for Acoustic Neuroma
Multidisciplinary Approach of UCSF
At UCSF we offer a wide range of treatment options that can be tailored to the individual patient. These include surgical approaches using intraoperative navigation and neurophysiological monitoring, as well as the most up-to- date stereotactic radiation technology. Every patient evaluated at UCSF is discussed among a team of dedicated physicians to determine the best treatment approach, and a skull base tumor board comprised of otolaryngologists, radiation oncologists, neurosurgeons, and neuroradiologists meets monthly to review complex skull base tumor cases.
Observation
Not every patient needs to be treated right away. Small tumors detected incidentally or associated with very minor symptoms can be observed with interval MRI scans and follow-up audiograms. However, growing tumors that are observed but not treated may cause more problems and may be harder to treat as symptoms progress. Early detection and treatment of growing tumors offers the best chance of long-term cure and functional recovery.
Microsurgery
The goal of microsurgery is to resect as much tumor as possible without injuring the brain and nerves that control facial function, hearing, and balance.
The Retrosigmoid Approach
This approach is used when the tumor is located mostly outside the internal auditory canal and adjacent to the brain stem. It can be effective for hearing preservation and decompressing the brain when a large tumor has grown.
The Translabyrinthine Approach
This is an approach through the mastoid and semicircular canals to the internal auditory canal, where the tumor is found. The translabyrinthine approach provides direct exposure of the tumor without the need to retract normal brain. It is only indicated for patients who have profound hearing loss or very large tumors with a significant intracanalicular component.
The Middle Fossa Approach
This approach has the best record for preserving hearing when resecting tumors less than 2 cm in diameter. This approach is limited to relatively small acoustic neuromas that are mostly in the inner auditory canal and involves the retraction of the temporal lobe to access the tumor from above.
Radiation Treatment
The goal of radiation treatment is to stop tumor growth without injuring the important structures surrounding the tumor. Radiation will not remove a tumor, but may shrink it after time. In general, there is no clear advantage of one modality over the other, but tumors with a specific size and shape may be more effectively treated with one type of radiosurgery or radiotherapy. Accordingly, centers such as UCSF, which have all modalities of radiation treatment available, offer the most comprehensive approach.
Gamma Knife® Radiosurgery
Radiation is delivered in a single session to the tumor from 200 sources that converge precisely on the tumor. By having a lower dose of radiation from multiple sources converge on a single location, normal tissue in the path receives a minimal dose, reducing the chance of radiation injury.
Fractionated Stereotactic Radiotherapy
Radiation is delivered over multiple sessions at a lower dose to decrease the side effects to surrounding nerves. This type of treatment may be useful for patients with large tumors for whom microsurgery or radiosurgery is not possible.
LINAC Radiosurgery
Radiation is delivered in a single session to the tumor. Images of the patient and tumor help localize the specific path of radiation to target the tumor. Because the radiation passes through normal tissue, there is a slight risk of injury to surrounding nerves. At UCSF we use the CyberKnife® to deliver this type of radiosurgery.