Stereotactic Radiation

Stereotactic radiotherapy is a process of delivering radiation to a tumor while minimizing radiation exposure to surrounding structures. This treatment modality is available for managing a number of conditions. In particular, it is offered as a means to treat acoustic neuroma, glomus tumors, and meningioma – all benign (non-cancerous) tumors involving the complex anatomy of the lateral skull base (bone underlying the brain and surrounding the ear structures and brainstem).

Unlike radiation utilized for treating cancer, stereotactic radiation for benign tumors is designed primarily to stop tumor growth by damaging the tumor cells and supporting blood vessels. Minor tumor swelling is expected immediately after treatment, which resolves in a few months. Patients with irradiated tumors will require lifelong follow up with MR to ensure tumors don’t grow at some point in the future. Radiation is successful for arresting tumor growth in over 95% of patients for a period of 5-10 years. Beyond that period of time, tumors in up to 15% of irradiate patients may begin to exhibit breakthrough growth. The risks of this treatment depend upon the type of tumor to be treated, its size, and its location with respect to other key anatomical structures such as the organs of hearing and balance.

Stereotactic radiation is administered via two systems: Gamma Knife Radiosurgery or Cyberknife Radiation. Neither treatment modality requires surgery; however, the Gamma knife system utilizes a head frame fixed to the skull and Cyberknife uses a mask that is molded to the face. Fixation of the head is required to ensure the overall radiation dose, administered via hundreds of less damaging smaller doses, is directed to a single ‘hot spot’ centered and contoured to the tumor. In this manner, healthy surrounding tissues get smaller and less-damaging radiation dosage. Gamma Knife radiation is administered in a single session lasting 2-5 hours while Cyberknife radiation is typically delivered over 3-5 single day sessions in a one week span (call fractions).

Both Dr. Stevens and Dr. Whitaker are certified to participate in the planning and administration of both Gamma Knife and Cyberknife stereotactic radiation. When considering treatment options for your tumor, our doctors will spend dedicated time discussing the pros and cons of every applicable therapy including observation, radiation, and microsurgical resection. Treatment plans will be highly customized to individual patients and account for the patient’s age, overall health, occupation, and personal preferences. To ensure excellent care is delivered to each and every one of our patients, Dr. Stevens and Dr. Whitaker are proudly team with radiation oncologists and other specialists at several treatment centers in the Phoenix Metropolitan area. These include Phoenix Cyberknife and the world renowned Barrow Neurologic Institute.