STERIOTACTIC RADIOSURGERY AND RADIOTHERAPY IN INDIA
What Is Stereotactic Radiosurgery And How Is It Used ?
Stereotactic radiosurgery, also called stereotactic radiotherapy, is a highly precise form of radiation therapy initially used to treat tumors and other abnormalities of the brain. Now radiosurgery is also being used to treat cancer in other parts of the body in a procedure called stereotactic body radiotherapy (SBRT).
Despite its name, stereotactic radiosurgery is a non-surgical procedure that delivers precisely-targeted radiation at much higher doses than Cyber Knife while sparing healthy tissue organs nearby.
Stereotactic radiosurgery relies on several technologies:
- Three-dimensional imaging that determines the exact coordinates of the target within the body
- Systems to immobilize and carefully position the patient
- Highly focused gamma-ray or x-ray beams that converge on a tumor or abnormality radiation
- In some cases, image-guided radiation therapy (IGRT),which uses medical imaging to confirm the location of a tumor immediately before or during the delivery of radiation to further improve the precision and accuracy of the treatment
What Happens Before Treatment?
Because sedation is used during placement of a stereotactic head frame, no food or drink is permitted past midnight the night before radiosurgery. If you are having FSR with a repositionable mask, there are no restrictions. Come to the hospital or outpatient center the morning of the procedure and check in with the receptionist when you arrive. Dress comfortably and bring a book or something else to keep you busy during the waiting periods. You may also bring a friend or a relative with you for company. If you are having SRS, please make arrangements for transportation home as you might feel tired after the treatment; driving is not recommended.
The nurse or radiation therapist will escort you to a patient holding room, where you may need to change into a gown. An intravenous (IV) line is placed in your arm.
How Does This Therapy Work ?
During the planning process, a 3D visualization of the lesion(s) is done using MRI and CT technology. After 3D imaging is complete, the treatment area is defined by a neurosurgeon and radiation oncologist. Next, powerful computers are used to arrange precise high-energy radiation beams to create an optimal treatment plan for each patient. A micro-multileaf collimator (MMLC) attached to a linear accelerator shapes the beams to precisely conform to the shape and size of the targeted lesion(s). Thus, ensuring delivery of an extremely precise dose distribution to the target, while sparing critical normal tissues and structures.
Stereotactic radiosurgery consists of a single treatment session. A rigid frame is attached to the head to ensure beam precision. Patients being fitted with a frame receive local anesthesia at stabilization sites. Radiosurgery patients should plan on being at the hospital for an entire day, arriving in the early morning and leaving early evening. The frame is removed prior to the patient’s discharge home.
Stereotactic radiotherapy consists of two or more treatment sessions. A treatment stabilization mask, contoured to the patient’s head and face, is used when multiple treatment sessions are required. This is a non-invasive procedure. Patients do not require any anesthetics for treatment planning or during treatment sessions. Radiotherapy patients are treated with lower fraction doses for shorter time periods per session over several weeks. Each treatment session lasts approximately 30-minutes.
The procedures generally cause only minor discomfort and patients usually experience minimal side effects. Patients typically are treated as outpatients and are required to have an escort home.
What Are The Risks ?
Side effects vary depending on the tumor type, total radiation dose, size of the fractions, length of therapy, and amount of healthy tissue in the target area. Some side effects are temporary and some are permanent. Generally, patients may experience fatigue, skin irritation around the target area, and hair loss.
On rare occasions, the radiation dose can cause a buildup of dead tumor tissue, called radiation necrosis, several weeks to months after treatment. Dead or necrotic tissue can become toxic to surrounding normal tissue, and swelling may occur. Brain swelling causes headaches, seizures and confusion. Treatment for radiation necrosis may include steroid medication, hyperbaric oxygen treatments or surgical removal.
Most patients resume normal daily activities, such as work or school, within two to three days. Patients are usually discharged home within hours after receiving stereotactic radiosurgery or radiotherapy. However, if medically necessary, patients may be required to stay in the hospital over night for observation.
While no procedure is risk free, the risks of this procedure vary with the location and size of the lesion. Follow-up with our team of radiation oncologists and neurosurgeons along with other appropriate physicians, along with appropriate follow-up scans, such as, MRI or CT brain scan, are routine, to ensure close monitoring and quality of care.