In 1994, as part of our ongoing commitment to bring new medical advances to the region, Sierra Medical Center became the 18th site in the United States - 50th worldwide - to offer Gamma Knife Radiosurgery. Because of the center's location on the U.S. - Mexican border, many international patients come here to take advantage of Gamma Knife treatment and services in a bilingual/bicultural environment.

Your doctor may call upon the skills of a neurosurgeon, radiation oncologist, medical physicist, radiologist and nurse specialist to help treat patients. Once selected as a Gamma Knife candidate, patients and their families receive a tour of the Gamma Knife Suite and meet with the nurse specialist to ask questions and review aspects of the treatment process. Every effort is made to address any concerns patients may have to help ensure their comfort during treatment.

How Gamma Knife Works
At Sierra Medical Center, we understand the uncertainty and fear involved when you or a loved one has been diagnosed with a brain tumor. That's why we've prepared a step-by-step explanation of the Gamma Knife procedure to help ease your concerns and answer any questions you may have about the actual process. Here's how Gamma Knife works:

• Stage 1: Frame Placement
  Using small pins, you will be fitted with a metal frame, called a stereotactic frame, to help define the treatment targets and help prevent your head from moving during treatment. A small amount of local anesthesia is used to minimize discomfort when placing the stereotactic frame on your head.

  The frame is used during treatment planning to determine the precise coordinates of the brain abnormality or tissue that is to be treated.

• Stage 2: Imaging
  Next, you will undergo an imaging study (or studies) to produce several "pictures" of your brain in order to locate the abnormality.

  The imaging study can be conducted using an MRI, CT scan, angiogram or a combination of these tests, depending on the type of abnormality or tissue that is to be treated.

• Stage 3: Computerized Treatment Planning
  Once the studies are completed, the images of your brain are transferred into a computerized treatment planning system.

  Gamma Knife specialists use a computer to determine the exact coordinates of the brain abnormality (or tissue) and to calculate how many "shots" of radiation will be necessary for treatment. This will help to shape the dose of radiation as closely as possible to the size of the abnormality.

• Stage 4: Treatment
  You are now ready for treatment. During your procedure, you will be in constant audio-visual communication with the attending doctors and specialists.

  You will be placed on the Gamma Knife bed and the stereotactic frame attached to your head will be fastened under a large metal collimater helmet.

  Shaped like a large hemisphere, the collimater helmet has many "holes" that receive and guide the gamma radiation beams to the area in the brain that has been selected for treatment.

  Once you have been positioned, the Gamma Knife will deliver 201 beams of radiation to the abnormality or tissue. Individually, each beam is not powerful enough, but at the point where all the beams meet (at the site of the abnormality or tissue) there is sufficient radiation to treat this area.

• Stage 5: Recovery and Discharge
  Once the treatment is complete, the frame will be removed and bandages will be applied to the pin sites. It is possible that you may be admitted to the hospital for overnight observation. You will stay in the nursing unit until you are released from your primary doctor's care.

  You may remove the bandages the evening of your treatment or the following morning. The small pin sites heal quickly and may be washed 48 hours after your Gamma Knife procedure. If some tingling or numbness occurs at the pin sites, it generally stops within a few weeks.

  Follow-up care for Gamma Knife patients includes visits to your referring doctor and to your Gamma Knife doctors. They will monitor your progress through regular evaluations, imaging studies and follow-up tests as deemed necessary.

Forty Years of Research in Sweden
Stereotactic radiosurgery was first invented in 1950 through the joint efforts of Lars Leksell, a Swedish neurosurgeon, and Börje Larsson, a physicist at the Karolinska Hospital and Institute in Stockholm, Sweden. Radiosurgery works by delivering a high dose of radiation to a target area with "scalpel-like precision." The dose is designed to injure or kill the cells or their supporting blood vessels (usually a tumor), while minimizing the effect on surrounding healthy tissues.

Dr. Leksell continued his extensive research and experimentation with stereotactic radiosurgery and finally created an instrument that could deliver such a precise dose of radiation– the Gamma Knife. Supported by more than 40 years of documented research by its inventors, evaluation and clinical use, Gamma Knife has been effectively used to treat thousands of patients around the world for various conditions, including benign and malignant brain tumors, arteriovascular malformations (AVMs) and some functional disorders such as trigeminal neuralgia. Sierra Medical Center introduced the Gamma Knife to El Paso in 1994.

Additional Information For You
Here are two links that can provide you with additional information and resources on Gamma Knife and Stereotactic Radiosurgery.
www.irsa.org - International Radiosurgery Support Association is an independent organization dedicated to providing educational information, emotional support and physician and site referrals on radiosurgery.

www.elekta.com - Elekta, manufacturer of the Leksell Gamma Knife Unit, provides information on clinical outcomes, the treatment process and other stereotactic radiosurgical tools, as well as photos of the Gamma Knife Unit and the actual procedure.