Your Neurosurgeon, Neurologist, Oncologist or General Practitioner can refer you for treatment. Once the referral is received, a review of the diagnostic information is performed and your case will be discussed at the Alberta Radiosurgery Centre's multidisciplinary rounds.
If appropriate for treatment, you will then have a consultation with the radiation oncologist, neurosurgeon and nurse. At this time, you will be registered with ARC, your treatment plan will be discussed, side effects reviewed, consent forms signed and additional teaching provided. The nurse will also ask you if you've had any allergic reactions to contrast dye in the past, as this dye may be used for the CT on the day of the procedure. This appointment generally takes about 1 hour. Treatment will then be scheduled at an appropriate time. With some conditions we may suggest waiting or repeating imaging instead of treatment immediately.
At the beginning of treatment, a metal head frame is placed on your head. The head frame is designed to restrain the head during treatment and to hold reference markers in a fixed position in relation to the tumor or lesion. The frame is attached to your skull using 4 pins. The pins go through the first couple layers of skin and into the outer part of the skull. A liquid that turns into a gas is sprayed on your head to numb the area; this anesthetic has a strong odor. At this point, a longer lasting local anesthetic is used at the pin sites. The local anesthetic has a burning sensation initially, described as a "wasp sting" sensation, but within minutes your scalp will feel numb. The frame is not painful but feels tight and heavy.
For patients having their treatment over a number of days (fractionated treatments), a face mask is used instead of the metal head ring. Each face mask is custom-made and individually formed. Constructing the face mask is completely painless and typically requires no anesthetic. In addition, you will lie on a custom-made body cushion. This cushion is patterned to your exact body shape to ensure accurate positioning during treatment. It does not interfere with breathing or restrict you in any way. The body cushion does not require any hardware, incisions or painful procedures.
After the head frame or face mask is secured, the localization box is attached and you will be taken to the CT Simulation area. You will have an IV started so that the imaging contrast dye can be used. Inform the nurse if you have had any allergic reaction to contrast dye in the past. You will then be positioned in a treatment position based on temporary skin marks and wall lasers and a CT scan of the target area will be done. The images are automatically downloaded to the Novalis Body workstation. These images show your actual position. In some instances an angiogram will be performed with the head frame in place in the adjoining Foothills Hospital X-ray Department.
After imaging is complete, the localization box is removed. Novalis software automatically calculates a Digitally Reconstructed Radiograph or DRR corresponding to the CT scan. The resulting DDR indicates how the x-ray images will look when you have been perfectly aligned for treatment. A customized treatment plan is then developed based on your specific information. Once the customized treatment plan is completed, a series of carefully controlled quality checks using precise Novalis instruments are done in order to ensure that the shaped radiation beams will be guided precisely to the defined target position.
To begin treatment, you will be taken to the treatment room and positioned comfortably on the specially designed firm couch. Next, the head frame or mask will be secured to the table so your head will not move during the procedure.
Once treatment begins, the Novalis unit will move around you, delivering the prescribed dose of radiation. You will not feel any sensations during the treatment. The machine makes some noises while the treatment is being given. You will be in the room by yourself during the treatment but will be monitored closely using closed circuit TVs and intercom systems. The treatment takes about 30-45 minutes.
Once the treatment is completed, the head frame will be removed and you are free to go home.
You should carefully clean around the pin sites and apply antibiotic ointment to the pin sites to optimize healing for the first few days after treatment. You should not wash your hair for at least 24 hours after the metal head frame is removed, but may do so normally after that.