Friday - Radiation Therapy (RT) planning

Today, Robin also had the second meeting with the Radiation Therapy (RT) staff. At the first meeting the RT folks had taken images to create a three dimensional representation of Robin's head in a computer. A Dosimetrist and a Physicist then planned how to position the radiation beams to deliver the prescribed dose of radiation to the tumor, while limiting the amount of radiation which would pass through sensitive organs (eyes, larynx, throat, brain, etc.). They can specify the beam placement within millimeters!



The photo shows Robin standing in front of the Radiation simulation machine (identical to the treatment machine but without the radiation generator). The beams are so small and so precise that they will need to ensure Robin's head is held in the same position each day. In the center of the photo mounted to the table is the white mesh mask which was shaped to Robin's face and which will ensure that she can't move at all when the radiation is applied. The mask is made of plastic so the beams can pass through it, but it's perforated so it's not claustrophobic.

The term "radiation" often makes people think of radioactivity, the process by which an atom splits and spontaneously releases particles. These machines don't use that process - so there is no chance that Robin will become "radioactive"! This machine is much more like a super strong x-ray machine. If it delivers too much energy to a patient it could burn or scar the patient's body. That's why the RT team is so careful in planning the beam trajectory and positioning the patient on the table!