Radiation preplanning, also called simulation, is an important step that’s executed prior to starting actual cancer treatments. So why exactly am I showing a picture of spaghetti?
Radiation preplanning, or simulation, is important because the oncology team needs to know exactly where and how big the tumour is in order to help them determine the best treatment plan for you. It’s also important that, during treatment, you are positioned in exactly the same position as you were during the pre-planning stage so that the radiation treatment is focussed exactly where it needs to be. It’s also very important that you remain extremely still during treatments so that you don’t cause the treatment to be accidentally focussed on anything else but your tumour. It’s called simulation because the preplanning team simulates the body position you’ll hold during actual treatment.
Preplanning consists of a few steps: the making of a custom mask, getting a tattoo, and a CT scan.
(I get a tattoo and a swear word bracelet? This isn’t the Sandi that everyone thought they knew 😉 )
The preplanning team started by setting up an IV so that they could inject a radioactive contrast dye intravenously. This helped to show the tumour more clearly in the imaging. Unfortunately, the preplanning team went through my vein initially instead of into it, resulting in a large very black bruise that remained very dark for several weeks.
I was then ushered into the imaging room, towing my IV stand with me, where I was asked to lie down on a very narrow bed. After removing my glasses and untying the bow holding my lovely hospital gown closed (so much for modesty) I managed to get into position, not unlike trying to get into a tippy canoe.
Three people pushed and pulled me into the desired position. My head had to positioned “just so” on the specially shaped head rest up close to the actual scanner, I had to be centred on the bed, and then lined up with a laser beam. Pillows were placed beneath my knees for comfort.
“Don’t move” they said. “Good luck” I said, clutching the sides of my tippy canoe.
Then came the fun part, the making of the custom mask. The preplanning team started by soaking a plastic-like mesh in warm water so that it could be made soft and pliable. It was placed over my entire face and shoulders, and then, working quickly before it could cool, the preplanning technicians stretched it and patted it into the contours of my face, neck, and shoulders. This process felt as though a plate of warm spaghetti was covering my face. Not that I’d know what spaghetti feels like on my face, but it’s what I imagine it would feel like. It wasn’t entirely uncomfortable but it was a bit icky, and I could breathe easily because it was mesh, but I did have to lie perfectly still and keep my eyes closed while the mask was being formed.
Once the mask cooled it hardened, and the technicians then clamped it to the sides of the bed. I was completely immobilized. I couldn’t move, open my eyes, or talk. I could only swallow, and I could wave my hand if I needed help. I remember feeling pity for anyone who suffers from claustrophobia having to endure that.
A small, black dot (not much bigger than a pin head) was tattooed onto the middle of my lower rib cage. It was there so that I could be lined up during radiation treatment in precisely the same position as this simulation step. One of my sisters, who also endured radiation treatment, jokingly asked if they could make her tattoo a sunflower or ladybug. I tried the same ploy, but apparently my preplanning team didn’t have much of a sense of humour.
Next came the CT scan itself. A test scan is done, then the dye is injected. I was warned that it could make me feel like I was peeing. I didn’t get that sensation exactly, but it did make me feel warmish all over. After the dye is injected, the actual scan was done. The “tippy canoe” bed slides inside the large round scanner. I remember it being very breezy and wishing I had a warm blanket (hospital gowns don’t provide much warmth.) The final scan would be used by the preplanning team, radiation technicians, and oncologists to analyze the tumour size and location in order to determine the best radiation plan for me, according to known best practices. The plan was then put in front of a cancer care board for approval.
The bed slides back out, I’m helped off the bed, the gown gets tied back up, my glasses are retrieved, the IV is removed, and then I wait for my first treatment date.
I actually had to go through 3 separate preplanning sessions. The first was in Barrie when I was originally going to be treated there, and the second was at Sunnybrook hospital in the cancer centre. They needed to do their own preplanning because the first preplanning was for esophageal cancer, whereas Sunnybrook was treating me for head and neck cancer.
The third time was also at Sunnybrook, but for a very happy reason. The custom mask that was created for me was becoming too loose and shims were necessary to keep it tightly in place, and so I needed a new mask. It indicated that the tumour was shrinking, confirmed by the CT scan during that last preplanning step! Hallelujah!
Next: my first visit at Sunnybrook
Image courtesy of Suat Eman at FreeDigitalPhotos.net