Radiation Simulation

Today I went in for the radiation simulation. This involved making a “mask” that will fit over my face and neck that will be bolted to the table during each radiation treatment. That will assure the doctor that my head will be in the same position each and every time. It's important to make sure my head is in the same orientation because my radiologist wants to make sure she's irradiating the same spots each time. There's a lot of stuff going on in and through your head and neck – arteries, nerves, muscles, glands – that shouldn't be irradiated. They're all very close to together and moving even a half centimeter means that something could get cooked that shouldn't. Not all radiation treatment requires a mask, usually just the head and neck regions.

My simulation took about an hour altogether and was even documented by Leslye. She's a dedicated Scrapbooker and I'm convinced she'd take pictures of dog poo if she thought she could get a scrapbook out of it.

The whole operation takes place on the bed of a CT scanner. The object of the game is to get a CT scan of the affected areas, then overlay the CT image with the MRI image I had previously. This will give her a very full picture of what's inside so that she can plan the radiation fields in order to maximize the radiation to the tumors and minimize the radiation to the innocent bystander tissue.

To start, the radiologist puts a special tape on me that has a single wire embedded in it. She molds the wire to follow the outline of my surgery scars; that way, the scars will show up on the CT image giving her a clear picture of where the tumor beds were before being removed.

I told the surgeon to go ahead and install zippers just in case.

For reasons I'm still not clear about, I had to grab some cables that pulled my shoulders down before the molding could begin. These cables were attached what I swear looked like bungee cords and were pulled tight so that they kept kept constant tension on my hands and arms which did indeed, pull my shoulders down.

Next comes the molding of the mask to my face. The mask starts out as a flat, perforated sheet of some kind of plastic that becomes malleable and clear when soaked in hot water.

I'll bet this is how the Pillsbury dough boy started.

After soaking in hot water, the hot, dripping mask is placed on my face and neck and gently smushed by the technician so that an impression is made. It's an uncomfortable and strange feeling at first; now I know what Bill Murry went through when he got slimed in Ghostbusters. It cools off shortly and stops feeling strange and then starts feeling just uncomfortable.

A new use for bubble wrap?

During the cooling part, you shouldn't move your head or your face, or else they'll have to slime you again. If you move, the mask stretches allowing your head to move which will throw off the accuracy of measurements. This proved difficult for me because I couldn't help but think about that old Sanford and Son quote “I'm calling you ugly, I could push your face in some dough and make gorilla cookies!” but I didn't start snickering or even crack a smile.

After about five minutes the plastic fully hardened and my head and neck were firmly immobilized. I couldn't nod my head, talk, grin, or even open my eyes. From here it's just a normal CT scan process except for the fact that you've got this rigid mask pressing against your face - and I mean pressing.. I can understand where the claustrophobic would feel a a wee bit stressed at this point.

The final product, shrink wrapped for your convenience.

The actual CT scan part took around 15–20 minutes, plus an extra 5 minutes or so for the computer to build the image.

After the image is generated, the radiologist looks at it and decides where to mark the mask in order to locate the radiation fields. In the days before this mask technique, if a radiologists needed to make a mark in order to aim the radiation, she would need to make a permanent mark on your skin in the form of a tattoo. Since the mask isn't going to let my head move and the mask will be bolted to the table in the same place, it's sufficient to simply mark the mask with locating marks.

Oh give me a clone, of my own flesh and bone...

This picture was  just too cool to leave out.

So now that the radiologist has a clear picture of the outside and inside of my head and neck, she'll go work planning radiation intensities and durations in order to kill any microscopic bits of Merkel Cell Carcinoma that the surgeon's knife may have missed. She says that it usually takes about a week to get things finalized and after consulting with the oncologist I should be looking at starting treatment in about 10 days.