Hi Dave, I had a choline PET scan last December. As has been said by James you are taken to a room where a cannula is inserted. They then bring in the radioactive injection in a lead shield and inject the choline F18 in my case into you.
You then wait in the room for a while to let the injection over to the right places.
You are told to be careful with your urine output for a short time, any spillage will be radioactive.
I had two scans one after the other. First one of the whole body, second one a more detailed look at the pelvic area.
I found lying in the scanner with my arms up past my head for forty minutes very uncomfortable.
As Barry has said the production of choline is difficult and has a low yield.
My first scan was cancelled because the yield had been so poor it would have been useless.
They made new material the next morning and I had my scan that afternoon.
Best wishes, Ian.