Feb 12, 2011 - 2:17 pm
Observations on the first week of my 7-week, 35-session prostate-bed TomoThreapy radiation course.
Each patient must be in full-bladder, empty rectum state prior to treatment. This means half hour before (1) empty bladder, (2) drink 160oz of water. The displacement of these two organs is scanned before the start of each session. A computer screen shows how this moves both as far out of the way of the modulated beam as is possible. An empty, partially full bladder hangs like a deflated balloon over the prostate-bed target area. The further out the way minimizes collateral damage - hence side affects.
The first three sessions for me where like nightmare on elm street II. I drank too much, too early. Lying on the trestle, within the bowels of the machine, I suffered agonizing minutes of self-torture trying to stave off peeing all over the equipment. The reason for this, in part, is that the timing of when one starts treatment can vary by as much as an hour or more - depending on the time each patient takes ahead of you. This variable is greatly affected by the result of the pre-scan. For example, if the bladder is not full enough, or too full, or the rectum has an air pocket (gas bubble), the test is held up so the patient can walk around to try eliminate the condition. Of course after each walk-around the set-up and scan has to be repeated. If this goes on long enough, those waiting have to visit the bathroom, release their straining full bladders and re-drink 16oz of water to replenish. It was not until the 5th session that I was able to better judge amount and drink and time ahead of the session to avoid this agony.
The radiation time is 13 1/2 minutes. To this must be added 5 minutes for set-up (to accurately align the body with laser-lit lines that cross dead center of the prostate bed and tiny tattoo dots placed either side of your lower abdomen), 5 mins for the pre-scan, 5-15 mins for the doctor to come view the screen and okay the test, and 2-3 mins at the end before you can hop off the trestle and rush to the rest room - a total of a half hour or more, depending on how quick the doctor can get from his interviewing schedule to the pc.
The test itself is painless and not at all unpleasant. Other than the issues described above! The key is to carefully judge amount (even to visiting the restroom to 'leak' a few ounces and replenish the same amount if you feel that you're going to be delayed over and above the scheduled time).