Road to Radiography

Today’s lab was a lot of fun. We started out by getting checked off on our film processing requirements for the semester. Since we won’t encounter film requirements in any of our clinical sites, we aren’t going to spend a lot of time studying that technique. We will be doing it in our lab from time to time, but beyond that, digital seems to be taking over. Being in the dark room was interesting. It’s challenging to get the film out of the film bay in the dark, even though the safe light (red) is on. I think if I had been in the darkroom with that light for about 10 minutes or so, I would have been able to see a lot better. I wasn’t in there long enough for my eyes to adjust to the environment.

During the second half of lab, we did some experiments to show the effects of scatter radiation. Under normal circumstances, scatter radiation is the ONLY radiation that radiographers would be exposed to. We should never be exposed to the primary beam. When radiation is applied to a patient, one of three things will happen… 1) it will be absorbed in the body 2) it will be transmitted through the body or 3) it will be deflected by the body. The deflected x-rays create what we call scatter radiation.

We placed a dummy skull on the x-ray table for this test. We put the image receptor in the bucky under the table and another receptor vertically on the table beside the skull, but outside the collimation area on table. The object was to see how much of this film placed outside of the beam area got exposed by scatter radiation. When we collimated to the entire skull and made a picture, the film to the side was heavily exposed by the scatter radiation. On the second test, we collimated tighter to only expose a 5×5″ area of the skull. The smaller collimation area didn’t expose the film nearly as much as the larger. On the final test, we placed a piece of the rubberized lead protection on the bottom half of the film cassette beside the skull. In that result, there was no visible exposure behind the lead protection area.

This experiment was a simple demonstration of scatter radiation and why we need to protect ourselves from it. Scatter radiation has lost a lot of its energy, but the cumulative effects of it can be harmful. During the class before lab, we discussed the inverse square law, which wasn’t completely new to me. In photography that law is used in a studio environment when using studio lighting. Changing the distance between the light and the subject has an almost identical effect in photography. The intensity of the light (assuming the power doesn’t change) follows the same rules as x-ray.

Tags: 1st Semester, RAD-110 by John Setzler
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