A Tough Week
I know I have been busy when I haven’t had time to write a blog entry. This week has been busy. We had our first test in the positioning class today, and it only covered the spinal anatomy. I made a 97, so I’m quite happy with my first grade of the new semester.
We had an interesting lab in our imaging class yesterday afternoon. We had to do a demonstration of the relationship between mAs and density on radiographic film. Our experiment consisted of five x-rays, all shot at 40″ SID and a kVp of 55. We used a phantom hand and a step block as subjects and shot 5 images starting at 1.2 mAs, and doubling the mAs each time up to a mAs of 22. As we expected, each consecutive radiograph got darker, but we used the densitometer to measure the actual density on one of the step block steps for consistency purposes. What we discovered is that the data points we collected created an S curve on the graph rather than a linear relationship. What this showed us is that doubling the density won’t continue to increase the ‘blackness’ of the film noticeably after you reach a certain point. In theory, it would continue to get darker, but the film’s responsiveness falls off at a certain point. The same holds true on the lower end of the mAs range, but we didn’t really have a way to demonstrate that part of it since our controller won’t let us shoot at a mAs of less than 1.0. If our controller would let us set mAs to .1, .2, and .4, we would not have seen a dramatic change in density between those images.
There is a possibility of frozen precipitation here in the foothills of the western North Carolina mountains late tonight and tomorrow, so there is a possibility that I won’t have clinical tomorrow. Our department head instructed us NOT to go to clinical if school is closed for bad weather, and to go on a delayed schedule if the school operates on a delay. This is no big deal, but I would rather go to clinical if my clinical site is up and running. In an orthopedic office, I’m not sure how busy they would be if they were open during bad weather. I expect that a lot of appointments would probably call in and reschedule. We are allowed to miss two of the 32 scheduled clinical days this semester, but I don’t want to miss any. I need those comps!! One of the other things I’m starting to notice during my clinical time is that my confidence is rising more quickly. I feel more comfortable with the patients and doing the exams than I have in the past. I guess that’s a good sign :)
I also finished my spinal series videos, and they are all online now. The RADIOGRAPHIC POSITIONING link on the right will show those if you want to take a look. They are not professionally produced, but I think they are fairly effective, and they are free :)
