b. In some cases, of course, it may not be desirable or possible to remove
artifacts. If you receive a trauma patient wearing a cervical collar, for example, a
necklace cannot be removed since removing it might cause further injury to the patient.
Some artifacts cannot be removed. For example, if you are doing a skull series on a
patient with a glass eye or an ear implant, the artifact cannot be removed. The same
would apply for a hip prosthesis. In such cases, you would simply have to make
accommodations, working around these potential obstacles. You will have to position
the patient so that an unobstructed view may still be obtained.
MEASURING THE PART
For each of the positions presented, step b of the order of procedure (figure 5-1,
bottom) will simply indicate measure the part. Measuring the part means measuring the
thickness of the body part in order to select the appropriate technique factors. You
must measure the thickness of the body part from the point at which the central ray will
enter up through the exit site of the CR. For a PA hand, for example, you would
measure the thickness of the patient's hand from the posterior surface to the anterior
surface through the head of the third metacarpal.
MEASUR ING THE PART
Measure the thickness of the body part from the point at which the
central ray (CR) enters, up through the exit site of the CR.
SETTING THE CONTROL PANEL
Step c of the order of procedure (figure 5-1, bottom) will simply have the entry,
set control panel. (This has been covered in Lesson 2.) Essentially, setting the control
panel means placing the correct technical factors, such as kVp and mAs on the control
panel for the part being radiographed.
SOURCE TO IMAGE RECEPTOR DISTANCE
Set the source to image receptor distance as indicated in item h of the order
of procedure (figure 5-1, bottom).
SOURCE TO IMAGE RECEPTOR DISTANCE (SID)
The SID is measured either to the tabletop or to the Bucky