Section II: ORDER OF PROCEDURE (STEPS 3 THROUGH 5)
2-8.
ORDER OF PROCEDURE, STEP 3: SELECT TABLE FACTOR
a. Table Factors in General. As the term "table factors" suggests, step 3 of the
order of procedure deals with the functioning of the X-ray table itself. Should you angle
the tube? If so, by how much? Where are the left and right letter markers for a left or
right hand, or the marker for an open or closed mouth to be located? These and other
considerations regarding the X-ray table are resolved through the use of the table
factors discussed below.
ORDER OF PROCEDURE
1. Prepare patient.
2. Adjust control panel.
3. Select table factors.
4. Position patient.
5. Take exposure.
b. Film Run Down and Letter Marker. The first table factors are the film run
down (FDR) and letter marker (LM). The FRD lets you set all factors relating to the film
itself.
TABLE FACTORS
1. Film run down and letter marker.
2. Central ray angle.
3. Source to image receptor distance (SID).
4. Conefield.
(1) Physical location of film. Earlier, you determined whether or not the
X-ray would be Bucky or non-Bucky based on body part thickness. Now you will
actually place the film in the appropriate location in the Bucky tray or on top of the X-ray
table.
(2) Size of film. You will also need to determine the size film needed for the
type of examination you are going to perform. The three basic film sizes are: 8x10
(inches), 10x12 (inches), and 14x17 (inches). Besides the basic sizes, however, there
are also a few other sizes used for special studies (5x7, 14x14, and 9 1/2 x 9 1/2).
Consider, too, whether you will get multiple exposures on the same film. Taking
multiple exposures on the same film permits you to get more than one view (see figure
2-8). This facilitates comparison and saves film.
MD0961
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