b. The exposure technique is vital to the success of the examination. Nothing
must be taken for granted. If there is the slightest doubt regarding the technique factors
(for instance, if the patient is above or below average in size), a test or control film
should be exposed and developed prior to the injection of the contrast medium. In this
connection, it is extremely important that the specialist have a sound working
knowledge of conversion factors. This might include such things as changes from non-
grid to grid technique or vice versa, or compensating for changes in SID or mAs-kVp
relationships.
3-19. ANGIOGRAPHIC EXAMINATION OF THE UPPER EXTREMITIES
a. Arteriography.
(1) Patient preparation and administration of sensitivity test. This is covered
earlier in this section (para 3-5).
(2)
Preliminary procedure.
(a) After ascertaining whether the right or the left extremity is to be
examined, the specialist will adjust the patient in the supine position on the x-ray table,
with the arm abducted and supinated.
(b) Images are captured with digital fluoroscopy with new digital
printers printing multiple images on each film. The unprinted digital image is still
available on the image archiving system.
(c) The groin is the site most frequently used for injection. The actual
site depends upon two factors--a strong presence of a pulse and the presence of any
vessel disease.
(d) The site of injection is rendered aseptic and from 1 to 2 cc of 0.5
percent procaine solution is injected into the skin and subcutaneous tissues over the
site.
(e) From 10 to 15 cc of the contrast solution is warmed to body
temperature and placed in the syringe.
(3)
(a) The specialist selects the radiographic, technique factors and
adjusts the controls of the x-ray unit. Normally, routine (nongrid) factors for the part will
suffice, but the exposure time should be as short as possible. With everything in
readiness, the specialist assumes the "Ready" position so that the exposures can be
made without delay when the examiner gives the signal.
MD0959
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