(b) The groin is the most common access site. The contrast is injected
and the first exposure is made when the examiner gives the signal. The patient should
have been instructed beforehand to remain absolutely motionless at the time the
exposure is being made.
For additional exposure, the procedure described above is
(a) When specific or localized areas of the extremity are the objects of
clinical interest (for example, a given region of the hand or forearm), pronation of the
part may be indicated. Lateral projections may also be included.
(b) Rapid-sequence exposures may be made if the necessary
apparatus is available.
(c) A collateral result of arteriography is sometimes achieved by
delaying the time of exposure so that the contrast medium enters the analogously
related venous channels on its return flow (indirect venography).
(a) Since the examiner usually works in close proximity to the field of
exposure, proper safeguards must be employed for his protection; for example, a
leaded screen positioned near the x-ray table will provide a relatively safe shelter during
the time the films are being exposed. Collimation should be used to keep the field of
irradiation within the necessary limits.
(b) A technical difficulty frequently encountered is the mistiming of the
exact instant of exposure. Perfectly coordinated teamwork is vitally important to the
success of the examination.
b. Venography. See figure 3-8.
(1) Patient preparation and administration of sensitivity test. These have
been covered earlier in this section (para 3-5).
(a) As soon as the patient is received at the x-ray clinic, the specialist
will ascertain from the examiner the site of injection and the particular portion of the
extremity to be examined.
(b) The patient is adjusted in the supine position on the x-ray table,
with the arm abducted and supinated.