(2)
(a) Before starting the injection procedure, a final check is made of all
apparatus for operative readiness.
(b)
From 60 to 120 cc of the contrast solution is put into the auto-
injector syringe.
(c) The syringe is connected to the injection system and the stopcock
complex is adjusted.
(d) The examiner gives the "Ready," signal to the specialist and then
starts the injection.
(e) When all but a few cubic centimeters of the contrast medium have
been injected, the examiner will give the signal "Now," or "Shoot," and the specialist
makes the first exposure.
(f)
Subsequent exposures are made at predetermined intervals.
(g)
The patient will control his respiration according to the instructions
of the examiner.
c. Venography of the Inferior Vena Cava (Cavagram).
(1) Patient preparation and administration of sensitivity test. This has been
covered earlier in this section (para 3-5).
(2) Preliminary procedure. Digital subtraction is used to demonstrate any
inferior vena cava.
(a)
The patient is placed in the supine position on the x-ray table.
(b) Pre-injection films (14x14-inch) are sometimes made to include an
AP projection exposed with a vertical CR and a lateral projection exposed with a
horizontal CR. Grid technique is used for both. These films are processed immediately
and presented to the examiner for reading.
(c) While the projection films are being developed, the injection needle
is inserted percutaneously into the lumen of the femoral vein. A plastic tube is then
connected to the needle. Adhesive tape is used to hold the needle in place.
(d) In the absence of a simultaneous biplane exposure setup, the
examiner will signify whether the AP or the lateral is to be exposed first.
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