(a) Approximately 120 cc of the contrast solution is put into the syringe.
The syringe is then connected to the automatic injection system and the necessary
adjustments of the stopcock complex are made.
(b) The examiner gives the "Ready," signal to the specialist and then
starts the injection of the contrast solution at a rate of about 10 cc per second.
The specialist makes the first exposure at the instant the examiner
gives the signal.
Subsequent exposures are made according to the instructions of
d. Portal Venography.
(1) Methods. The methods of performing portal venography vary principally
in the way the contrast medium is introduced.
(a) Operative method. The contrast medium is introduced through one
of the tributaries (for example, right gastroepiploic, superior mesenteric) of the portal
vein while exposed during abdominal laparotomy. This method is the only one that will
be described here.
(b) Occlusal method. The vena cava is momentarily occluded at a
specific level by means of a special type of balloon-catheter during the injection. The
catheter is inserted via the femoral and iliac route into the vena cava.
(c) Percutaneous transhepatic method. The injection needle is
inserted through the abdominal wall just below the xiphoid process of the sternum and
then advanced through the liver into the portal vein.
(2) Patient preparation. The specific mode of patient preparation depends
upon the method of injection and the demands of the clinical situation.
(a) This examination should be done primarily in an interventional
radiologic suite that has a digital subtraction capability. At the appointed time, the
specialist will proceed to the designated operating room with a mobile x-ray unit and
portable Bucky or gridfront cassettes. When the latter are to be used, a suitable
cassette-changing tunnel may be required. The specialist must change into attire
appropriate for operating room environment before he enters the sterile operating area.
He must inquire of the surgeon in charge regarding the most favorable location for
setting up the x-ray equipment.