(e) Other projections include the lateral rectum, sometimes done cross-
table with the patient in the prone position, during double contrast examinations.
Ensure the central ray is horizontal perpendicular. Posterior oblique projections are
also done during single contrast examinations. All projections are done according to
established procedures.
(f) After necessary radiography has been completed, the rectal tube is
withdrawn and the patient is sent to the toilet.
c. Another variation of technique is based on the use of a relatively high kVp.
Due to the greater penetration of such radiation, it is possible to visualize the
intraluminal as well as the circumjacent aspects of the colon. For example, sessile or
pedunculated growths, such as polypoid lesions, can be shown just as cholesterol
stones are demonstrated within the radiopacified bile in the gallbladder. In general, this
method is carried out as follows.
(1) Patient preparation is usually the same as for the previously described
methods, unless the radiologist prescribes otherwise.
(2) The barium sulfate suspension is prepared in the ratio of one part of
barium sulfate powder with four to six parts of water by volume, depending upon the
preferences of the radiologist and the nature of the particular case under consideration.
(3) The barium sulfate suspension is introduced into the colon by gravity.
This introduction of the medium is always done under fluoroscopic control.
(4) Spot-filming may be carried out by conventional technique or by a
relatively high-kilovoltage technique, using from 120 to 140 kVp.
(5) Radiography is done after completion of the fluoroscopic part of the
examination and before evacuation. The prescribed projections are made with the
patient postured according to the instructions of the radiologist.
(6) After completion of radiography, the patient is allowed to evacuate, and
post-evacuation radiographs are made, if required.
2-6.
LARGE INTESTINE (SINGLE CONTRAST) BARIUM ENEMA
a. Routine Views of the Barium Enema.
(1)
PA or AP.
(2)
RAO and LAO (or RPO and LPO).
MD0959
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