Radiology

2. Characteristics of Ionic Contrast
• Water soluable. Unlike barium in suspension,
iodine preparations must mix with blood.
• Stable in solution. The iodine molecule must
remain in solution. Products
• that do not meet this requirement are packages
as a solute, and solvent.

3. Characteristics of Ionic Contrast Cont…
• Low viscosity. The thickness of an agent
significantly affects the ease in which a bolus is
injected, and the rate of drip infusion.
• Low toxicity. Any preparation not natural to the
body is toxic to some degree, as are natural
substances given in excess. The goal of contrast
media is to keep adverse reactions to a minimum.
• Low osmolality. The number of particles in solution
is the chief factor of toxicity.

4. Precautions for the administration of all contrast agents
• * Check the date on the bottle, ensure correct contrast is chosen
• * Do not throw bottles away until after exam
•Contraindications:
• Glucophage – med for diabetes mellitus. When combined with
contrast increases the risk of renal failure. Recommended to be
withheld 48 hrs prior to and following contrast administration
• Multiple myeloma - Malignancy of bone that leads to renal
failure, and increases the risk of contrast reactions.

5. Contraindications Cont…
• Azotemia (uremia)- High levels of nitrogen waste in blood. Laboratory
• tests BUN (blood urea nitrogen) should be 8 – 25 mg/100 ml.
Another
• test for nitrogen waste, Creatinine levels, should be .6 to 1.5 mg/dl.
• Hypersensitivity to iodine
• Anuria – no excretion of urine
• Severe renal disease or failure
• Congestive heart disease (CHF)
• Sickle cell anemia
• Pheochromocytoma – tumor of the kidney
In certain cases, an IVU may be performed despite
contraindications
Patients should be well hydrated to lessen the risks.

6. Nonionic, low-osmolality contrast agents (LOACs)
Quickly became popular in the late 1980s
Nonionics do not disassociate into as many particles, and
therefore
create fewer ions, and less osmolality. The cost is much
greater, but comes with the promise of fewer contrast
reactions.
From Patient Care in Radiography,
5th edition. pg.269.

7. The IVU Procedure
• Because the time it takes for the kidney to excrete the
contrast is integral to the diagnosis of function, the IVU
exam is timed, and marked on every film.
• A hypertensive IVU includes films (often tomograms) done
at 1, 2, & 3 minutes, or even 30 second intervals.
• This study is done to determine if hypertension is caused
by the kidneys secreting excess renin.

8. AP PROJECTION (SCOUT AND SERIES):
INTRAVENOUS (EXCRETORY) UROGRAPHY
Pathology Demonstrated
Scout demonstrates abnormal calcifications that
may be urinary calculi. After injection, the AP
projection may demonstrate signs of obstruction,
hydronephrosis, tumor, or infection.
Intravenous (Excretory) Urography—
IVU
BASIC
• AP (scout and series)
• Nephrotomogram
• RPO and LPO (30°)
• AP - postvoid erect or recumbent

9. Rationale for the scout film
• Prior to injection a KUB (scout film) is taken to check for
technique, the position of the kidneys for the cone down
views, the success of the bowel prep, (which is similar to
that of a barium enema), and to identify calcifications that
might otherwise be obscured by the contrast.

10. NEPHROTOMOGRAM AND NEPHROGRAM: INTRAVENOUS
(EXCRETORY) UROGRAPHY
Pathology Demonstrated
Nephrogram or nephrotomogram demonstrates conditions and
trauma to the renal parenchyma. Renal cysts and/or adrenal
masses may be demonstrated during this phase of the IVU.
A nephrogram involves a
single AP radiograph of the
kidney region taken within 60
seconds following injection.