Contrast Media (Diagnostic Agents)

1. Contrast media is used in Radiography in order to visualize anatomy normally not seen.

2. It requires the administration of media into the patient.

3. Technologists must pay close attention to indications and contraindications of contrast media.

4. The use of contrast media warrants serious attention to patient reactions.

5. Human tissues inherently have low subject contrast with each other.

6. Contrast Media is generally classified as negative or positive contrast agents.

7. Contrast media are used to increase the atomic number of tissues in order to visualize them through increased subject contrast.

8. Contrast materials are an indispensable part of medical imaging.

9. Classified as positive or negative.

 

 

The Perfect Contrast Material is:

A. Very–high-contrast visualization

B. Extremely low toxicity to patient

C. Persistence in patient anatomy until imaging is completed

D. Low cost

E. Minimal or no side effects

F. No residual effects within patient

 

Key Contrast Characteristics:

A. Ability of agent to mix with body fluids

B. Viscosity

C. Ionic strength

D. Persistence in the body

E. Iodine content

F. Osmolality

G. Potential for toxicity

 

Modern contrast media are water-soluble organic iodide compounds.

A. The ideal contrast medium has high viscosity, is of sufficient radiopacity, is biologically acceptable and biologically tolerable

B. Trade names for contrast media are created by the manufacturer and usually have suffixes or prefixes that correspond to the anatomical area in which they may be employed (Cardiografin)

C.  Generic nomenclature is derived from the anion and cation of which they are composed (e.g., diatrizoate sodium)

          1.     although the preferred order (anion:cation) they may be transposed (sodium diatrizoate)

 

Popular Contrast Choices May Include:

A. Barium sulfate

B. Air/gas (CO2)

C. Oil-based iodine contrast agents

D. Water-soluble iodine contrast agents

 

Contrast Media Choices Are:

A. Barium

–Atomic no. 56

B. Iodine

–Atomic no. 53

C. Air or Gas

–Atomic no. 8