Rad Exposure from Med Applications

Question 1

Name the two major users of radioactive material in a Naval MTF.

Answer 1

Diagnostic:
1. Radiography, Fluoroscopy, Mammography, CT.
2. Nuclear Medicine (PET)
Therapeutic: 
1. Radiation Oncology
2. Radiation Brachytherapy.
3. Nuclear Medicine therapy.
Blood Irradiator...

Question 2

List the ideal characteristics needed for a radiopharmaceutical.

Answer 2

1. Localizes in a specific organ (high target to non-target ratio).
2. Low Toxicity
3. Chemically stable both in-vivo and in-vitro.
4. Should emit high abundance of clinically useful photons close to 140keV
5. Should have gamma emitters with high enough energy to penetrate tissue but low enough to be attenuated by detector and not penetrate the collimator.
6. Minimal effective half-life.

Question 3

State the rationale used for selecting radioisotopes used in clinical imaging.

Answer 3

Biochemical, physiologic, and metabolic properties.

Chosen as well for minimizing patient radiation and detection characteristics of modern instrumentation.

Question 4

Name the most common radioisotope used in Nuc Med.

Answer 4

Technetium 99m.

Question 5

What is the energy and half life of Tc-99m?

Answer 5

140keV gamma rays

6 hour half-life.

Question 6

What is the general range of energy used in radiopharmaceuticals?

Answer 6

80-320keV.