The radionuclides used to meet the typical three dosimetric requirements for a temporary intravascular implant has its advantages/disadvantages. What are they for beta and gamma ray sources? Pg. 491
The beta sources have several advantages over gamma sources:
- 1.) higher specific activity.
- 2.) higher dose rate.
- 3.) longer half-life.
- 4.) greater radiation safety for the patient as well as personnel.
The major disadvantage of beta sources however is:
1.) the extremely rapid radial dose falloff within the target region.
The advantage with gamma ray (Ir-192) sources are:
1.) provides relatively more uniform target dose, governed primarily by the inverse square law falloff with distance.
The disadvantage with gamma ray (Ir-192) sources are:
- 1.) requires high activity to yield a reasonbly high dose rate (> or = to 5 Gy/min).
- 2.) due to the necessary high dose rate, shielding becomes even more important but it is expensive to implement.