High-dose-rate (HDR) brachytherapy uses a relatively intense source of radiation (typically 10 Curie source made of Iridium 192) delivered through temporarily-placed applicators. The source is usually attached to (or embedded in) the end of a wire or cable. The wire is driven through catheters into applicators that have previously been placed in the patient. The source dwells in a preplanned position for a preset time before stepping along the catheter. This process repeats to create the required dose distribution. By varying the position and dwell time of the radiation source, the dose is neatly sculpted to conform to the shape of the target. The patient typically receives the total dose in a series of 2-10 treatment sessions, also known as fractions.
Varian offers a computer-controlled afterloader technique comprising of the:
- Bravos™, VariSource™ iX, or GammaMedplus™ iX afterloaders
- BrachyVision™, Acuros® BV, and Vitesse™ treatment planning software
- Applicators and accessories