Brachytherapy is differentiated by the rate of irradiation dose delivered to the tumor known as high-dose rate (HDR) and low-dose rate (LDR) brachytherapy. Theoretically, there is a great difference between these two methods. Most of our knowledge is centered around LDR brachytherapy. It has been problematic to convert this knowledge to HDR brachytherapy. For this conversion, mathematical models have been developed, which still are not adequately tested for head/neck cancer. The indications for HDR brachytherapy are therefore fewer than for LDR brachytherapy.
Low-dose rate brachytherapy (LDR)
This is done by inserting radioactive rods/threads surgically into the patient. The rods remain for extended time intervals.
High-dose rate brachytherapy (HDR)
This is perfomed by moving a point-shaped radiation source through previously inserted plastic catheters (remote afterloading). The treatment is fractionated (one or two per day). Remote afterloading was introduced to reduce radiation exposure to technicians.