Radioactive seed implantation involves the precise placement of small, rice-sized
radioactive seeds directly into the prostate gland under transrectal ultrasound guidance.
Two radiation isotopes are commonly used: 1) Palladium-103 (Pd-103) which has a
half-life of 17 days and emits most of the radiation over 2 months; and 2) Iodine-125 (I-
125) which has a half-life of 60 days and emits most of its radiation over 6 months.
During these time periods, the patient's prostate gland receives continuous irradiation.
When a seed implant is performed alone, without external beam radiation, it is called
monotherapy.
Procedure Preparation
Approximately two weeks prior to implantation, the patient will have routine blood tests.
He may also undergo an EKG, chest x-ray and a urinalysis. If there is any history of
heart disease or other significant medical problems such as hepatitis, diabetes or lung
disease, you should let your doctors know as soon as possible as it may be necessary to
get clearance from your internist, cardiologist or other medical specialists. Sometimes
this can take several weeks. If you have any history of a heart attack or angina, a
thallium stress test may be required.
All anti-inflammatory medications, such as aspirin, Motrin, Advil, ibuprofen, Aleve,
or naprosyn must be discontinued at least 2 weeks prior to the implant. It is OK to
take Tylenol for pain. If you are on coumadin, this must be discontinued 5-7 days
prior to the implant, under the direct supervision of the physician who prescribed
this medication. In many cases another medication is substituted for coumadin.
Prior to the implant, the patient will be instructed to take laxatives or enemas (a
bowel prep). It is very important for the rectum to be empty at the time of seed
placement. Both stool and gas will interfere with ultrasound imaging of the
prostate. If your physician has not given you these instructions, please let us know
several days before the implant.
