|
|
Treatment Planning and
Volume Study
Once you and your doctor have chosen prostate brachytherapy (radioactive
seed implant) for your treatment, planning is necessary. Arrangements will
be made for a planning session lasting 1 to 2 hours, called simulation,
to take place on the basement level of the Bodine Center for Cancer Treatment,
in the Department of Radiation Oncology.
 |
 |
Axial CT scan with template superimposed on prostate
For a larger view, Click Here |
3D view of I-125 implant
For a larger view, Click Here |
The goal of the prostate brachytherapy is to treat the entire prostate
uniformly. The reason for this is that the majority of prostate cancer is
multifocal - i.e. both lobes of the prostate. The following 2 pictures are
whole mount cross sections of prostates removed by radical prostatectomy.
The inked area represent foci of prostate cancer.
 |
 |
Cross section of the prostate
For a larger view, Click Here |
Another cross section of the prostate
For a larger view, Click Here |
The simulation lets the radiation oncologist and physicist visualize
the location of your prostate, maximize the amount of radiation that can
be delivered to the tumor and minimize the radiation exposure to the bladder
and rectum. Imaging of the prostate is the first step. This will allow a
three-dimensional reconstruction of the prostate/urethra and it's relationship
to the rectum. It will also allow a calculation of the volume of the gland.
The imaging of the prostate is performed with a CAT scan and ultrasound.
These images are then reconstructed utilizing software developed at Thomas
Jefferson University and a three-dimensional model is created. The readiation
oncologist and physicist use this model to determine the exact location
of each seed. After a careful review of the treatment plan by each member
of the team (physician and physicist), a coordinate map of the prostate
is created which desribes the location coordinates for needle and seed.
This treatment plan is used in the operating room and followed closely.
Additional seeds are available in order to make adjustments at the time
of the implant. To do this, a urinary catheter is inserted through the penis
and into the bladder. A dye is injected through the urinary catheter to
outline the bladder, making it easier to visualize on the CAT scan. The
catheters are soft, flexible plastic and are removed at the end of the simulation.
While the catheters are in place, you will have a CAT scan of your pelvic
area. Your radiation oncologist and physicist will use the CAT scan and
sophisticated computers to create a three-dimensional image of your pelvis
and pelvic organs. This allows your prostate to be seen from all angles.
Using this image, your radiation oncologist will work with the physicists
to determine the best placement of the radioactive seeds for the implant.
After the CAT scan you will a trans-rectal ultrasound volume study of the
prostate performed. This examination is performed just down the hall from
the CAT scan. You will be asked to place your feet in stirrups. Then your
feet will be elevated, in a lithotomy position. This is to simulate the
implant scenario. Next, a brief 10 - 20 minute volume study of your prostate,
using ultrasound, will be performed. That will complete the evaluation of
the prostate for the purposes of treatment planning.
 |
 |
Prostate brachtherapy treatment planning software developed at Thomas
Jefferson University
For a larger view, Click Here |
Thomas Jefferson University Prostate Brachytherapy Software
For a larger view, Click Here |
For more information, please refer to our Frequently
Asked Questions Section.
|
