A simple device for prostate and rectal localization in radiation therapy

Abstract

A simple device for prostate and rectum localization in radiation therapy may be constructed as follows: first, dental wax is used to make up a shape of the rectal probe. Second, dental stone is used to make a two-piece mold by molding the dental wax probe. Third, using the mold, the rectal probe is made from a mixture of silicone and barium. The final step involves the attachment of the “plug”, which is made of aluminum. From the simulation films for the prostate setup, the location of the anterior wall of the rectum, anal sphincter, and anal verge can easily be identified, such that the appropriate regions are shielded accordingly. A CT scan with the probe in the rectum did not give too much artifacts from the barium/silicone mixture. The rectal probe with the plug is useful for localizing the prostate more accurately, compared with using the other rectal localization techniques such as barium injection or some rectal markers.