Design of quality assurance for sonographic prostate brachytherapy needle guides.
OBJECTIVE
Needles are guided to their proper anatomic locations in sonographically guided percutaneous prostate brachytherapy by a mechanical system (template). A quality assurance procedure has been designed to test this template's alignment with the needle position overlay grid displayed in the sonographic image.


METHODS
A mechanical arrangement was designed to position the needles properly with respect to the prostate probe's transducer in a liquid-filled test tank. Two liquids were tested: tap water and an ethylene glycol mixture with an acoustic velocity of 1540 m/s. Needle images with the superposed grid were analyzed for needle placement accuracy.


RESULTS
The tap water produced misregistration of the needle images. The ethylene glycol mixture yielded images of vertical and horizontal needle positions accurate to 0.3 and 1 mm, respectively. Also, the importance of selecting the lowest possible equipment echo amplitude dynamic range in these tests was shown.


CONCLUSIONS
This quality assurance test with the ethylene glycol mixture will permit accurate alignment of the brachytherapy needle position overlay grid for each separate transrectal probe used.
Goldstein
Albert
A
Department of Radiology, Wayne State University School of Medicine, Detroit, Michigan, USA.
Yudelev
Mark
M
Sharma
Renu K
RK
Arterbery
Elayne
E
D001918:Brachytherapy / Q000295:instrumentation*; D019855:Ethylene Glycol; D006801:Humans; D008297:Male; D009339:Needles; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011786:Quality Control; D014159:Transducers
D019855:Ethylene Glycol