An analysis of some dosimetric uncertainties in radiation therapy.

A phenomenological analysis of the effect of several parameters on the precision of delivered dose is presented; experimental data are used to demonstrate the effect of these parameters on the delivered dose. It is shown that some setups possess inherently better precision than others; the need for strict quality control during patient treatment is supported by the data.

Acceptance testing of medical imaging equipment: CT and MRI.

Acquisition of medical imaging equipment should be followed by verification of its ability to satisfy clinical objectives. This verification normally is fulfilled by initial acceptance testing before clinical use and by an ongoing quality-assurance program thereafter. This article describes our experience with the acceptance testing of computed tomography scanners and magnetic resonance imaging systems.

A quality-assurance program for mobile CT scanners.

This article describes our six-year experience with several mobile computed tomography scanners. Our quality-assurance program includes acceptance testing, a digital image-performance program, evaluation of scanner reliability, and consideration of human/environment factors.

Tolerance of canine anastomoses to intraoperative radiation therapy.

Radiation has been given intraoperatively to various abdominal structures in dogs, using a fixed horizontal 11 MeV electron beam at the Armed Forces Radiobiologic Research Institute. Animals were irradiated with single doses of 2000, 3000 and 4500 rad to a field which extended from the bifurcation of the aorta to the rib cage. All animals were irradiated during laparotomy under general anesthesia.

A technique for field matching in primary breast irradiation.

The intrinsic divergence of photon beams presents serious matching problems in three-field treatment of the breast and the adjoining supraclavicular area. A method is presented in which appropriate beam blocking combined with suitable isocentric rotation of the treatment couch neutralize the affects of divergence so that proper matching is achieved at all depths. The geometric principles and the set-up procedures are discussed and illustrated.