Improved determination of the position and activity of a radioactive point source inside a bulky medium using several detectors. The special case of a lung counter--a general view.

A method is described to locate a radioactive point source in a lung using a commercial array of lung detectors. The method takes advantage of the fact that modern commercial systems consist of several Ge detectors, each connected to a multi-channel analyzer, and the information from each detector can be analyzed separately. The system is calibrated with point sources placed in various locations in the lungs of a phantom.

Establishing schedules for repeated doses of strontium and for concurrent chemotherapy in hormone-resistant patients with prostate cancer: measurement of blood and urine strontium levels.

Strontium-89 (Sr-89) alone or with concurrent chemotherapy has a role in the treatment of patients with prostate cancer (PCP). The schedules for repeated doses of Sr-89 or for concurrent chemotherapy is undetermined. The objective of this study was to measure the effective half-life (Te) of Sr-89 using a detector available in a nuclear research facility.

The validity of the virtual point detector concept for absorbing media.

The concept of representing the detector volume by a virtual point detector in order to facilitate efficiency evaluations was proposed in the past for non-absorbing media. The validity of the model was expanded also to absorbing media present between the detector and a point source in front of it. Empirical values were determined based on experiments with aluminum, copper, iron and lead.