A Method for Measuring the Volume of Tumors Containing Radioactive Sources

Radiation Safety Officers are frequently confronted with the difficult decision of whether a proposed scientific experiment, that requires the use of radiation, falls within the established guidelines for radiation exposure to the personnel associated with the experiment. The ICRP defines a maximal permissible as that dose, which, in the light of present knowledge, is not expected to cause detectable bodily injury to a person at any time during his/her lifetime'. Brachytherapy, or the implantation of small radioactive sources, 'seeds', into cancerous tumors, is an example of a radiation procedure used in radiation oncology clinics, that requires the attention of an Radiation Safety Officers . Because X- and γ- rays can penetrate the epidermis of the skin, personnel associated with brachytherapy procedures are at risk Personnel working with small animals in brachytherapy research programs are similarly at risk. The present preliminary study was undertaken to determine if tumor volume in mice could be remotely measured with sufficient accuracy using a photo-measurement technique, It was anticipated that a successful outcome of the project would be the reduction of radiation exposure to research personnel evaluating brachytherapy techniques that required high activity seeds. Since radiation exposure reduces as an inverse of the square of the distance, an accurate remote measuring system would be very useful