NARROW PHOTON-BEAM DOSIMETRY FOR LINEAR-ACCELERATOR RADIOSURGERY

The dosimetric characteristics of linear accelerator radiosurgery for 10-MV X-ray were measured. Measurement of the relative output factor a nd tissue maximum ratio with a microchamber produced results equivalen t to those of measurement with X-ray film. The 80% isodose level width measured with the microchamber was significantly smaller than that me asured with the X-ray film. For the measurement of relative output fac tor and tissue maximum ratio, a microchamber seems to be the more appr opriate choice. X-Ray film was found to be suitable for beam profile m easurement.