background: accurate small radiation field dosimetry is essential in modern radiotherapy techniques such as stereotactic radiosurgery (srs) and intensity modulated radiotherapy (imrt). precise measurement of dosimetric parameters such as beam profile, percentage depth doses and output factor of these beams are complicated due to the electron disequilibrium and the steep dose gradients. in the p...

PURPOSE To provide a comprehensive investigation of electron beam reference dosimetry using Monte Carlo simulations of the response of 10 plane-parallel and 18 cylindrical ion chamber types. Specific emphasis is placed on the determination of the optimal shift of the chambers' effective point of measurement (EPOM) and beam quality conversion factors. METHODS The EGSnrc system is used for calc...

Ionizing radiation can be used to control insect and microbial infestation of foodstuffs, inhibit sprouting, delay ripening and reduce the dangers from food-poisoning bacteria. Irradiation produces free radicals, most of which decay rapidly, although some are more persistent. These latter radicals can be detected and characterized by electron spin resonance (ESR). In bone and other calcified ti...

Dosimetry of nonuniformly distributed 210Po,67Cu, and 123I was evaluated for a single cell, modeled as a homogeneous unity-density sphere with a radius of 7.7 mum, which is typical of a B-cell lymphoma cell. A Visual Basic program was used to calculate S factors and radial absorbed dose-rate profiles for these radionuclides, taking into account their individual radiation energy spectra. The res...

Thermoluminescence dosimeters (TLD) are widely used to verify absorbed doses delivered from radiation therapy beams. Specifically, they are used by the Radiological Physics Center for mailed dosimetry for verification of therapy machine output. The effects of the random experimental uncertainties of various factors on dose calculations from TLD signals are examined, including: fading, dose resp...

Auger electron emitting radionuclides in cancer therapy offer the opportunity to deliver a high radiation dose to the tumor cells with high radiotoxicity while minimizing toxicity to normal tissue. We have in this study identified the Auger emitter Sb119 as a potent nuclide for targeted radionuclide therapy based on theoretical dosimetry calculations at a subcellular scale. From these calculati...

Total skin electron irradiation (TSEI) is an effective option for cutaneous T-cell lymphoma (CTCL). Two conventional methods used to deliver TSEI are the Stanford multiple dual field technique and the McGill rotational technique; however, both techniques require patients to stand for 10 to 30 minutes and cannot be used in nonambulatory patients. Our group has previously described technical para...

Background and purpose: European Society for Therapeutic Radiology and Oncology (ESTRO) has set up a Quality Assurance network for radiotherapy (EQUAL) carrying out dosimetry audit. Some of the work is done in cooperation with the IAEA. The network deals with measurements performed with mailed TLD irradiated in reference and non-reference conditions, for on-axis points in photons and electrons ...