Dosimetry in translation total body irradiation technique: a computer treatment planning approach and an experimental study concerning lung sparing.

Purpose: To describe and evaluate a method that uses a 3-dimensional (3D) treatment planning system (TPS) to determine the relative dose to the lung, and to study the beam filtration required for lung sparing in translation total body irradiation (TBI). Special dosimetric problems related to moving couch were also considered.

Materials And Methods: The irradiation technique employed in our hospital is that of patient translation.

The influence of the X-ray spectrum at compact bone-titanium interfaces in digital dental radiography.

Objectives: To determine the optimum X-ray spectrum in digital dental radiography once the dose around an implant and the diagnostic usefulness of the image are taken into account.

Materials And Methods: A Monte Carlo code (MCNP4B) was employed for computing the dose distribution across the bone-titanium interface. The X-ray spectra used were those met in digital dental radiography; 50-70 kVp, 2 mm Al total filtration, 5 kVp increment.

Radiation absorbed doses at compact bone-titanium interfaces in diagnostic radiography: a Monte Carlo approach.

Objectives: The aim of this study was to estimate the radiation absorbed dose at cortical tissue-implant interfaces in diagnostic radiology.

Methods: Since our interest was the radiation dose at an interface (cortical bone-implant interface), a Monte Carlo simulation was considered to be the most suitable method for studying the problem. The Monte Carlo code employed was MCNP4B.

Thermoluminescence dosimetry for quality assurance in radiation therapy.

A methodology based on thermoluminescence dosimetry was developed to check the output of teletherapy units and the given doses. It was applied in a hospital as a part of an extemal quality audit programme. Over a 7 year period the mean ratios of the output doses measured by TLDs calibrated free-in-air to the doses measured at the hospital in a 6 MV X ray and in a 60Co unit were 1.

Electron density of tissues and breast cancer radiotherapy: a quantitative CT study.

Purpose: To obtain more accurate data on the electron density of tissues to be used in the treatment planning of breast cancer patients.

Methods And Materials: Single kVp quantitative computed tomography was applied in 70 women, 20 to 77 years old, to study the electron density of the breast, the thoracic wall close and parallel to the breast, and the lung parenchyma.

Results: The electron density of the entire breast decreases with increasing age in premenopausal women and remains practically constant in postmenopausal women (8% less than that of water).