Feasibility study of entrance in vivo dose measurements with mailed thermoluminescence detectors.

Background And Purpose: The aim of this work is to set-up mailed entrance in vivo dosimetry by means of thermoluminescence dosimeters (TLDs) in the form of LiF powder in order to assess the overall accuracy of patient treatment delivery by comparing the doses delivered to patients with the doses calculated by the treatment planning system (TPS) in different institutions.

Patients And Methods: Two millimeter thick copper (for 6 MV photon beams) and 1.3 mm thick aluminium (for (60)Co gamma beams) build-up caps are developed.

The use of an aSi-based EPID for routine absolute dosimetric pre-treatment verification of dynamic IMRT fields.

Background And Purpose: In parallel with the increased use of intensity modulated radiation treatment (IMRT) fields in radiation therapy, flat panel amorphous silicon (aSi) detectors are becoming the standard for online portal imaging at the linear accelerator. In order to minimise the workload related to the quality assurance of the IMRT fields, we have explored the possibility of using a commercially available aSi portal imager for absolute dosimetric verification of the delivery of dynamic IMRT fields.

Patients And Methods: We investigated the basic dosimetric characteristics of an aSi portal imager (aS500, Varian Medical Systems), using an acquisition mode especially developed for portal dose (PD) integration during delivery of a-static or dynamic-radiation field.

Acceptance tests and quality control (QC) procedures for the clinical implementation of intensity modulated radiotherapy (IMRT) using inverse planning and the sliding window technique: experience from five radiotherapy departments.

Background And Purpose: An increasing number of radiotherapy centres is now aiming for clinical implementation of intensity modulated radiotherapy (IMRT), but--in contrast to conventional treatment--no national or international guidelines for commissioning of the treatment planning system (TPS) and acceptance tests of treatment equipment have yet been developed. This paper bundles the experience of five radiotherapy departments that have introduced IMRT into their clinical routine.

Methods And Materials: The five radiotherapy departments are using similar configurations since they adopted the commercially available Varian solution for IMRT, regarding treatment planning as well as treatment delivery.

A quantitative evaluation of IMRT dose distributions: refinement and clinical assessment of the gamma evaluation.

Background And Purpose: Although intensity modulated radiotherapy (IMRT) is a step forward in comparison to conventional, static beam delivery, quality assurance is more complex and labour intensive, demanding detailed two-dimensional dosimetric verification. Regardless of the technique used for measuring the dose distribution, what is essential to the implementation of routine verification of IMRT fields is the efficient and accurate comparison of the measured versus desired dose distribution. In order to achieve a fast, yet accurate quantitative measure of the correspondence between measured and calculated dose, the theoretical concept of the gamma evaluation method presented by Low et al.