Patient-Specific Quality Assurance Protocol for Volumetric Modulated Arc Therapy using Dose Volume Histogram.

A retrospective study was performed to explore the use of dose volume histogram (DVH) metrics in a patient-specific quality assurance protocol for volumetric modulated arc therapy (VMAT). Fourteen head and neck (HN) and ten brain patients treated with VMAT at the Launceston General Hospital were retrospectively analyzed using the new protocol to identify cases where patient dose errors exceed the established action levels that were not originally detected by either point dose and/or gamma index methods. The Sun Nuclear 3DVH software was used to estimate the dose delivered to the patient volume in terms of DVH dose errors.

An in vivo investigative protocol for HDR prostate brachytherapy using urethral and rectal thermoluminescence dosimetry.

Purpose: To develop an in vivo dosimetry based investigative action level relevant for a corrective protocol for HDR brachytherapy boost treatment.

Methods And Materials: The dose delivered to points within the urethra and rectum was measured using TLD in vivo dosimetry in 56 patients. Comparisons between the urethral and rectal measurements and TPS calculations showed differences, which are related to the relative position of the implant and TLD trains, and allowed shifts of implant position relative to the prostate to be estimated.

Dose distribution and morbidity after high dose rate brachytherapy for prostate cancer: influence of V150 and V200 parameters.

The purpose of this study is to identify factors predicting morbidity in patients undergoing high dose rate (HDR) brachytherapy boost with external beam irradiation for prostate cancer. Acute and late morbidity data were collected for 104 prostate cancer patients treated with an HDR boost together with external beam radiotherapy. Significant urinary and rectal morbidity were correlated with urethral and rectal point doses, and the proportions of the target volume receiving 100%, 150% and 200% (V200) or more of the prescribed dose.