Defining field output factors in small fields based on dose area product measurements: A feasibility study.

Background: Dose area product in water (DAP) in small fields relies on the use of detectors with a sensitive area larger than the irradiation field. This quantity has recently been used to establish primary standards down to 5 mm field size, with an uncertainty smaller than 0.7%.

End-to-end quality assurance for stereotactic radiotherapy with Fricke-Xylenol orange-Gelatin gel dosimeter and dual-wavelength cone-beam optical CT readout.

Purpose: The end-to-end (E2E) quality assurance (QA) test is a unique tool for validating the treatment chain undergone by patients in external radiotherapy. It should be conducted in three dimensions (3D) to get accurate results. This study aims to implement these tests with Fricke-Xylenol orange-Gelatin (FXG) gel dosimeter and a newly developed dual-wavelength reading method on the Vista16™ optical Computed Tomography (CT) scanner (ModusQA) for three treatment techniques in stereotactic radiotherapy, on Novalis (Varian) and CyberKnife (Accuray) linear accelerators.

Preliminary dosimetric characterization of EDBreast gel.

. EDBreast gel is an alternative Fricke gel dosimeter, read by Magnetic Resonance Imaging, in which sucrose is added to lower diffusion effects. This paper aims at determining the dosimetric characteristics of this dosimeter.

Dose area product primary standards established by graphite calorimetry at the LNE-LNHB for small radiation fields in radiotherapy.

Purpose: To present primary standards establishment in terms of Dose Area Product (DAP) for small field sizes.

Methods: A large section graphite calorimeter and two plane-parallel ionization chambers were designed and built in-house. These chambers were calibrated in a 6MV FFF beam at the maximum dose rate of 1400 UM/min for fields defined by specifically designed circular collimators of 5, 7.

Fricke-Xylenol orange-Gelatin gel characterization with dual wavelength cone-beam optical CT scanner for applications in stereotactic and dynamic radiotherapy.

Purpose: This study is about the development of a new dual wavelength reading method of Fricke-Xylenol orange-Gelatin (FXG) gel dosimeters on the Vista16™ optical Computed Tomography (CT) scanner to perform 3D dose distribution measurements in stereotactic and dynamic radiotherapy treatments.

Methods: The dosimetric characteristics of an optimized FXG gel composition and its optical CT readout have been evaluated. A dual wavelength reading method has been developed on the CT scanner at wavelengths 590 nm and 633 nm.