X-Tream quality assurance in synchrotron X-ray microbeam radiation therapy

Microbeam radiation therapy (MRT) is a novel irradiation technique for brain tumours treatment currently under development at the European Synchrotron Radiation Facility in Grenoble, France. The technique is based on the spatial fractionation of a highly brilliant synchrotron X-ray beam into an array of microbeams using a multi-slit collimator (MSC). After promising pre-clinical results, veterinary trials have recently commenced requiring the need for dedicated quality assurance (QA) procedures. The quality of MRT treatment demands reproducible and precise spatial fractionation of the incoming synchrotron beam. The intensity profile of the microbeams must also be quickly and quantitatively characterized prior to each treatment for comparison with that used for input to the dose-planning calculations. The Centre for Medical Radiation Physics (University of Wollongong, Australia) has developed an X-ray treatment monitoring system (X-Tream) which incorporates a high-spatial-resolution silicon strip detector (SSD) specifically designed for MRT. In-air measurements of the horizontal profile of the intrinsic microbeam X-ray field in order to determine the relative intensity of each microbeam are presented, and the alignment of the MSC is also assessed. The results show that the SSD is able to resolve individual microbeams which therefore provides invaluable QA of the horizontal field size and microbeam number and shape. They also demonstrate that the SSD used in the X-Tream system is very sensitive to any small misalignment of the MSC. In order to allow as rapid QA as possible, a fast alignment procedure of the SSD based on X-ray imaging with a low-intensity low-energy beam has been developed and is presented in this publication.

Download Full-text

Comparison of phantom materials for use in quality assurance of microbeam radiation therapy

Journal of Synchrotron Radiation ◽

10.1107/s1600577517005641 ◽

2017 ◽

Vol 24 (4) ◽

pp. 866-876 ◽

Cited By ~ 10

Author(s):

Matthew Cameron ◽

Iwan Cornelius ◽

Dean Cutajar ◽

Jeremy Davis ◽

Anatoly Rosenfeld ◽

...

Keyword(s):

Quality Assurance ◽

Radiation Therapy ◽

Treatment Plan ◽

Virtual Water ◽

Best Approximations ◽

Beam Radiation ◽

X Ray ◽

Microbeam Radiation Therapy ◽

Solid Water ◽

Low X

Microbeam radiation therapy (MRT) is a promising radiotherapy modality that uses arrays of spatially fractionated micrometre-sized beams of synchrotron radiation to irradiate tumours. Routine dosimetry quality assurance (QA) prior to treatment is necessary to identify any changes in beam condition from the treatment plan, and is undertaken using solid homogeneous phantoms. Solid phantoms are designed for, and routinely used in, megavoltage X-ray beam radiation therapy. These solid phantoms are not necessarily designed to be water-equivalent at low X-ray energies, and therefore may not be suitable for MRT QA. This work quantitatively determines the most appropriate solid phantom to use in dosimetric MRT QA. Simulated dose profiles of various phantom materials were compared with those calculated in water under the same conditions. The phantoms under consideration were RMI457 Solid Water (Gammex-RMI, Middleton, WI, USA), Plastic Water (CIRS, Norfolk, VA, USA), Plastic Water DT (CIRS, Norfolk, VA, USA), PAGAT (CIRS, Norfolk, VA, USA), RW3 Solid Phantom (PTW Freiburg, Freiburg, Germany), PMMA, Virtual Water (Med-Cal, Verona, WI, USA) and Perspex. RMI457 Solid Water and Virtual Water were found to be the best approximations for water in MRT dosimetry (within ±3% deviation in peak and 6% in valley). RW3 and Plastic Water DT approximate the relative dose distribution in water (within ±3% deviation in the peak and 5% in the valley). PAGAT, PMMA, Perspex and Plastic Water are not recommended to be used as phantoms for MRT QA, due to dosimetric discrepancies greater than 5%.

Download Full-text

Film dosimetry studies for patient specific quality assurance in microbeam radiation therapy

Physica Medica ◽

10.1016/j.ejmp.2019.09.071 ◽

2019 ◽

Vol 65 ◽

pp. 227-237

Author(s):

Alexandre Ocadiz ◽

Jayde Livingstone ◽

Mattia Donzelli ◽

Stefan Bartzsch ◽

Christian Nemoz ◽

...

Keyword(s):

Quality Assurance ◽

Radiation Therapy ◽

Patient Specific ◽

Film Dosimetry ◽

Microbeam Radiation Therapy

Download Full-text

Clinical microbeam radiation therapy with a compact source: specifications of the line-focus X-ray tube

Physics and Imaging in Radiation Oncology ◽

10.1016/j.phro.2020.05.010 ◽

2020 ◽

Vol 14 ◽

pp. 74-81

Author(s):

Johanna Winter ◽

Marek Galek ◽

Christoph Matejcek ◽

Jan J. Wilkens ◽

Kurt Aulenbacher ◽

...

Keyword(s):

Radiation Therapy ◽

X Ray ◽

Compact Source ◽

Microbeam Radiation Therapy ◽

Line Focus

Download Full-text

High resolution X-ray fluorescence imaging for a microbeam radiation therapy treatment planning system

10.1117/12.2043604 ◽

2014 ◽

Author(s):

Pavel Chtcheprov ◽

Christina Inscoe ◽

Laurel Burk ◽

Rachel Ger ◽

Hong Yuan ◽

...

Keyword(s):

Radiation Therapy ◽

High Resolution ◽

Treatment Planning ◽

Fluorescence Imaging ◽

Planning System ◽

Treatment Planning System ◽

X Ray ◽

Microbeam Radiation Therapy ◽

Radiation Therapy Treatment Planning ◽

Therapy Treatment

Download Full-text

Advanced Small Animal Conformal Radiation Therapy Device

Technology in Cancer Research & Treatment ◽

10.1177/1533034615626011 ◽

2016 ◽

Vol 16 (1) ◽

pp. 45-56 ◽

Cited By ~ 14

Author(s):

Sunil Sharma ◽

Ganesh Narayanasamy ◽

Beata Przybyla ◽

Jessica Webber ◽

Marjan Boerma ◽

...

Keyword(s):

Radiation Therapy ◽

Small Animal ◽

Therapeutic Benefit ◽

Integrated System ◽

Field Size ◽

National Council ◽

Conformal Radiation Therapy ◽

X Ray ◽

Custom Made

We have developed a small animal conformal radiation therapy device that provides a degree of geometrical/anatomical targeting comparable to what is achievable in a commercial animal irradiator. small animal conformal radiation therapy device is capable of producing precise and accurate conformal delivery of radiation to target as well as for imaging small animals. The small animal conformal radiation therapy device uses an X-ray tube, a robotic animal position system, and a digital imager. The system is in a steel enclosure with adequate lead shielding following National Council on Radiation Protection and Measurements 49 guidelines and verified with Geiger-Mueller survey meter. The X-ray source is calibrated following AAPM TG-61 specifications and mounted at 101.6 cm from the floor, which is a primary barrier. The X-ray tube is mounted on a custom-made “gantry” and has a special collimating assembly system that allows field size between 0.5 mm and 20 cm at isocenter. Three-dimensional imaging can be performed to aid target localization using the same X-ray source at custom settings and an in-house reconstruction software. The small animal conformal radiation therapy device thus provides an excellent integrated system to promote translational research in radiation oncology in an academic laboratory. The purpose of this article is to review shielding and dosimetric measurement and highlight a few successful studies that have been performed to date with our system. In addition, an example of new data from an in vivo rat model of breast cancer is presented in which spatially fractionated radiation alone and in combination with thermal ablation was applied and the therapeutic benefit examined.

Download Full-text