Synchrotron Radiation Therapy from a Medical Physics point of view

Abstract

On the possibilities of x-ray phase contrast microimaging by coherent high-energy synchrotron radiation Review of Scientific Instruments 66, 5486 (1995) Abstract.Synchrotron radiation (SR) therapy is a promising alternative to treat brain tumors, whose management is limited due to the high morbidity of the surrounding healthy tissues. Several approaches are being explored by using SR at the European Synchrotron Radiation Facility (ESRF), where three techniques are under development: Synchrotron Stereotactic Radiation Therapy (SSRT), Microbeam Radiation Therapy (MRT) and Minibeam Radiation Therapy (MBRT).The sucess of the preclinical studies on SSRT and MRT has paved the way to clinical trials currently in preparation at the ESRF. With this aim, different dosimetric aspects from both theoretical and experimental points of view have been assessed. In particular, the definition of safe irradiation protocols, the beam energy providing the best balance between tumor treatment and healthy tissue sparing in MRT and MBRT, the special dosimetric considerations for small field dosimetry, etc will be described. In addition, for the clinical trials, the definition of appropiate dosimetry protocols for patients according to the well established European Medical Physics recommendations will be discussed. Finally, the state of the art of the MBRT technical developments at the ESRF will be presented. In 2006 A. Dilmanian and collaborators proposed the use of thicker microbeams (0.36-0.68 mm). This new type of radiotherapy is the most recently implemented technique at the ESRF and it has been called MBRT. The main advantage of MBRT with respect to MRT is that it does not require high dose rates. Therefore it can be more easily applied and extended outside synchrotron sources in the future.

Divide and conquer: spatially fractionated radiation therapy

“…This is explained by the confinement to large synchrotrons offering limited beamtime, a small scientific community, together with the high complexity of this technique both technically and dosimetrically (Ref. 63). Finally, in September 2021, the first veterinary (canine) patient was treated at the ESRF (personal communication R. Serduc).…”

Current studies and future perspectives of synchrotron radiation imaging trials in human patients

“…A family of innovative and promising techniques for radiation therapy are under development and testing at SR laboratories: the Synchrotron Stereotactic Radiation Therapy (SSRT) and the Microbeam Radiation Therapy (MRT) [59]. The SSRT is already in its clinical trail stage at the European Synchrotron Radiation Facility (ESRF) in France [60].…”

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

“…Microbeam radiation therapy (MRT) is an innovative treatment procedure which is currently in the preclinical trial phase. Arrays of microbeams having widths up to 100 µm and center-to-center spacing of 100 to 400 µm [3,4] are produced using a synchrotron x-ray source which produces a high intensity, polarized coherent beam with a spectrum of around 100 kev mean energy. The MRT dose profile is characterized by spatially alternating patterns of high dose regions (peak) separated by low dose regions (valley).…”