A Control System for the ESRF Synchrotron Radiation Therapy Clinical Trials

The bio-medical beamline of the European Synchrotron Radiation Facility (ESRF) located in Grenoble, France, has recently started the Phase I-II Stereotactic Synchrotron Radiation Therapy (SSRT) clinical trials targeting brain tumours. This very first SSRT protocol consists in a combined therapy where monochromatic Xrays are delivered to the tumour pre-loaded with high Z element. The challenges of this technique are the accurate positioning of the target tumour with respect to the beam and the precision of the dose delivery whilst fully assuring the patient safety. The positioning system used for previous angiography clinical trials has been adapted to this new modality. 3-D imaging is performed for positioning purpose to fit to the treatment planning. The control system of this experiment is described from the hardware and software point of view with emphasis on the constraints imposed by the Patient Safety System (PASS).