Abstract: A gas scintillation detector is designed to provide in-beam absolute dose monitoring for ion beam radiotherapy treatments employing spot or raster beam scanning, especially with microsecond-scale beam pulses. Detection of prompt primary scintillation light emitted by gas molecules excited by beam passage provides electronic signals that can be processed to yield output data proportional to delivered dose up to high dose rates, and that appear quickly enough to provide feedback to influence real-time beam intensity adjustments for subsequent steps in the beam scan. When the scintillation light is collected in multiple photo-detectors, the invention is furthermore capable of measuring spot beam position with spatial resolutions of order one millimeter.

Abstract: An Active Water Phantom is designed to provide fast, accurate, high resolution, complete Quality Assurance of patient-specific treatment plans utilizing intensity-modulated Ion Beam Therapy, prior to their delivery to the patient. The detection medium is a tissue-equivalent water-based liquid scintillator material. A three-dimensional pattern of scintillation light, emitted upon ion beam irradiation, is reconstructed from three orthogonal two-dimensional light yield profiles, which are read out for each individual beam energy layer. The 3-D information has dose measurement accuracy 1-2% and spatial resolution 1-2 millimeters. The measurement sequence provides up to four orders of magnitude more data characterizing the treatment plan than currently commercially available alternatives, all in a time period no greater than that needed for actual delivery of the dose fraction to a patient.

Abstract: A method and device are designed to deliver intensity-modulated ion beam therapy radiation doses closely conforming to tumors of arbitrary shape, via a series of two-dimensional (2-D) continuous raster scans of a pencil beam, wherein each scan takes no more than about 100 milliseconds to complete. The device includes a fast scanning nozzle for the exit of an ion beam delivery gantry. The fast scanning nozzle has a fast combined-function X-Y steering magnet, and is coupled to a rastering control system capable of adjusting the length of each scan line, continuously varying the beam intensity along each scan line, and executing multiple rescans of a tumor depth layer within a single patient breathing cycle. An in-beam absolute dose and dose profile monitoring system is capable of millimeter-scale position resolution and millisecond-scale feedback to the control system to ensure the safety and efficacy of the treatment implementation.

Abstract: A gas scintillation detector is designed to provide in-beam absolute dose monitoring for ion beam radiotherapy treatments employing spot or raster beam scanning, especially with microsecond-scale beam pulses. Detection of prompt primary scintillation light emitted by gas molecules excited by beam passage provides electronic signals that can be processed to yield output data proportional to delivered dose up to high dose rates, and that appear quickly enough to provide feedback to influence real-time beam intensity adjustments for subsequent steps in the beam scan. When the scintillation light is collected in multiple photo-detectors, the invention is furthermore capable of measuring spot beam position with spatial resolutions of order one millimeter.