Monitoring external beam radiotherapy using real‐time beam visualization. Issue 1 (11th December 2014)

• Record Type: Journal Article
• Authors: Jenkins, Cesare H.; Naczynski, Dominik J.; Yu, Shu‐Jung S.; Xing, Lei
• Is Part Of: Medical physics. Volume 42:Issue 1(2015)
• Page Start: 5
• Page End: 13
• Publication Date: 2014-12-11
• Subjects: biomedical equipment -- biomedical optical imaging -- cameras -- CMOS image sensors -- collimators -- dosimetry -- gadolinium compounds -- linear accelerators -- medical image processing -- patient monitoring -- radiation therapy -- scintillation -- silicones -- terbium -- thin films; Therapeutic applications, including brachytherapy -- Optical microscopy -- Medical imaging -- X‐ray imaging -- Dosimetry/exposure assessment; Radiation therapy -- Details of cameras or camera bodies; Accessories therefor -- Cameras -- Digital computing or data processing equipment or methods, specially adapted for specific applications -- Image data processing or generation, in general -- Using diaphragms, collimators -- Imager structures -- Transforming light or analogous information into electric information -- Linear accelerators -- Scintigraphy; quality assurance -- real‐time imaging -- optical imaging -- dose delivery -- quality control; Medical imaging -- Cameras -- Dosimetry -- Image processing -- Collimators -- Linear accelerators -- Drug delivery -- Radiation treatment; Medical physics -- Periodicals; Medical physics; Geneeskunde; Natuurkunde; Toepassingen; Biophysics; Periodicals; Periodicals; Electronic journals; 610.153
• DOI: 10.1118/1.4901255
• Languages: English
• ISSNs: 0094-2405

Abstract

Abstract : Purpose: To characterize the performance of a novel radiation therapy monitoring technique that utilizes a flexible scintillating film, common optical detectors, and image processing algorithms for real‐time beam visualization (RT‐BV). Methods: Scintillating films were formed by mixing Gd2 O2 S:Tb (GOS) with silicone and casting the mixture at room temperature. The films were placed in the path of therapeutic beams generated by medical linear accelerators (LINAC). The emitted light was subsequently captured using a CMOS digital camera. Image processing algorithms were used to extract the intensity, shape, and location of the radiation field at various beam energies, dose rates, and collimator locations. The measurement results were compared with known collimator settings to validate the performance of the imaging system. Results: The RT‐BV system achieved a sufficient contrast‐to‐noise ratio to enable real‐time monitoring of the LINAC beam at 20 fps with normal ambient lighting in the LINAC room. The RT‐BV system successfully identified collimator movements with sub‐millimeter resolution. Conclusions: The RT‐BV system is capable of localizing radiation therapy beams with sub‐millimeter precision and tracking beam movement at video‐rate exposure.