Experimental verification of stopping-power prediction from single- and dual-energy computed tomography in biological tissues. (9th January 2018)

• Record Type: Journal Article
• Authors: Möhler, Christian; Russ, Tom; Wohlfahrt, Patrick; Elter, Alina; Runz, Armin; Richter, Christian; Greilich, Steffen
• Is Part Of: Physics in medicine & biology. Volume 63:Number 2(2018:Jan.)
• Publication Date: 2018-01-09
• Subjects: proton and ion radiation therapy -- treatment planning -- stopping-power ratio -- range verification; Biophysics -- Periodicals; Medical physics -- Periodicals; 610.153
• DOI: 10.1088/1361-6560/aaa1c9
• Languages: English
• ISSNs: 0031-9155

Abstract

Abstract: An experimental setup for consecutive measurement of ion and x-ray absorption in tissue or other materials is introduced. With this setup using a 3D-printed sample container, the reference stopping-power ratio (SPR) of materials can be measured with an uncertainty of below 0.1%. A total of 65 porcine and bovine tissue samples were prepared for measurement, comprising five samples each of 13 tissue types representing about 80% of the total body mass (three different muscle and fatty tissues, liver, kidney, brain, heart, blood, lung and bone). Using a standard stoichiometric calibration for single-energy CT (SECT) as well as a state-of-the-art dual-energy CT (DECT) approach, SPR was predicted for all tissues and then compared to the measured reference. With the SECT approach, the SPRs of all tissues were predicted with a mean error of (−0.84 ± 0.12)% and a mean absolute error of (1.27 ± 0.12)%. In contrast, the DECT-based SPR predictions were overall consistent with the measured reference with a mean error of (−0.02 ± 0.15)% and a mean absolute error of (0.10 ± 0.15)%. Thus, in this study, the potential of DECT to decrease range uncertainty could be confirmed in biological tissue.