A CT calibration method based on the polybinary tissue model for radiotherapy treatment planning.

Nobuyuki Kanematsu; Naruhiro Matsufuji; Ryosuke Kohno; Shinichi Minohara; Tatsuaki Kanai

doi:10.1088/0031-9155/48/8/307

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A CT calibration method based on the polybinary tissue model for radiotherapy treatment planning.

Nobuyuki Kanematsu·Naruhiro Matsufuji·Ryosuke Kohno·Shinichi Minohara·Tatsuaki Kanai

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Abstract

A method to establish the relationship between CT number and effective density for therapeutic radiations is proposed. We approximated body tissues to mixtures of muscle, air, fat and bone. Consequently, the relationship can be calibrated only with a CT scan of their substitutes, for which we chose water, air, ethanol and potassium phosphate solution, respectively. With simple and specific corrections for non-equivalencies of the substitutes, a calibration accuracy of 1% will be achieved. We tested the calibration method with some biological materials to verify that the proposed method would offer the accuracy, simplicity and specificity required for a standard in radiotherapy treatment planning, in particular with heavy charged particles.

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Adipose Tissue Animals Bone and Bones Calibration Computer Simulation Humans Meat Models, Biological Muscle, Skeletal Phantoms, Imaging Radiometry Radiotherapy Dosage Radiotherapy Planning, Computer-Assisted Reference Standards Comparative Study Evaluation Study Journal Article Validation Study

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Nobuyuki Kanematsu, Naruhiro Matsufuji, Ryosuke Kohno, Shinichi Minohara, Tatsuaki Kanai. 2003-04-21. A CT calibration method based on the polybinary tissue model for radiotherapy treatment planning.. https://doi.org/10.1088/0031-9155%2F48%2F8%2F307

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