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LMU publication about the first experimental comparison of proton CT and dual energy X-ray CT covered by Physics World


The recently published work of the proton Computed Tomography (pCT) and dual energy CT (DECT) team (G. Dedes, J. Dickmann, K. Niepel, P. Wesp, G. Landry and K. Parodi) at our LMU Medical Physics Department and the LMU University Hospital (Departments of Radiation Oncology and Radiology), pursued in collaboration with members of the international pCT collaboration around R.W. Schulte, was selected as a research update for particle therapy by Physics World. The publication is titled “Experimental comparison of proton CT and dual energy x-ray CT for relative stopping power estimation in proton therapy” and was published in Physics in Medicine and Biology.

The publication presented results of the first experimental comparison between proton CT (pCT) and dual energy x-ray CT (DECT) in a controlled phantom study. The two imaging modalities have been proposed for accurate reconstruction of the relative to water stopping power ratio (RSP), the quantity needed for proton therapy treatment planning. Since a few years, the proton therapy scientific community raised questions about the relative performance of the two imaging techniques. The Siemens SOMATOM Definition FORCE DECT scanner and the pCT phase II preclinical prototype scanner of the Loma Linda University and the University of Santa Cruz were used in the investigation.

The result of this direct experimental study demonstrates the competitive performance of the pCT prototype compared with a state-of-the-art DECT scanner with optimal spectra separation in phantoms, and both scanners reached sub-percent mean-absolute-percent-error. The team now plans to complete the collaborative international effort on this topic with a comparison in more realistic tissue samples.