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Respiratory correlated segment reconstruction algorithm towards four-dimensional radiation therapy using carbon ion beams.

Shinichiro Mori·Masahiro Endo·Ryosuke Kohno·Hiroshi Asakura·Kazutoshi Kohno·Tomoyasu Yashiro·Shuhei Komatsu·Susumu Kandatsu·Masayuki Baba
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Abstract

PURPOSE: To enhance the precision of treatment planning for tumors which move under respiration, we developed a respiratory-correlated segment reconstruction method (RS) based on the Feldkamp--Davis--Kress algorithm (FDK) which provides high temporal resolution and a high signal-to-noise ratio. We compared full-scan (FS-FDK) and RS-FDK with regard to dose distribution in heavy ion treatment planning. MATERIALS AND METHODS: Data acquisition for RS-FDK is done using a respiratory sensing system in cine scan mode with a 256-multi-detector row CT (256-MDCT). To evaluate the accuracy of irradiation of moving tumors, dose distributions with each algorithm were compared in heavy ion treatment planning using beam parameters obtained with FS-FDK. RESULTS: Images obtained using RS-FDK did not show motion artifacts and visualized the edges of the liver and pulmonary vessels more clearly than those with FS-FDK. The iso-dose distributions for FS-FDK covered the target volume; in contrast, RS-FDK with the beam parameter of FS-FDK image provided an insufficient dose to the target and a considerable dose to normal tissues around it. CONCLUSIONS: The information provided by RS-FDK improves accuracy in the prescription of dose-to-target volume. Further, RS-FDK allows greater precision in the delivery of radiotherapy, including 4D radiation therapy.

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AgedAged, 80 and overAlgorithmsCarbon RadioisotopesHumansMalePhantoms, ImagingRadiographic Image Interpretation, Computer-AssistedRespirationTomography, X-Ray ComputedJournal Article

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Shinichiro Mori, Masahiro Endo, Ryosuke Kohno, Hiroshi Asakura, Kazutoshi Kohno, Tomoyasu Yashiro, Shuhei Komatsu, Susumu Kandatsu, Masayuki Baba. 2006-09-01. Respiratory correlated segment reconstruction algorithm towards four-dimensional radiation therapy using carbon ion beams.. https://doi.org/10.1016/j.radonc.2006.07.035

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