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Abstract #4322

A Dual Plane Co-RASOR Technique for Accurate and Rapid Tracking and Position Verification of an Ir-192 Source for Single Fraction HDR Brachytherapy

Hendrik de Leeuw1, Marinus A. Moerland2, Marco van Vulpen2, Peter R. Seevinck1, Chris J.G. Bakker1

1Beeld, University Medical Center, Utrecht, Netherlands; 2Radiotherapy, University Medical Center, Utrecht, Netherlands

Treatment of prostate cancer by single fraction High-Dose-Rate (HDR) brachytherapy potentially provides an improvement in prostate cancer treatment, but safe dose delivery is mandatory. Accurate localization of a HDR source requires adequate temporal and spatial resolution, which are not easily achieved by conventional MRI. In this in vitro study, we present a dual plane version of the 3D co-RASOR technique. Two orthogonal 2D center-out encoded slices allow 3D tracking of an HDR brachytherapy source in inhomogeneous tissue. The method was shown to provide a spatial accuracy comparable to CT, with an appropriate temporal resolution, 3.2 seconds, for the intended application.

Keywords

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