Meeting Banner
Abstract #2953

Accurate Real-Time Position Verification of an Ir-192 Source for Dynamic MR-Guided Single Fraction HDR Prostate Brachytherapy.

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

1Image Sciences Institute, Utrecht, Netherlands; 2Radiotherapy, University Medical Center Utrecht, Netherlands

High-dose-rate brachytherapy with Iridium-192 can dramatically improve the efficiency of cancer treatment. To ensure accurate treatment, in particular for single fraction therapy, HDR requires independent treatment verification. CT imaging allows excellent HDR-source localization, but poor organ visualization and tumour delineation. Although MRI provides excellent soft tissue contrast, its geometric accuracy is usually questioned. Therefore, often CT and MRI are combined. Accurate MRI-guidance would be extremely useful for single-fraction HDR brachy-monotherapy. Herein the feasibility of near real-time Iridium source position verification using the co-RASOR imaging technique is demonstrated. The positions on co-RASOR and CT images are shown to correspond within 1mm.

Keywords

able accurate acquisition acquisitions allow applied applying approximately around arrows bandwidth bandwidths become best block bone broad cable cancer capable causes clinical combined conn connected consists contrast control corresponds cost critical cylinder dedicated depict determined developed diameter distal disturbance dose dramatically dynamic effective ensure equipped exact excellent excitation extremely feasibility feedback field focused fraction frequency gaining generate geometrically gradient guidance guided health highly history hods homebuilt increment indicate institute intensity intra iridium larger localization localized long loss maxim measured medical merged might mono near need needed negative offset offsets often optimal optimization organ parallel paramagnetic particular peter phantom phys piece pile poor porcine position positions positive procedural projection prostate pulse radial radioactive read real reasons reception reconstructed reflected registered rigidly safe sampling scanner sciences seed sign since smaller soft source spherically spot steel steps strong subjected suite tempo therapy thick thresh tissue treatment typical useful utilizes verification view voltage wraps written