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Title: Sci—Fri PM: Topics — 08: The Role and Benefits of Electromagnetic Needle-Tracking Technologies in Brachytherapy

Abstract

In modern brachytherapy, application of large doses of ionizing radiation in a limited number of fractions is frequent. Furthermore, as with any surgical procedures, brachytherapy is subject to learning curve effects. In this context, there could be advantages of integrating real-time tracking of needles/catheters to existing protocols given the recent prominent advances in tracking technologies. In this work, we review the use of an electromagnetic tracking system (EMTS) based on the second generation Aurora® Planar Field Generator (Northern Digital Inc) and custom design needles (Philips Healthcare) for brachytherapy applications. The position and orientation information is obtained from 5 degrees of freedom sensors. Basic system performance characterization is performed in well-controlled conditions to establish accuracy and reproducibility as well as potential interference from standard brachytherapy equipment. The results show that sensor locations can be tracked to within 0.04mm (la) when located within 26cm of the generator. Orientation accuracy of the needle remained within ±1° in the same region, but rose quickly at larger distances. The errors on position and orientation strongly dependent the sensor position in the characterization volume (500×500×500mm{sup 3}). The presence of an ultrasound probe was shown to have negligible effects on tracking accuracy. The use of EMTS formore » automatic catheter/applicator reconstruction was also explored. Reconstruction time was less than 10 sec/channel and tips identification was within 0.69±0.29mm of the reference values. Finally, we demonstrate that hollow needle designs with special EM adaptation also allow for real-time seed drop position estimation. In phantom experiments showed that drop positions were on average within 1.6±0.9mm of the reference position measured from μCT. Altogether, EMTS offer promising benefits in a wide range of brachytherapy applications.« less

Authors:
; ; ;  [1]; ;  [2];  [3]
  1. Département de Radio-Oncologie et Centre de Recherche du CHU de Québec, CHU de Québec, Québec (Québec), and Département de Physique, de Génie Physique et d'Optique et Centre de recherche en sur le Cancer, Université Laval, Québec (Québec) (Canada)
  2. Biomedical Systems, Philips Group Innovation, High Tech Campus 34 (HTC 34), Eindhoven (Netherlands)
  3. Integrated Clinical Solutions and Marketing, Philips Healthcare, Veenpluis 4-6, Best (Netherlands)
Publication Date:
OSTI Identifier:
22407711
Resource Type:
Journal Article
Resource Relation:
Journal Name: Medical Physics; Journal Volume: 41; Journal Issue: 8; Other Information: (c) 2014 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; 60 APPLIED LIFE SCIENCES; ACCURACY; BRACHYTHERAPY; ELECTROMAGNETIC FIELDS; MONITORING; PHANTOMS; REVIEWS; SURGERY

Citation Formats

Beaulieu, L., Racine, E., Boutaleb, S., Filion, O., Poulin, E., Hautvast, G., and Binnekamp, D.. Sci—Fri PM: Topics — 08: The Role and Benefits of Electromagnetic Needle-Tracking Technologies in Brachytherapy. United States: N. p., 2014. Web. doi:10.1118/1.4894955.
Beaulieu, L., Racine, E., Boutaleb, S., Filion, O., Poulin, E., Hautvast, G., & Binnekamp, D.. Sci—Fri PM: Topics — 08: The Role and Benefits of Electromagnetic Needle-Tracking Technologies in Brachytherapy. United States. doi:10.1118/1.4894955.
Beaulieu, L., Racine, E., Boutaleb, S., Filion, O., Poulin, E., Hautvast, G., and Binnekamp, D.. Fri . "Sci—Fri PM: Topics — 08: The Role and Benefits of Electromagnetic Needle-Tracking Technologies in Brachytherapy". United States. doi:10.1118/1.4894955.
@article{osti_22407711,
title = {Sci—Fri PM: Topics — 08: The Role and Benefits of Electromagnetic Needle-Tracking Technologies in Brachytherapy},
author = {Beaulieu, L. and Racine, E. and Boutaleb, S. and Filion, O. and Poulin, E. and Hautvast, G. and Binnekamp, D.},
abstractNote = {In modern brachytherapy, application of large doses of ionizing radiation in a limited number of fractions is frequent. Furthermore, as with any surgical procedures, brachytherapy is subject to learning curve effects. In this context, there could be advantages of integrating real-time tracking of needles/catheters to existing protocols given the recent prominent advances in tracking technologies. In this work, we review the use of an electromagnetic tracking system (EMTS) based on the second generation Aurora® Planar Field Generator (Northern Digital Inc) and custom design needles (Philips Healthcare) for brachytherapy applications. The position and orientation information is obtained from 5 degrees of freedom sensors. Basic system performance characterization is performed in well-controlled conditions to establish accuracy and reproducibility as well as potential interference from standard brachytherapy equipment. The results show that sensor locations can be tracked to within 0.04mm (la) when located within 26cm of the generator. Orientation accuracy of the needle remained within ±1° in the same region, but rose quickly at larger distances. The errors on position and orientation strongly dependent the sensor position in the characterization volume (500×500×500mm{sup 3}). The presence of an ultrasound probe was shown to have negligible effects on tracking accuracy. The use of EMTS for automatic catheter/applicator reconstruction was also explored. Reconstruction time was less than 10 sec/channel and tips identification was within 0.69±0.29mm of the reference values. Finally, we demonstrate that hollow needle designs with special EM adaptation also allow for real-time seed drop position estimation. In phantom experiments showed that drop positions were on average within 1.6±0.9mm of the reference position measured from μCT. Altogether, EMTS offer promising benefits in a wide range of brachytherapy applications.},
doi = {10.1118/1.4894955},
journal = {Medical Physics},
number = 8,
volume = 41,
place = {United States},
year = {Fri Aug 15 00:00:00 EDT 2014},
month = {Fri Aug 15 00:00:00 EDT 2014}
}
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