A comprehensive quality assurance protocol for electromagnetic tracking in brachytherapy

Dürrbeck C, Gomez-Sarmiento IN, Androulakis I, Sauer B, Kolkman-Deurloo IK, Bert C, Beaulieu L (2024)

Publication Type: Journal article

Publication year: 2024

Journal

Medical Physics Wiley

Book Volume: 51

Pages Range: 3184-3194

Journal Issue: 5

DOI: 10.1002/mp.17017

Abstract

Background: Electromagnetic tracking (EMT) systems have proven to be a valuable source of information regarding the location and geometry of applicators in patients undergoing brachytherapy (BT). As an important element of an enhanced and individualized pre-treatment verification, EMT can play a pivotal role in detecting treatment errors and uncertainties to increase patient safety. Purpose: The purpose of this study is two-fold: to design, develop and test a dedicated measurement protocol for the use of EMT-enabled afterloaders in BT and to collect and compare the data acquired from three different radiation oncology centers in different clinical environments. Methods: A novel quality assurance (QA) phantom composed of a scaffold with supports to fix the field generator, different BT applicators, and reference sensors (sensor verification tools) was used to assess the precision (jitter error) and accuracy (relative distance errors and target registration error) of the EMT sensor integrated into an afterloader prototype. Measurements were repeated in different environments where EMT measurements are likely to be performed, namely an electromagnetically clean laboratory, a BT suite, an operating room, and, if available, a CT suite and an MRI suite dedicated to BT. Results: The mean positional jitter was consistently under 0.1 mm across all measurement points, with a slight trend of increased jitter at greater distances from the field generator. The mean variability of sensor positioning in the tested tandem and ring gynecological applicator was also below 0.1 mm. The tracking accuracy close to the center of the measurement volume was higher than at its edges. The relative distance error at the center was 0.2-0.3 mm with maximum values reaching 1.2-1.8 mm, but up to 5.5 mm for measurement points close to the edges. In general, similar accuracy results were obtained in the clinical environments and in all investigated institutions (median distance error 0.1-0.4 mm, maximum error 1.0-2.0 mm), however, errors were found to be larger in the CT suite (median distance error up to 1.0 mm, maximum error up to 3.6 mm). Conclusion: The presented quality assessment protocol for EMT systems in BT has demonstrated that EMT offers a high-accuracy determination of the applicator/implant geometry even in clinical environments. In addition to that, it has provided valuable insights into the performance of EMT-enabled afterloaders across different radiation oncology centers.

Authors with CRIS profile

Christopher Dürrbeck Department of Radiation Oncology Birte Sauer Department of Radiation Oncology Christoph Bert Professur für Med. Strahlenphysik

Involved external institutions

Erasmus University Medical Center (MC) NL Netherlands (NL) CHU de Québec-Université Laval CA Canada (CA)

How to cite

APA:

Dürrbeck, C., Gomez-Sarmiento, I.N., Androulakis, I., Sauer, B., Kolkman-Deurloo, I.K., Bert, C., & Beaulieu, L. (2024). A comprehensive quality assurance protocol for electromagnetic tracking in brachytherapy. Medical Physics, 51(5), 3184-3194. https://doi.org/10.1002/mp.17017

MLA:

Dürrbeck, Christopher, et al. "A comprehensive quality assurance protocol for electromagnetic tracking in brachytherapy." Medical Physics 51.5 (2024): 3184-3194.

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