Technical Note: A comparison of point set registration methods for electromagnetic tracking

Beitrag in einer Fachzeitschrift

Details zur Publikation

Autorinnen und Autoren: Götz TI, Wankerl H, Tomé AM, Meyer-Baese A, Bert C, Hensel B, Lang EW
Zeitschrift: Medical Physics
Jahr der Veröffentlichung: 2019
Band: 46
Heftnummer: 5
Seitenbereich: 2025-2030
ISSN: 0094-2405
eISSN: 1522-8541


Purpose: High dose rate brachytherapy applies intense and destructive radiation. A treatment plan defines radiation source dwell positions to avoid irradiating healthy tissue. The study discusses methods to quantify any positional changes of source locations along the various treatment sessions. Methods: Electromagnetic tracking (EMT) localizes the radiation source during the treatment sessions. But in each session the relative position of the patient relative to the filed generator is changed. Hence, the measured dwell point sets need to be registered onto each other to render them comparable. Two point set registration techniques are compared: a probabilistic method called coherent point drift (CPD) and a multidimensional scaling (MDS) technique. Results: Both enable using EMT without external registration and achieve very similar results with respect to dwell position determination of the radiation source. Still MDS achieves smaller grand average deviations (CPD-rPSR: MD = 2.55 mm, MDS-PSR: MD = 2.15 mm) between subsequent dwell position determinations, which also show less variance (CPD-rPSR: IQR = 4 mm, MDS-PSR: IQR = 3 mm). Furthermore, MDS is not based on approximations and does not need an iterative procedure to track sensor positions inside the implanted catheters. Conclusion: Although both methods achieve similar results, MDS is to be preferred over rigid CPD while nonrigid CPD is unsuitable as it does not preserve topology.

FAU-Autorinnen und Autoren / FAU-Herausgeberinnen und Herausgeber

Bert, Christoph Prof. Dr. rer. nat.
Professur für Med. Strahlenphysik
Hensel, Bernhard Prof. Dr.
Max Schaldach-Stiftungsprofessur für Biomedizinische Technik

Einrichtungen weiterer Autorinnen und Autoren

Florida State University (FSU)
IEETA - Instituto de Engenharia Electrónica e Telemática de Aveiro
Universität Regensburg


Götz, T.I., Wankerl, H., Tomé, A.M., Meyer-Baese, A., Bert, C., Hensel, B., & Lang, E.W. (2019). Technical Note: A comparison of point set registration methods for electromagnetic tracking. Medical Physics, 46(5), 2025-2030.

Götz, T. I., et al. "Technical Note: A comparison of point set registration methods for electromagnetic tracking." Medical Physics 46.5 (2019): 2025-2030.


Zuletzt aktualisiert 2019-16-07 um 09:03