Share Email Print
cover

Proceedings Paper

Monitoring electromagnetic tracking error using redundant sensors
Author(s): Vinyas Harish; Eden Bibic; Andras Lasso; Matthew S. Holden; Thomas Vaughan; Zachary Baum; Tamas Ungi; Gabor Fichtinger
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

PURPOSE: The intraoperative measurement of tracking error is crucial to ensure the reliability of electromagnetically navigated procedures. For intraoperative use, methods need to be quick to set up, easy to interpret, and not interfere with the ongoing procedure. Our goal was to evaluate the feasibility of using redundant electromagnetic sensors to alert users to tracking error in a navigated intervention setup. METHODS: Electromagnetic sensors were fixed to a rigid frame around a region of interest and on surgical tools. A software module was designed to detect tracking error by comparing real-time measurements of the differences between inter-sensor distances and angles to baseline measurements. Once these measurements were collected, a linear support vector machine-based classifier was used to predict tracking errors from redundant sensor readings. RESULTS: Measuring the deviation in the reported inter-sensor distance and angle between the needle and cautery served as a valid indicator for electromagnetic tracking error. The highest classification accuracy, 86%, was achieved based on readings from the cautery when the two sensors on the cautery were close together. The specificity of this classifier was 93% and the sensitivity was 82%. CONCLUSION: Placing redundant electromagnetic sensors in a workspace seems to be feasible for the intraoperative detection of electromagnetic tracking error in controlled environments. Further testing should be performed to optimize the measurement error threshold used for classification in the support vector machine, and improve the sensitivity of our method before application in real procedures.

Paper Details

Date Published: 3 March 2017
PDF: 9 pages
Proc. SPIE 10135, Medical Imaging 2017: Image-Guided Procedures, Robotic Interventions, and Modeling, 101352R (3 March 2017); doi: 10.1117/12.2256004
Show Author Affiliations
Vinyas Harish, Lab. for Percutaneous Surgery, Queens Univ. (Canada)
Eden Bibic, Lab. for Percutaneous Surgery, Queens Univ. (Canada)
Andras Lasso, Lab. for Percutaneous Surgery, Queens Univ. (Canada)
Matthew S. Holden, Lab. for Percutaneous Surgery, Queens Univ. (Canada)
Thomas Vaughan, Lab. for Percutaneous Surgery, Queens Univ. (Canada)
Zachary Baum, Lab. for Percutaneous Surgery, Queens Univ. (Canada)
Tamas Ungi, Lab. for Percutaneous Surgery, Queens Univ. (Canada)
Gabor Fichtinger, Lab. for Percutaneous Surgery, Queens Univ. (Canada)


Published in SPIE Proceedings Vol. 10135:
Medical Imaging 2017: Image-Guided Procedures, Robotic Interventions, and Modeling
Robert J. Webster; Baowei Fei, Editor(s)

© SPIE. Terms of Use
Back to Top