Accuracy assessment of wireless transponder tracking in the operating room environment

  • Roeland Eppenga
  • Koert Kuhlmann
  • Theo Ruers
  • Jasper NijkampEmail author
Original Article



To evaluate the applicability of the Calypso® wireless transponder tracking system (Varian Medical Systems Inc., USA) for real-time tumor motion tracking during surgical procedures on tumors in non-rigid target areas. An accuracy assessment was performed for an extended electromagnetic field of view (FoV) of 27.5 × 27.5 × 22.5 cm (which included the standard FoV of 14 × 14 × 19 cm) in which 5DOF wireless Beacon® transponders can be tracked.


Using a custom-made measurement setup, we assessed single transponder relative accuracy, absolute accuracy and jitter throughout the extended FoV at 1440 locations interspaced with 2.5 cm in each orthogonal direction. The NDI Polaris Spectra optical tracking system (OTS) was used as a reference. Measurements were taken in a room without surrounding distorting factors and repeated in an operating room (OR). In the OR, the influence of a carbon fiber and regular stainless steel OR tabletop was investigated.


The calibration of the OTS and transponder system resulted in an average root-mean-square error (RMSE) vector of 0.03 cm. For both the standard and extended FoV, all accuracy measures were dependent on transponder to tracking array (TA) distances and the absolute accuracy was also dependent on TA to OR tabletop distances. This latter influence was reproducible, and after calibrating this, the residual error was below 0.1 cm RMSE within the entire standard FoV. Within the extended FoV, this residual RMSE did not exceed 0.1 cm for transponder to TA distances up to 25 cm.


This study shows that transponder tracking is promising for accurate tumor tracking in the operating room. This applies when using the standard FoV, but also when using the extended FoV up to 25 cm above the TA, substantially increasing flexibility.


Accuracy assessment Electromagnetic tracking Surgical navigation Wireless tracking Surgical oncology Abdominal surgery 



We would like to thank Ton Vlasveld for his help in fabricating the measurement setup and Professor Jan-Jakob Sonke for his insightful input. We would like to thank Koningin Wilhelmina Fonds - Alpe d’HuZes (NKI 2014-6596) for their funding.


This study was funded by KWF-Alpe d’HuZes (NKI 2014-6596)

Compliance with ethical standards

Conflict of interest

The Netherlands Cancer Institute that facilitated this research has a research agreement with Varian Medical Systems. Varian was not involved in the design or execution of the study.

Human and animal rights

This article does not contain any studies with human participants or animals performed by any of the authors.


  1. 1.
    Senft C, Ulrich CT, Seifert V, Gasser T (2010) Intraoperative magnetic resonance imaging in the surgical treatment of cerebral metastases. J Surg Oncol 101:436–441PubMedGoogle Scholar
  2. 2.
    Ochs BG, Schreiner AJ, de Zwart PM, Stockle U, Gonser CE (2016) Computer-assisted navigation is beneficial both in primary and revision surgery with modular rotating-hinge knee arthroplasty. Knee Surg Sports Traumatol Arthrosc 24:64–73CrossRefGoogle Scholar
  3. 3.
    Lango T, Tangen GA, Marvik R, Ystgaard B, Yavuz Y, Kaspersen JH, Solberg OV, Hernes TA (2008) Navigation in laparoscopy—prototype research platform for improved image-guided surgery. Minim Invasive Ther Allied Technol 17:17–33CrossRefGoogle Scholar
  4. 4.
    Aschendorff A, Maier W, Jaekel K, Wesarg T, Arndt S, Laszig R, Voss P, Metzger M, Schulze D (2009) Radiologically assisted navigation in cochlear implantation for X-linked deafness malformation. Cochlear Implant Int 10(Suppl 1):14–18CrossRefGoogle Scholar
  5. 5.
    Galloway RL, Herrell SD, Miga MI (2012) Image-guided abdominal surgery and therapy delivery. J Healthc Eng 3:203–228CrossRefGoogle Scholar
  6. 6.
    Simpson AL, Kingham TP (2016) Current evidence in image-guided liver surgery. J Gastrointest Surg 20:1265–1269CrossRefGoogle Scholar
  7. 7.
    Kingham TP, Scherer MA, Neese BW, Clements LW, Stefansic JD, Jarnagin WR (2012) Image-guided liver surgery: intraoperative projection of computed tomography images utilizing tracked ultrasound. HPB 14:594–603CrossRefGoogle Scholar
  8. 8.
    Peterhans M, vom Berg A, Dagon B, Inderbitzin D, Baur C, Candinas D, Weber S (2011) A navigation system for open liver surgery: design, workflow and first clinical applications. Int J Med Robot 7:7–16CrossRefGoogle Scholar
  9. 9.
    Su LM, Vagvolgyi BP, Agarwal R, Reiley CE, Taylor RH, Hager GD (2009) Augmented reality during robot-assisted laparoscopic partial nephrectomy: toward real-time 3D-CT to stereoscopic video registration. Urology 73:896–900CrossRefGoogle Scholar
  10. 10.
    Sugimoto M, Yasuda H, Koda K, Suzuki M, Yamazaki M, Tezuka T, Kosugi C, Higuchi R, Watayo Y, Yagawa Y, Uemura S, Tsuchiya H, Azuma T (2010) Image overlay navigation by markerless surface registration in gastrointestinal, hepatobiliary and pancreatic surgery. J Hepatobiliary Pancreat Sci 17:629–636CrossRefGoogle Scholar
  11. 11.
    Soler L, Nicolau S, Pessaux P, Mutter D, Marescaux J (2014) Real-time 3D image reconstruction guidance in liver resection surgery. Hepatobiliary Surg Nutr 3:73–81PubMedPubMedCentralGoogle Scholar
  12. 12.
    Suwelack S, Rohl S, Bodenstedt S, Reichard D, Dillmann R, dos Santos T, Maier-Hein L, Wagner M, Wunscher J, Kenngott H, Muller BP, Speidel S (2014) Physics-based shape matching for intraoperative image guidance. Med Phys 41:111901CrossRefGoogle Scholar
  13. 13.
    Collins JA, Weis JA, Heiselman JS, Clements LW, Simpson AL, Jarnagin WR, Miga MI (2017) Improving registration robustness for image-guided liver surgery in a novel human-to-phantom data framework. IEEE Trans Med Imaging 36:1502–1510CrossRefGoogle Scholar
  14. 14.
    Rucker DC, Wu Y, Clements LW, Ondrake JE, Pheiffer TS, Simpson AL, Jarnagin WR, Miga MI (2014) A mechanics-based nonrigid registration method for liver surgery using sparse intraoperative data. IEEE Trans Med Imaging 33:147–158CrossRefGoogle Scholar
  15. 15.
    Wild E, Teber D, Schmid D, Simpfendorfer T, Muller M, Baranski AC, Kenngott H, Kopka K, Maier-Hein L (2016) Robust augmented reality guidance with fluorescent markers in laparoscopic surgery. Int J Comput Assist Radiol Surg 11:899–907CrossRefGoogle Scholar
  16. 16.
    Franz AM, Haidegger T, Birkfellner W, Cleary K, Peters TM, Maier-Hein L (2014) Electromagnetic tracking in medicine–a review of technology, validation, and applications. IEEE Trans Med Imaging 33:1702–1725CrossRefGoogle Scholar
  17. 17.
    Wagner M, Gondan M, Zollner C, Wunscher JJ, Nickel F, Albala L, Groch A, Suwelack S, Speidel S, Maier-Hein L, Muller-Stich BP, Kenngott HG (2016) Electromagnetic organ tracking allows for real-time compensation of tissue shift in image-guided laparoscopic rectal surgery: results of a phantom study. Surg Endosc 30:495–503CrossRefGoogle Scholar
  18. 18.
    Ungi T, Gauvin G, Lasso A, Yeo CT, Pezeshki P, Vaughan T, Carter K, Rudan J, Engel CJ, Fichtinger G (2016) Navigated breast tumor excision using electromagnetically tracked ultrasound and surgical instruments. IEEE Trans Biomed Eng 63:600–606CrossRefGoogle Scholar
  19. 19.
    Willoughby TR, Kupelian PA, Pouliot J, Shinohara K, Aubin M, Roach M 3rd, Skrumeda LL, Balter JM, Litzenberg DW, Hadley SW, Wei JT, Sandler HM (2006) Target localization and real-time tracking using the Calypso 4D localization system in patients with localized prostate cancer. Int J Radiat Oncol Biol Phys 65:528–534CrossRefGoogle Scholar
  20. 20.
    Zhu M, Bharat S, Michalski JM, Gay HA, Hou WH, Parikh PJ (2013) Adaptive radiation therapy for postprostatectomy patients using real-time electromagnetic target motion tracking during external beam radiation therapy. Int J Radiat Oncol Biol Phys 85:1038–1044CrossRefGoogle Scholar
  21. 21.
    Zhang P, Hunt M, Happersett L, Yang J, Zelefsky M, Mageras G (2013) Robust plan optimization for electromagnetic transponder guided hypo-fractionated prostate treatment using volumetric modulated arc therapy. Phys Med Biol 58:7803–7813CrossRefGoogle Scholar
  22. 22.
    Sawant A, Smith RL, Venkat RB, Santanam L, Cho B, Poulsen P, Cattell H, Newell LJ, Parikh P, Keall PJ (2009) Toward submillimeter accuracy in the management of intrafraction motion: the integration of real-time internal position monitoring and multileaf collimator target tracking. Int J Radiat Oncol Biol Phys 74:575–582CrossRefGoogle Scholar
  23. 23.
    Kupelian P, Willoughby T, Mahadevan A, Djemil T, Weinstein G, Jani S, Enke C, Solberg T, Flores N, Liu D, Beyer D, Levine L (2007) Multi-institutional clinical experience with the Calypso system in localization and continuous, real-time monitoring of the prostate gland during external radiotherapy. Int J Radiat Oncol Biol Phys 67:1088–1098CrossRefGoogle Scholar
  24. 24.
    Sonnenday CJ, Kaufman HS (2003) Use of an implantable marker for rapid intraoperative localization of nonpalpable tumors: a pilot study in a swine colorectal model. Surg Endosc 17:1927–1931CrossRefGoogle Scholar
  25. 25.
    Nakamoto M, Ukimura O, Gill IS, Mahadevan A, Miki T, Hashizume M, Sato Y (2008) Realtime organ tracking for endoscopic augmented reality visualization using miniature wireless magnetic tracker. MIAR 5128:359–366Google Scholar
  26. 26.
    Janssen N, Eppenga R, Peeters MV, van Duijnhoven F, Oldenburg H, van der Hage J, Rutgers E, Sonke JJ, Kuhlmann K, Ruers T, Nijkamp J (2018) Real-time wireless tumor tracking during breast conserving surgery. Int J Comput Assist Radiol Surg 13:531–539CrossRefGoogle Scholar
  27. 27.
    Nafis C, Jensen V, Von Jako R (2008) Method for evaluating compatibility of commercial electromagnetic (EM) microsensor tracking systems with surgical and imaging tables. Med Imaging 6918(691820):15Google Scholar
  28. 28.
    Franz AM, Schmitt D, Seitel A, Chatrasingh M, Echner G, Oelfke U, Nill S, Birkfellner W, Maier-Hein L (2014) Standardized accuracy assessment of the calypso wireless transponder tracking system. Phys Med Biol 59:6797–6810CrossRefGoogle Scholar
  29. 29.
    Wen J (2010) Electromagnetic tracking for medical imaging. All Theses and Dissertations (ETDs) Paper 469, Washington University, Saint LouisGoogle Scholar
  30. 30.
    Balter JM, Wright JN, Newell LJ, Friemel B, Dimmer S, Cheng Y, Wong J, Vertatschitsch E, Mate TP (2005) Accuracy of a wireless localization system for radiotherapy. Int J Radiat Oncol Biol Phys 61:933–937CrossRefGoogle Scholar
  31. 31.
    Elfring R, de la Fuente M, Radermacher K (2010) Assessment of optical localizer accuracy for computer aided surgery systems. Comput Aided Surg 15:1–12CrossRefGoogle Scholar
  32. 32.
    Hummel J, Figl M, Kollmann C, Bergmann H, Birkfellner W (2002) Evaluation of a miniature electromagnetic position tracker. Med Phys 29:2205–2212CrossRefGoogle Scholar
  33. 33.
    Lasso A, Heffter T, Rankin A, Pinter C, Ungi T, Fichtinger G (2014) PLUS: open-source toolkit for ultrasound-guided intervention systems. IEEE Trans Biomed Eng 61:2527–2537CrossRefGoogle Scholar
  34. 34.
    Tukey JW (1977) Exploratory data analysis. Pearson, Don MillsGoogle Scholar
  35. 35.
    Nijkamp J, Schermers B, Schmitz S, de Jonge S, Kuhlmann K, van der Heijden F, Sonke JJ, Ruers T (2016) Comparing position and orientation accuracy of different electromagnetic sensors for tracking during interventions. Int J Comput Assist Radiol Surg 11:1487–1498CrossRefGoogle Scholar
  36. 36.
    Nafis C, Jensen V, Beauregard L, Anderson P (2006) Method for estimating dynamic EM tracking accuracy of surgical navigation tools. Proc SPIE Int Soc Opt Eng 6141:152–167Google Scholar
  37. 37.
    Nijkamp J, Kuhlmann K, Sonke J-J, Ruers T (2016) Image-guided navigation surgery for pelvic malignancies using electromagnetic tracking and intra-operative imaging. Int J Comput Assist Radiol Surg 11:2CrossRefGoogle Scholar

Copyright information

© CARS 2018

Authors and Affiliations

  1. 1.Department of Surgical OncologyThe Netherlands Cancer InstituteAmsterdamThe Netherlands
  2. 2.Nanobiophysics Group, MIRA InstituteUniversity of TwenteEnschedeThe Netherlands
  3. 3.Department of SurgeryThe Netherlands Cancer InstituteAmsterdamThe Netherlands

Personalised recommendations