Investigating the use of image thresholding in brachytherapy catheter reconstruction

  • Diana BinnyEmail author
  • Craig M. Lancaster
  • Tanya Kairn
  • Jamie V. Trapp
  • Phil Back
  • Robyn Cheuk
  • Scott B. Crowe
Scientific Paper


This study evaluated the accuracy of image thresholding in the reconstruction of catheters in brachytherapy treatment planning systems. Six test cases including four planar catheter configurations, an interstitial prostate and an intracavitary treatment plan were made use of in this study. The four planar CT scanned catheter arrangements included; catheters placed approximately 1, 0.5 cm apart, catheters closely arranged in a plan (<0.5 cm apart) and a loop arrangement. The intracavitary plan consisted of catheters arranged inside a mould configuration. All reconstruction methods were based on tracking wire markers placed inside the plastic catheters. Each of these catheter arrangements was reconstructed using an existing window adjustment technique (manual reconstruction) in the treatment planning system followed by a CT-based automated thresholding technique available in the same planning system. A corresponding reconstructed catheter was created using a segmented catheter structure using image thresholding from another planning system within the same department. Co-ordinates from all the reconstructed catheters were compared against each other to assess the geometric shift between manual and threshold based reconstruction on each transaxial image using in-house software and the maximum variations were recorded for assessment. It was observed in general that automated thresholding technique could assist in catheter reconstruction for catheters which are greater than 0.5 cm apart. The segmented thresholding method reported smaller variations when compared to the manual reconstruction using window adjustment technique. Automated reconstruction saves time in the brachytherapy planning, however it was noted that it is not feasible for closely spaced catheters. Segmented catheter reconstruction although time consuming, did provide a better alternative in most cases.


Brachytherapy Catheter reconstruction Image thresholding Applicator Treatment planning 



The authors would like to thank all RBWH brachytherapy staff especially Robert Fitchew, Robert McDowall and Sanna Nilsson for their planning advice and support throughout the study.

Supplementary material

13246_2016_493_MOESM1_ESM.docx (85 kb)
Supplementary material 1 (DOCX 84 kb)


  1. 1.
    Chassangne D, Duthyerix A, Almond P et al (1985) ICRU report no. 38: dose & volume specification for reporting intracavitary therapy in gynecology. International Commissioning on Radiation Units & Measurements, BethesdaGoogle Scholar
  2. 2.
    Kirisits C, Siebert FA, Baltas D, De Brabandere M, Hellebust TP, Berger D, Venselaar J (2007) Accuracy of volume and DVH parameters determined with different brachytherapy treatment planning systems. Radiother Oncol 84(3):290–297. doi: 10.1016/j.radonc.2007.06.010 CrossRefPubMedGoogle Scholar
  3. 3.
    Tyagi K, Mukundan H, Mukherjee D, Semwal M, Sarin A (2012) Non isocentric film-based intracavitary brachytherapy planning in cervical cancer: a retrospective dosimetric analysis with CT planning. J Contemp Brachyther 4(3):129–134CrossRefGoogle Scholar
  4. 4.
    Wilkinson DA, Kolar MD (2013) Failure modes and effects analysis applied to high-dose-rate brachytherapy treatment planning. Brachytherapy 12(4):382–386CrossRefPubMedGoogle Scholar
  5. 5.
    Dempsey C, Smith R, Nyathi T, Ceylan A, Howard L, Patel V, Das R, Haworth A (2013) ACPSEM brachytherapy working group recommendations for quality assurance in brachytherapy. Australas Phys Eng Sci Med 36(4):387CrossRefPubMedGoogle Scholar
  6. 6.
    Robert N, Polack GG, Sethi B, Rowlands JA, Crystal E (2015) 3D localization of electrophysiology catheters from a single x-ray cone-beam projection. Med Phys 42(10):6112–6124CrossRefPubMedGoogle Scholar
  7. 7.
    Yatziv L, Chartouni M, Datta S, Sapiro G (2012) Toward multiple catheters detection in fluoroscopic image guided interventions. IEEE Trans Inf Technol Biomed 16(4):770–781CrossRefPubMedGoogle Scholar
  8. 8.
    Milletari F, Navab N, Fallavollita P (2013) Automatic detection of multiple and overlapping EP catheters in fluoroscopic sequences. In: Medical image computing and computer-assisted intervention—MICCAI. Springer, Berlin, pp 371–379Google Scholar
  9. 9.
    Esthappan J, Hoffmann KR (2000) Estimation of catheter orientations from single-plane x-ray images. In: Medical imaging. International Society for Optics and Photonics, Bellingham, pp 28–36Google Scholar
  10. 10.
    Bharat S, Kung C, Dehghan E, Ravi A, Venugopal N, Bonillas A, Stanton D, Kruecker J (2014) Electromagnetic tracking for catheter reconstruction in ultrasound-guided high-dose-rate brachytherapy of the prostate. Brachytherapy 13(6):640–650CrossRefPubMedGoogle Scholar
  11. 11.
    Hellebust TP, Kirisits C, Berger D, Pérez-Calatayud J, De Brabandere M, De Leeuw A, Dumas I, Hudej R, Lowe G, Wills R (2010) Recommendations from gynaecological (GYN) GEC-ESTRO working group: considerations and pitfalls in commissioning and applicator reconstruction in 3D image-based treatment planning of cervix cancer brachytherapy. Radiother Oncol 96(2):153–160CrossRefPubMedGoogle Scholar
  12. 12.
    Milickovic N, Baltas D, Giannouli S, Lahanas M, Zamboglou N (2001) A new algorithm for autoreconstruction of catheters in computed tomography-based brachytherapy treatment planning. IEEE Trans Biomed Eng 48(3):372–383CrossRefPubMedGoogle Scholar
  13. 13.
    Tanderup K, Hellebust TP, Lang S, Granfeldt J, Pötter R, Lindegaard JC, Kirisits C (2008) Consequences of random and systematic reconstruction uncertainties in 3D image based brachytherapy in cervical cancer. Radiother Oncol 89(2):156–163CrossRefPubMedGoogle Scholar
  14. 14.
    Kolotas C, Baltas D, Zamboglou N (1999) CT-based interstitial HDR brachytherapy. Strahlenther Onkol 175(9):419–427CrossRefPubMedGoogle Scholar
  15. 15.
    Grigsby PW, Georgiou A, Jeffrey F, Perez CA (1993) Anatomic variation of gynecologic brachytherapy prescription points. Int J Radiat Oncol Biol Phys 27(3):725–729CrossRefPubMedGoogle Scholar
  16. 16.
    Stitt J (1991) Dose specification for inoperable endometrial carcinoma: the Madison system. Brachyther J 2:32–34Google Scholar
  17. 17.
    International Electrotechnical Commission (2002) Radiotherapy equipment—co-ordinates, movements and scales. IEC report 61217. International Electrotechnical Commission (IEC), GenevaGoogle Scholar
  18. 18.
    Nucletron Oncentra MasterPlan v4.3. Physics reference manualGoogle Scholar
  19. 19.
    Nilsson S, Moutrie Z, Cheuk R, Chan P, Lancaster C, Markwell T, Dawes J, Back P (2015) A unique approach to high-dose-rate vaginal mold brachytherapy of gynecologic malignancies. Brachytherapy 14(2):267–272CrossRefPubMedGoogle Scholar

Copyright information

© Australasian College of Physical Scientists and Engineers in Medicine 2016

Authors and Affiliations

  1. 1.Department of Radiation OncologyCancer Care Services, Royal Brisbane and Women’s HospitalBrisbaneAustralia
  2. 2.Queensland University of TechnologyBrisbaneAustralia
  3. 3.Genesis Cancer Care QueenslandBrisbaneAustralia

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