Hostname: page-component-76fb5796d-vfjqv Total loading time: 0 Render date: 2024-04-26T19:21:49.875Z Has data issue: false hasContentIssue false
  • English
  • Français

Comparison of verification accuracy and radiation dose between megavoltage CT and kilovoltage cone-beam CT

Published online by Cambridge University Press:  12 November 2010

Vincent W.C. Wu ,
M.L. Ho ,
L.Y. Yuen ,
K.L. Li ,
N.F. Lai ,
Y.C. Tsang ,
W.Y. Lee  and
G. Chiu
Vincent W.C. Wu
Affiliation:
Department of Health Technology and Informatics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
M.L. Ho
Affiliation:
Department of Health Technology and Informatics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
L.Y. Yuen
Affiliation:
Department of Health Technology and Informatics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
K.L. Li
Affiliation:
Department of Health Technology and Informatics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
N.F. Lai
Affiliation:
Department of Health Technology and Informatics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
Y.C. Tsang
Affiliation:
Department of Health Technology and Informatics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
W.Y. Lee
Affiliation:
Department of Radiotherapy and Oncology, Hong Kong Sanatorium and Hospital, Happy Valley, Hong Kong
G. Chiu
Affiliation:
Department of Radiotherapy and Oncology, Hong Kong Sanatorium and Hospital, Happy Valley, Hong Kong
Get access Rights & Permissions [Opens in a new window]

Abstract

Purpose: This study evaluated the difference in verification performance and organ doses between megavoltage computed tomography (MVCT) and kilovoltage cone-beam computed tomography (kV CBCT).

Methods: Anthropomorphic phantoms of head-and-neck (H&N) and pelvic regions were scanned by the computed tomography–simulator. A common reference standard setup position for each phantom was determined. Markings of known deviations from the standard position in the lateral, longitudinal and yaw displacements were made on the phantoms. The verifications by kV CBCT and MVCT were conducted in the linear accelerator and helical tomotherapy treatment unit respectively. The phantoms were then shifted in steps according to the assigned different degree of positional deviations. The discrepancy between the detected data and the known data (δD) indicated the detection error of the verification system. Thermoluminescent dosimeters were used for dose measurements of kV CBCT and MVCT.

Results: δD of the lateral translations and yaw rotation in kV CBCT of the H&N region were lower than MVCT. There were no differences in the error detection along longitudinal direction between the two verification methods. For H&N, the mean doses of the various organs were significantly lower in kV CBCT except the skin. For the pelvis, MVCT delivered significantly higher mean dose to the prostate and femoral heads.

Keywords

Kilovoltage cone-beam CTmegavoltage CTverification accuracyorgan doseanthropomorphic phantom
Type
Original Article
Information
Journal of Radiotherapy in Practice , Volume 10 , Issue 1 , March 2011 , pp. 35 - 44
Copyright
Copyright © Cambridge University Press 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Mangar, SA, Huddart, RA, Parker, CC, Dearnaley, DP, Khoo, VS, Horwich, A. Technological advances in radiotherapy for the treatment of localised prostate cancer. Eur J Cancer 2005; 41: 908–921.Google Scholar
Kam, MK, Teo, PM, Chau, RM, Cheung, KY, Choi, PH, Kwan, WH, Leung, SF, Zee, B, Chan, AT. Treatment of nasopharyngeal carcinoma with intensity-modulated radiotherapy: the Hong Kong experience. Int J Radiat Oncol Biol Phys 2004; 60: 1440–1450.CrossRefGoogle ScholarPubMed
Johansson, J, Blomquist, E, Montelius, A, Isacsson, U, Glimelius, B. Potential outcomes of modalities and techniques in radiotherapy for patients with hypopharyngeal carcinoma. Radiother Oncol 2004; 72: 129–138.CrossRefGoogle ScholarPubMed
Mackie, TR, Kapatoes, J, Ruchala, K, Lu, W, Wu, C, Olivera, G, Forrest, L, Tome, W, Welsh, J, Jeraj, R, Harari, P, Reckwerdt, P, Paliwal, B, Ritter, M, Keller, H, Fowler, J, Mehta, M. Image guidance for precise conformal radiotherapy. Int J Radiat Oncol Biol Phys 2003; 56: 89–105.Google Scholar
Schubert, LK, Westerly, DC, Tomé, WA, Mehta, MP, Soisson, ET, Mackie, TR, Ritter, MA, Khuntia, D, Harari, PM, Paliwal, BR. A comprehensive assessment by tumor site of patient setup using daily MVCT imaging from more than 3,800 helical tomotherapy treatments. Int J Radiat Oncol Biol Phys 2009; 73: 1260–1269.CrossRefGoogle ScholarPubMed
Borst, GR, Sonke, JJ, Betgen, A, Remeijer, P, van Herk, M, Lebesque, JV. Kilo-voltage cone-beam computed tomography setup measurements for lung cancer patients; first clinical results and comparison with electronic portal-imaging device. Int J Radiat Oncol Biol Phys 2007; 68: 555–561.Google Scholar
Hong, TS, Welsh, JS, Ritter, MA, Harari, PM, Jaradat, H, Mackie, TR, Mehta, MP. Megavoltage computed tomography: an emerging tool for image-guided radiotherapy. Am J Clin Oncol 2007; 30: 617–623.Google Scholar
Santanam, L, Esthappan, J, Mutic, S, Klein, EE, Goddu, SM, Chaudhari, S, Wahab, S, El Naqa, IM, Low, DA, Grigsby, PW. Estimation of setup uncertainty using planar and MVCT imaging for gynecologic malignancies. Int J Radiat Oncol Biol Phys 2008; 71: 1511–1517.Google Scholar
Ezzell, GA, Galvin, JM, Low, D, Palta, JR, Rosen, I, Sharpe, MB, Xia, P, Xiao, Y, Xing, L, Yu, CX; IMRT subcommitte; AAPM Radiation Therapy committee. Guidance document on delivery, treatment planning, and clinical implementation of IMRT: report of the IMRT subcommittee of the AAPM Radiation Therapy Committee. Med Phys 2003; 30: 2089–2115.Google Scholar
Walter, C, Boda-Heggemann, J, Wertz, H, Loeb, I, Rahn, A, Lohr, F, Wenz, F. Phantom and in-vivo measurements of dose exposure by image-guided radiotherapy (IGRT): MV portal images vs. kV portal images vs. cone-beam CT. Radiother Oncol 2007; 85: 418–423.Google Scholar
Zhu, L, Starman, J, Fahrig, R. An Efficient Estimation Method for Reducing the Axial Intensity Drop in Circular Cone-Beam CT. Int J Biomed Imaging 2008; 2008:242841.CrossRefGoogle ScholarPubMed
Renström, J. Evaluation of the Elekta Synergy concept for patient positioning in image guided radiotherapy. Lund University, Lund: Medical Radiation Physics, 2005.Google Scholar
Shah, AP, Langen, KM, Ruchala, KJ, Cox, A, Kupelian, PA, Meeks, SL. Patient dose from megavoltage computed tomography imaging. Int J Radiat Oncol Biol Phys 2008; 70: 1579–1587.Google Scholar