Dose delivered to the patient by megavoltage cone beam computed tomography imaging

被引:7
作者
Isambert, A. [1 ]
Ferreira, I. H. [1 ]
Bossi, A. [1 ]
Beaudre, A. [1 ]
Nicula, L. E. [1 ]
Lefkopoulos, D. [1 ]
机构
[1] Inst Gustave Roussy, Serv Phys Med, F-94805 Villejuif, France
来源
CANCER RADIOTHERAPIE | 2009年 / 13卷 / 05期
关键词
Cone beam megavoltage tomography; Delivered dose; Patient positioning; Radiation therapy; GUIDED RADIOTHERAPY; RADIATION-THERAPY; PORTAL IMAGES; IMRT; CT; QUALITY;
D O I
10.1016/j.canrad.2009.05.010
中图分类号
R73 [肿瘤学];
学科分类号
100214 ;
摘要
Purpose. - To study the dose delivered by a megavoltage cone beam computed tomography imaging system (MVCBCT) installed on a Oncor Impression (R) linac (Siemens (TM)). Materials and methods. - The acquisition of MVCBCT images was modelled in a treatment planning system by 67 photon beams (6 MV). A study was conducted to: compare the calculated and measured dose at the centre of a cylindrical phantom; compare the calculated and measured dose distributions in the Alderson-Rando phantom (pelvis); study the influence of MVCBCT image acquisition for the repositioning of a prostate cancer patient treated by 3D conformal radiotherapy (prescribed dose of 74 Gy), on the dose-volume histograms (DVH) for the treatment plus seven MVCBCT (protocol D1-3 and weekly), treatment plus 37 MVCBCT (one for each day of treatment). Results. - The difference between calculated and measured doses at the centre of the cylindrical phantom was less than 3%. A deviation of 7% maximum was found between the dose distribution calculated in the Rando phantom and the measured doses normalized at the beam isocentre. The dose delivered at the isocentre was equal to 3,7 cGy for a "5 MU" protocol, with a maximum dose of 6 cGy. In the case of the patient considered, the acquisition of 37 MVCBCT corresponded to an additional mean dose to the PTV of 1.2 Gy for a protocol "5 MU" with a significant influence on the DVH. Conclusion. - In view of this study, it appears that the doses delivered in frequent use of MVCBCT must be taken into account by the radiation oncologist in assessing the therapeutic dose delivered to the target volume and organs at risk. (C) 2009 Societe francaise de radiotherapie oncologique (SFRO). Published by Elsevier Masson SAS. All rights reserved.
引用
收藏
页码:358 / 364
页数:7
相关论文
共 15 条
[1]   Evaluation of the effect of patient dose from cone beam computed tomography on prostate IMRT using Monte Carlo simulation [J].
Chow, James C. L. ;
Leung, Michael K. K. ;
Islam, Mohammad K. ;
Norrlinger, Bernhard D. ;
Jaffray, David A. .
MEDICAL PHYSICS, 2008, 35 (01) :52-60
[2]   Image-guided radiotherapy [J].
de Crevoisier, R. ;
Isambert, A. ;
Lisbona, A. ;
Bodez, V. ;
Marguet, M. ;
Lafay, F. ;
Remonnay, R. ;
Lagrange, J. -L. .
CANCER RADIOTHERAPIE, 2007, 11 (6-7) :296-304
[3]   Accurate patient dosimetry of kilovoltage cone-beam CT in radiation therapy [J].
Ding, George X. ;
Duggan, Dennis M. ;
Coffey, Charles W. .
MEDICAL PHYSICS, 2008, 35 (03) :1135-1144
[4]   Low dose megavoltage cone beam computed tomography with an unflattened 4 MV beam from a carbon target [J].
Faddegon, Bruce A. ;
Wu, Vincent ;
Pouliot, Jean ;
Gangadharan, Bijumon ;
Bani-Hashemi, Ali .
MEDICAL PHYSICS, 2008, 35 (12) :5777-5786
[5]   The ESTRO-QUALity assurance network (EQUAL) [J].
Ferreira, IH ;
Dutreix, A ;
Bridier, A ;
Chavaudra, J ;
Svensson, H .
RADIOTHERAPY AND ONCOLOGY, 2000, 55 (03) :273-284
[6]   Patient dose and image quality from mega-voltage cone beam computed tomography imaging [J].
Gayou, Olivier ;
Parda, David S. ;
Johnson, Mark ;
Miften, Moyed .
MEDICAL PHYSICS, 2007, 34 (02) :499-506
[7]   Quality control of megavoltage cone beam CT imaging system [J].
Isambert, A. ;
Ferreira, I. H. ;
Nicula, L. E. ;
Bonniaud, G. ;
Lefkopoulos, D. .
CANCER RADIOTHERAPIE, 2008, 12 (08) :781-787
[8]   Patient dose from kilovoltage cone beam computed tomography imaging in radiation therapy [J].
Islam, Mohammad K. ;
Purdie, Thomas G. ;
Norrlinger, Bernhard D. ;
Alasti, Hamideh ;
Moseley, Douglas J. ;
Sharpe, Michael B. ;
Siewerdsen, Jeffrey H. ;
Jaffray, David A. .
MEDICAL PHYSICS, 2006, 33 (06) :1573-1582
[9]   Radiation dose from cone beam computed tomography for image-guided radiation therapy [J].
Kan, Monica W. K. ;
Leung, Lucullus H. T. ;
Wong, Wicger ;
Lam, Nelson .
INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS, 2008, 70 (01) :272-279
[10]   X-ray volumetric imaging in image-guided radiotherapy: The new standard in on-treatment imaging [J].
McBain, CA ;
Henry, AM ;
Sykes, J ;
Amer, A ;
Marchant, T ;
Moore, CM ;
Davies, J ;
Stratford, J ;
McCarthy, C ;
Porritt, B ;
Williams, P ;
Khoo, VS ;
Price, P .
INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS, 2006, 64 (02) :625-634