TY - JOUR
T1 - Comparison of breath-hold and free-breathing positions of an external fiducial by analysis of respiratory traces
AU - Hunjan, Sandeep
AU - Starkschall, George
AU - Rosen, Isaac
AU - Prado, Karl
AU - Tolani, Naresh
AU - Balter, Peter
N1 - Funding Information:
The authors wish to acknowledge the support of the Cochrane Developmental, Psychosocial and Learning Problems (DPLP) Editorial Team, based at Queen's University Belfast and the University of Bristol, UK. We would like to thank especially Professor Geraldine Macdonald, Co-ordinating Editor; Dr Joanne Duffield, Managing Editor; Dr Sarah Davies, Deputy Managing Editor; Gemma O'Loughlin, Former Assistant Managing Editor; and Margaret Anderson, Information Specialist, for their advice and assistance throughout the editorial process. Furthermore, we would like to acknowledge the support and recommendations of Dr Nuala Livingstone, Editor with DPLP and the Cochrane Editorial and Methods Department; members of the Cochrane Editorial Unit; and the following peer reviewers for their time and comments: Professor Kate M Bennett, Department of Psychology, University of Liverpool; Dr Srini Chary, University of Calgary; Dr Martha H?fler, Mercator Institute, University of Cologne, and ResilienzExpertise, Bonn; and Dr Dimitris Mavridis, University of Ioannina. We highly appreciate the contributions of Johanna Greesz, Svenja Kamp, Svenja Frenzel, Anastasia Dor?, Paul Ludolph, Bruno Richter, Sophie Walter, Manpreet Blessin, Alice Zobel, Charlotte B?hme and Marlene Stoll to the completion of this review. We thank Steffen Reinecke and Donya A Gilan for their kind assistance with the translations of some of the included studies. We thank the Ministry of Science (MWWK) of the State Rhineland-Palatinate, Germany, for providing the funding for this review.
PY - 2008
Y1 - 2008
N2 - An internal target volume (ITV) accounting for respiratory-induced tumor motion is best obtained using 4DCT. However, when 4DCT is not available, inspiratory/expiratory breath-hold (BHinsp, BHexp) CT images have been suggested as an alternative. In such cases, an external fiducial on the abdomen can be used as a substitute for tumor motion and CT images are acquired when the marker position matches - as judged by the therapist/physicist - its positions at previously determined free-breathing (FB) respiratory extrema (FBinsp, FBexp). In this study we retrospectively determined the accuracy of these matches. Free breathing 4DCT images were acquired, followed by BHinsp and BHexp CT images for 25 patients with non-small-cell lung cancer. Respiration was monitored using a commercial external fiducial system, which generates positional information while CT studies are conducted. Software was written for statistically analyzing the displacement of the external fiducial during BHinsp and BHexp CT acquisition and comparing these displacements with corresponding mean FB extrema positions (FBinsp and FBexp, respectively) using a Student's t-test. In 72% of patients, mean positions at BHinsp differed significantly from mean positions at FBinsp (p < 0.05: 0.13 - 1.40 cm). In 92% of patients, mean positions at BHexp differed significantly from mean positions at FBexp (p < 0.05: 0.03 - 0.70 cm), although this difference was smaller than 0.5 cm in many cases (median = 0.34 cm). Our findings indicate that relying solely on abdominal external markers for accurate BH CT imaging in order to accurately estimate FB extrema positions may be subject to significant error.
AB - An internal target volume (ITV) accounting for respiratory-induced tumor motion is best obtained using 4DCT. However, when 4DCT is not available, inspiratory/expiratory breath-hold (BHinsp, BHexp) CT images have been suggested as an alternative. In such cases, an external fiducial on the abdomen can be used as a substitute for tumor motion and CT images are acquired when the marker position matches - as judged by the therapist/physicist - its positions at previously determined free-breathing (FB) respiratory extrema (FBinsp, FBexp). In this study we retrospectively determined the accuracy of these matches. Free breathing 4DCT images were acquired, followed by BHinsp and BHexp CT images for 25 patients with non-small-cell lung cancer. Respiration was monitored using a commercial external fiducial system, which generates positional information while CT studies are conducted. Software was written for statistically analyzing the displacement of the external fiducial during BHinsp and BHexp CT acquisition and comparing these displacements with corresponding mean FB extrema positions (FBinsp and FBexp, respectively) using a Student's t-test. In 72% of patients, mean positions at BHinsp differed significantly from mean positions at FBinsp (p < 0.05: 0.13 - 1.40 cm). In 92% of patients, mean positions at BHexp differed significantly from mean positions at FBexp (p < 0.05: 0.03 - 0.70 cm), although this difference was smaller than 0.5 cm in many cases (median = 0.34 cm). Our findings indicate that relying solely on abdominal external markers for accurate BH CT imaging in order to accurately estimate FB extrema positions may be subject to significant error.
KW - Breath-hold
KW - ITV
KW - Lung tumor
KW - Respiratory monitoring
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U2 - 10.1120/jacmp.v9i3.2768
DO - 10.1120/jacmp.v9i3.2768
M3 - Article
C2 - 18716589
AN - SCOPUS:57049144760
SN - 1526-9914
VL - 9
SP - 34
EP - 42
JO - Journal of applied clinical medical physics
JF - Journal of applied clinical medical physics
IS - 3
ER -