TY - JOUR
T1 - On-Board Patient Positioning for Head-and-Neck IMRT
T2 - Comparing Digital Tomosynthesis to Kilovoltage Radiography and Cone-Beam Computed Tomography
AU - Wu, Q. Jackie
AU - Godfrey, Devon J.
AU - Wang, Zhiheng
AU - Zhang, Junan
AU - Zhou, Sumin
AU - Yoo, Sua
AU - Brizel, David M.
AU - Yin, Fang Fang
N1 - Funding Information:
Supported in part by a master research grant from Varian Medical Systems.
PY - 2007/10/1
Y1 - 2007/10/1
N2 - Purpose: High-precision intensity-modulated radiotherapy demands high patient positioning accuracy. On-board digital tomosynthesis (DTS) provides three-dimensional (3D) image guidance for daily positioning with a lower imaging dose, faster acquisition, and more geometric flexibility than 3D cone-beam computed tomography (CBCT). This clinical study evaluated DTS as a daily imaging technique for patient positioning and compared the results with 3D CBCT and two-dimensional (2D) radiography. Methods and Materials: Head and neck cancer patients undergoing intensity-modulated radiotherapy were studied. For each session, the patient was positioned using laser marks. On-board imaging data sets, including 2D kilovoltage radiographs, DTS, and CBCT, were obtained to measure the daily patient positioning variations. The mean and standard deviations of the positioning variations in the translational and rotational directions were calculated. The positioning differences among 2D radiography, DTS, and CBCT were analyzed. Results: Image data sets were collected from 65 treatment fractions for 10 patients. The systematic patient positioning variation was <0.10 cm and 1.0° one dimensionally. The random variations were 0.27-0.34 cm in the translational and 0.93°-1.99° in the rotational direction. The mean vector isocenter variation was 0.48 cm. DTS with 40° and 20° scan angles in the coronal or sagittal directions yielded the same results for patient positioning. DTS performance was comparable to that of CBCT, with positioning differences of <0.1 cm and 0.5°. The positioning difference between 2D radiography and DTS was ∼0.1 cm and 0.2 cm in the vertical/longitudinal and lateral directions. Conclusion: Our results have demonstrated that DTS is a comparable 3D imaging technique to CBCT for daily patient positioning of head-and-neck patients as determined by manual registration of bony anatomy.
AB - Purpose: High-precision intensity-modulated radiotherapy demands high patient positioning accuracy. On-board digital tomosynthesis (DTS) provides three-dimensional (3D) image guidance for daily positioning with a lower imaging dose, faster acquisition, and more geometric flexibility than 3D cone-beam computed tomography (CBCT). This clinical study evaluated DTS as a daily imaging technique for patient positioning and compared the results with 3D CBCT and two-dimensional (2D) radiography. Methods and Materials: Head and neck cancer patients undergoing intensity-modulated radiotherapy were studied. For each session, the patient was positioned using laser marks. On-board imaging data sets, including 2D kilovoltage radiographs, DTS, and CBCT, were obtained to measure the daily patient positioning variations. The mean and standard deviations of the positioning variations in the translational and rotational directions were calculated. The positioning differences among 2D radiography, DTS, and CBCT were analyzed. Results: Image data sets were collected from 65 treatment fractions for 10 patients. The systematic patient positioning variation was <0.10 cm and 1.0° one dimensionally. The random variations were 0.27-0.34 cm in the translational and 0.93°-1.99° in the rotational direction. The mean vector isocenter variation was 0.48 cm. DTS with 40° and 20° scan angles in the coronal or sagittal directions yielded the same results for patient positioning. DTS performance was comparable to that of CBCT, with positioning differences of <0.1 cm and 0.5°. The positioning difference between 2D radiography and DTS was ∼0.1 cm and 0.2 cm in the vertical/longitudinal and lateral directions. Conclusion: Our results have demonstrated that DTS is a comparable 3D imaging technique to CBCT for daily patient positioning of head-and-neck patients as determined by manual registration of bony anatomy.
KW - CBCT
KW - Cone-beam computed tomography
KW - DTS
KW - Digital tomosynthesis
KW - Head and neck cancer
KW - Image-guided radiotherapy
KW - On-board imaging
KW - Setup variation
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U2 - 10.1016/j.ijrobp.2007.05.045
DO - 10.1016/j.ijrobp.2007.05.045
M3 - Article
C2 - 17869673
AN - SCOPUS:34548501324
SN - 0360-3016
VL - 69
SP - 598
EP - 606
JO - International Journal of Radiation Oncology Biology Physics
JF - International Journal of Radiation Oncology Biology Physics
IS - 2
ER -