TY - JOUR
T1 - A computerized framework for monitoring four-dimensional dose distributions during stereotactic body radiation therapy using a portal dose image-based 2D/3D registration approach
AU - Nakamoto, Takahiro
AU - Arimura, Hidetaka
AU - Nakamura, Katsumasa
AU - Shioyama, Yoshiyuki
AU - Mizoguchi, Asumi
AU - Hirose, Taka aki
AU - Honda, Hiroshi
AU - Umezu, Yoshiyuki
AU - Nakamura, Yasuhiko
AU - Hirata, Hideki
N1 - Funding Information:
This research was partially supported by the Ministry Education, Culture, Sports Science and Technology (MEXT), via a Grant-in-Aid for Scientific Research on Innovative Areas, 24103707 , 2012–2013.
Publisher Copyright:
© 2014 Elsevier Ltd.
PY - 2015/3/1
Y1 - 2015/3/1
N2 - A computerized framework for monitoring four-dimensional (4D) dose distributions during stereotactic body radiation therapy based on a portal dose image (PDI)-based 2D/3D registration approach has been proposed in this study. Using the PDI-based registration approach, simulated 4D "treatment" CT images were derived from the deformation of 3D planning CT images so that a 2D planning PDI could be similar to a 2D dynamic clinical PDI at a breathing phase. The planning PDI was calculated by applying a dose calculation algorithm (a pencil beam convolution algorithm) to the geometry of the planning CT image and a virtual water equivalent phantom. The dynamic clinical PDIs were estimated from electronic portal imaging device (EPID) dynamic images including breathing phase data obtained during a treatment. The parameters of the affine transformation matrix were optimized based on an objective function and a gamma pass rate using a Levenberg-Marquardt (LM) algorithm. The proposed framework was applied to the EPID dynamic images of ten lung cancer patients, which included 183 frames (mean: 18.3 per patient). The 4D dose distributions during the treatment time were successfully obtained by applying the dose calculation algorithm to the simulated 4D "treatment" CT images. The mean ± standard deviation (SD) of the percentage errors between the prescribed dose and the estimated dose at an isocenter for all cases was 3.25 ± 4.43%. The maximum error for the ten cases was 14.67% (prescribed dose: 1.50. Gy, estimated dose: 1.72. Gy), and the minimum error was 0.00%. The proposed framework could be feasible for monitoring the 4D dose distribution and dose errors within a patient's body during treatment.
AB - A computerized framework for monitoring four-dimensional (4D) dose distributions during stereotactic body radiation therapy based on a portal dose image (PDI)-based 2D/3D registration approach has been proposed in this study. Using the PDI-based registration approach, simulated 4D "treatment" CT images were derived from the deformation of 3D planning CT images so that a 2D planning PDI could be similar to a 2D dynamic clinical PDI at a breathing phase. The planning PDI was calculated by applying a dose calculation algorithm (a pencil beam convolution algorithm) to the geometry of the planning CT image and a virtual water equivalent phantom. The dynamic clinical PDIs were estimated from electronic portal imaging device (EPID) dynamic images including breathing phase data obtained during a treatment. The parameters of the affine transformation matrix were optimized based on an objective function and a gamma pass rate using a Levenberg-Marquardt (LM) algorithm. The proposed framework was applied to the EPID dynamic images of ten lung cancer patients, which included 183 frames (mean: 18.3 per patient). The 4D dose distributions during the treatment time were successfully obtained by applying the dose calculation algorithm to the simulated 4D "treatment" CT images. The mean ± standard deviation (SD) of the percentage errors between the prescribed dose and the estimated dose at an isocenter for all cases was 3.25 ± 4.43%. The maximum error for the ten cases was 14.67% (prescribed dose: 1.50. Gy, estimated dose: 1.72. Gy), and the minimum error was 0.00%. The proposed framework could be feasible for monitoring the 4D dose distribution and dose errors within a patient's body during treatment.
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U2 - 10.1016/j.compmedimag.2014.12.003
DO - 10.1016/j.compmedimag.2014.12.003
M3 - Article
C2 - 25592290
AN - SCOPUS:84923088438
SN - 0895-6111
VL - 40
SP - 1
EP - 12
JO - Computerized Medical Imaging and Graphics
JF - Computerized Medical Imaging and Graphics
ER -
