TY - JOUR
T1 - Prospective observer and software-based assessment of magnetic resonance imaging quality in head and neck cancer
T2 - Should standard positioning and immobilization be required for radiation therapy applications?
AU - Ding, Yao
AU - Mohamed, Abdallah S.R.
AU - Yang, Jinzhong
AU - Colen, Rivka R.
AU - Frank, Steven J.
AU - Wang, Jihong
AU - Wassal, Eslam Y.
AU - Wang, Wenjie
AU - Kantor, Michael E.
AU - Balter, Peter A.
AU - Rosenthal, David I.
AU - Lai, Stephen Y.
AU - Hazle, John D.
AU - Fuller, Clifton D.
N1 - Publisher Copyright:
© 2015 American Society for Radiation Oncology.
PY - 2015
Y1 - 2015
N2 - Purpose: The purpose of this study was to investigate the potential of a head and neck magnetic resonance simulation and immobilization protocol on reducing motion-induced artifacts and improving positional variance for radiation therapy applications. Methods and materials: Two groups (group 1, 17 patients; group 2, 14 patients) of patients with head and neck cancer were included under a prospective, institutional review board-approved protocol and signed informed consent. A 3.0-T magnetic resonance imaging (MRI) scanner was used for anatomic and dynamic contrast-enhanced acquisitions with standard diagnostic MRI setup for group 1 and radiation therapy immobilization devices for group 2 patients. The impact of magnetic resonance simulation/immobilization was evaluated qualitatively by 2 observers in terms of motion artifacts and positional reproducibility and quantitatively using 3-dimensional deformable registration to track intrascan maximum motion displacement of voxels inside 7 manually segmented regions of interest. Results: The image quality of group 2 (29 examinations) was significantly better than that of group 1 (50 examinations) as rated by both observers in terms of motion minimization and imaging reproducibility (P <.0001). The greatest average maximum displacement was at the region of the larynx in the posterior direction for patients in group 1 (17 mm; standard deviation, 8.6 mm), whereas the smallest average maximum displacement was at the region of the posterior fossa in the superior direction for patients in group 2 (0.4 mm; standard deviation, 0.18 mm). Compared with group 1, maximum regional motion was reduced in group 2 patients in the oral cavity, floor of mouth, oropharynx, and larynx regions; however, the motion reduction reached statistical significance only in the regions of the oral cavity and floor of mouth (P <.0001). Conclusions: The image quality of head and neck MRI in terms of motion-related artifacts and positional reproducibility was greatly improved by use of radiation therapy immobilization devices. Consequently, immobilization with external and intraoral fixation in MRI examinations is required for radiation therapy application.
AB - Purpose: The purpose of this study was to investigate the potential of a head and neck magnetic resonance simulation and immobilization protocol on reducing motion-induced artifacts and improving positional variance for radiation therapy applications. Methods and materials: Two groups (group 1, 17 patients; group 2, 14 patients) of patients with head and neck cancer were included under a prospective, institutional review board-approved protocol and signed informed consent. A 3.0-T magnetic resonance imaging (MRI) scanner was used for anatomic and dynamic contrast-enhanced acquisitions with standard diagnostic MRI setup for group 1 and radiation therapy immobilization devices for group 2 patients. The impact of magnetic resonance simulation/immobilization was evaluated qualitatively by 2 observers in terms of motion artifacts and positional reproducibility and quantitatively using 3-dimensional deformable registration to track intrascan maximum motion displacement of voxels inside 7 manually segmented regions of interest. Results: The image quality of group 2 (29 examinations) was significantly better than that of group 1 (50 examinations) as rated by both observers in terms of motion minimization and imaging reproducibility (P <.0001). The greatest average maximum displacement was at the region of the larynx in the posterior direction for patients in group 1 (17 mm; standard deviation, 8.6 mm), whereas the smallest average maximum displacement was at the region of the posterior fossa in the superior direction for patients in group 2 (0.4 mm; standard deviation, 0.18 mm). Compared with group 1, maximum regional motion was reduced in group 2 patients in the oral cavity, floor of mouth, oropharynx, and larynx regions; however, the motion reduction reached statistical significance only in the regions of the oral cavity and floor of mouth (P <.0001). Conclusions: The image quality of head and neck MRI in terms of motion-related artifacts and positional reproducibility was greatly improved by use of radiation therapy immobilization devices. Consequently, immobilization with external and intraoral fixation in MRI examinations is required for radiation therapy application.
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U2 - 10.1016/j.prro.2014.11.003
DO - 10.1016/j.prro.2014.11.003
M3 - Article
C2 - 25544553
AN - SCOPUS:84937164447
SN - 1879-8500
VL - 5
SP - e299-e308
JO - Practical radiation oncology
JF - Practical radiation oncology
IS - 4
ER -