Respiratory motion reduction in PET/CT using abdominal compression for lung cancer patients.
OBJECTIVE
Respiratory motion causes substantial artifacts in reconstructed PET images when using helical CT as the attenuation map in PET/CT imaging. In this study, we aimed to reduce the respiratory artifacts in PET/CT images of patients with lung tumors using an abdominal compression device.


METHODS
Twelve patients with lung cancer located in the middle or lower lobe of the lung were recruited. The patients were injected with 370 MBq of 18F-FDG. During PET, the patients assumed two bed positions for 1.5 min/bed. After conducting free-breathing imaging, we obtained images of the patients with abdominal compression by applying the same setup used in the free-breathing scan. The differences in the standardized uptake value (SUV)max, SUVmean, tumor volume, and the centroid of the tumors between PET and various CT schemes were measured.


RESULTS
The SUVmax and SUVmean derived from PET/CT imaging using an abdominal compression device increased for all the lesions, compared with those obtained using the conventional approach. The percentage increases were 18.1% ±14% and 17% ±16.8% for SUVmax and SUVmean, respectively. PET/CT imaging combined with abdominal compression generally reduced the tumor mismatch between CT and the corresponding attenuation corrected PET images, with an average decrease of 1.9±1.7 mm over all the cases.


CONCLUSIONS
PET/CT imaging combined with abdominal compression reduces respiratory artifacts and PET/CT misregistration, and enhances quantitative SUV in tumor. Abdominal compression is easy to set up and is an effective method used in PET/CT imaging for clinical oncology, especially in the thoracic region.
Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung City, Taiwan; Department of Biomedical Informatics, Asia University, Taichung City, Taiwan.
Tzung-Chi
TC
Huang
Department of Radiation Oncology, China Medical University Hospital, Taichung City, Taiwan.
Yao-Ching
YC
Wang
Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung City, Taiwan.
Yu-Rou
YR
Chiou
Department of Nuclear Medicine, China Medical University Hospital, Taichung City, Taiwan.
Chia-Hung
CH
Kao
D000328:Adult; D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000295:instrumentation / Q000379:methods*; D049268:Positron-Emission Tomography / Q000295:instrumentation / Q000379:methods*; D011312:Pressure; D019275:Radiopharmaceuticals; D055425:Respiratory-Gated Imaging Techniques / Q000295:instrumentation / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18