Open AccessComparative study of dual energy cone-beam CT using a dual-layer detector and kVp switching for material decomposition
Author(s) -
Linxi Shi,
N. Robert Bennett,
Edward G. Shapiro,
Richard E. Colbeth,
Josh StarLack,
Minghui Lu,
Adam Wang
Publication year - 2020
Publication title -
medical imaging 2020: physics of medical imaging
Language(s) - English
Resource type - Conference proceedings
SCImago Journal Rank - 0.192
H-Index - 176
pISSN - 0277-786X
DOI - 10.1117/12.2549781
Subject(s) - detector , dual layer , flat panel detector , materials science , optics , energy (signal processing) , cone beam computed tomography , dual energy , decomposition , medical imaging , layer (electronics) , computer science , biomedical engineering , physics , artificial intelligence , computed tomography , medicine , radiology , chemistry , bone mineral , osteoporosis , organic chemistry , quantum mechanics , composite material , endocrinology
Cone-beam CT (CBCT) is widely used in diagnostic imaging and image-guided procedures, leading to an increasing need for advanced CBCT techniques, such as dual energy (DE) imaging. Previous studies have shown that DE-CBCT can perform quantitative material decomposition, including quantification of contrast agents, electron density, and virtual monoenergetic images. Currently, most CBCT systems perform DE imaging using a kVp switching technique. However, the disadvantages of this method are spatial and temporal misregistration as well as total scan time increase, leading to errors in the material decomposition. DE-CBCT with a dual layer flat panel detector potentially overcomes these limitations by acquiring the dual energy images simultaneously. In this work, we investigate the DE imaging performance of a prototype dual layer detector by evaluating its material decomposition capability and comparing its performance to that of the kVp switching method. Two sets of x-ray spectra were used for kVp switching: 80/120 kVp and 80/120 kVp + 1 mm Cu filtration. Our results show the dual layer detector outperforms kVp switching at 80/120 kVp with matched dose. The performance of kVp switching was better by adding 1 mm copper filtration to the high energy images (80/120 kVp + 1 mm Cu), though the dual layer detector still provided comparable performance for material decomposition tasks. Overall, both the dual layer detector and kVp switching methods provided quantitative material decomposition images in DE-CBCT, with the dual layer detector having additional potential advantages.