The purpose of this study is to develop and evaluate a functional multisource cone beam computed tomography (ms- CBCT) scanner to mitigate some of the main limitations of the current CBCT. The benchtop ms-CBCT utilizes a carbon nanotube (CNT) field emission source array to generate multiple narrowly collimated and rapidly scanning x-ray beams, each illuminating a section of the object and collectively covering the region of interest. A contrast phantom and a Defrise phantom were imaged by the ms-CBCT, the ms-CBCT operating in the conventional CBCT configuration, and a clinical CBCT. The results show the ms-CBCT reduces the spatial nonuniformity and root-mean-square error (RMSE) of the CT HU values by respectively 75% and 60%, essentially eliminates the cone beam artifacts, increases the effective axial coverage, and improves the CNR by 30%~50% compared to the conventional CBCT at a comparable imaging dose. The results show that the ms-CBCT can potentially provides the performance of an MDCT while maintaining the essential attributes of a CBCT including volumetric imaging, low dose, affordability, and compact design.
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