title: Compact CT/SPECT Small-Animal Imaging System.
abstract: We have developed a dual-modality CT/SPECT imaging system for small-animal imaging applications. The X-ray system comprises a commercially available micro-focus X-ray tube and a CCD-based X-ray camera. X-ray transmission measurements are performed based on cone-beam geometry. Individual projections are acquired by rotating the animal about a vertical axis in front of the CCD detector. A high-resolution CT image is obtained after reconstruction using an ordered subsets-expectation maximization (OS-EM) reconstruction algorithm. The SPECT system utilizes a compact semiconductor camera module previously developed in our group. The module is mounted perpendicular to the X-ray tube/CCD combination. It consists of a 64×64 pixellated CdZnTe detector and a parallel-hole tungsten collimator. The field of view is 1 square inch. Planar projections for SPECT reconstruction are obtained by rotating the animal in front of the detector. Gamma-ray and X-ray images are presented of phantoms and mice. Procedures for merging the anatomical and functional images are discussed.
authors.affiliation: Department of Radiology, Division of Nuclear Medicine, University of Arizona, Tucson, AZ 85724 USA.
authors.forename: George A
authors.initials: GA
authors.lastname: Kastis
authors.affiliation: Department of Radiology, Division of Nuclear Medicine, University of Arizona, Tucson, AZ 85724 USA, and also with the Optical Sciences Center, University of Arizona, Tucson, AZ 85721 USA.
authors.forename: Lars R
authors.initials: LR
authors.lastname: Furenlid
authors.affiliation: Department of Radiology, Division of Nuclear Medicine, University of Arizona, Tucson, AZ 85724 USA.
authors.forename: Donald W
authors.initials: DW
authors.lastname: Wilson
authors.affiliation: Institute of Imaging Science, Vanderbilt University, Nashville, TN 37232 USA.
authors.forename: Todd E
authors.initials: TE
authors.lastname: Peterson
authors.affiliation: Department of Radiology, Division of Nuclear Medicine, University of Arizona, Tucson, AZ 85724 USA, and also with the Optical Sciences Center, University of Arizona, Tucson, AZ 85721 USA.
authors.forename: H Bradford
authors.initials: HB
authors.lastname: Barber
authors.affiliation: Department of Radiology, Division of Nuclear Medicine, University of Arizona, Tucson, AZ 85724 USA, and also with the Optical Sciences Center, University of Arizona, Tucson, AZ 85721 USA.
authors.forename: Harrison H
authors.initials: HH
authors.lastname: Barrett
keywords: Biomedical imaging; cadmium zinc telluride (CdZnTe); multimodality imaging; single-photon emission computed tomography; small-animal imaging