TY - JOUR
T1 - First results from the high-resolution mouseSPECT annular scintillation camera
AU - Goertzen, Andrew L.
AU - Jones, Douglas W.
AU - Seidel, Jurgen
AU - Li, King
AU - Green, Michael V.
N1 - Manuscript received July 15, 2004; revised November 29, 2004. This work was supported by the Clinical Center of the National Institutes of Health. The Associate Editor responsible for coordinating the review of this paper and recommending its publication was R. Jaszczak. Asterisk indicates corresponding author. *A. L. Goertzen was with the Imaging Physics Laboratory, Clinical Center, National Institutes of Health, Bethesda, MD 20892 USA. He is now with the McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal QC H3A 2B4, Canada (e-mail: [email protected]).
PY - 2005/7
Y1 - 2005/7
N2 - High-resolution single-photon emission computed tomography (SPECT) imaging in small animals tends to use long imaging times and large injected doses due to the poor sensitivity of single pinhole gamma cameras. To increase sensitivity while maintaining spatial resolution, we designed and constructed a multipinhole collimator array to replace the parallel hole collimators of a Ceraspect human SPECT brain scanner. The Ceraspect scanner is composed of an annular NaI(Tl) crystal within which the eight pinhole collimators (1-mm-diameter holes) rotate while projecting nonoverlapping images of the object onto the stationary annular crystal. In this manner, only one-eighth of a collimator rotation is required to acquire a full circle orbit tomographic data set. The imaging field of view (FOV) has a diameter of 25.6 mm in the transverse direction, which is sufficient to encompass a mouse in the transverse direction. The axial FOV is 25.6 mm at the center of the FOV and 13. 9 mm at the edge of the transverse FOV. Data are currently acquired in step-and-shoot mode; however, the system is capable of list mode acquisition with the collimator continuously rotating. Images are reconstructed using a cone-beam ordered sub-sets expectation maximization method. The reconstructed spatial resolution of the system is 1.7 mm and the sensitivity at the center of the FOV is 13.8 cps/microCi. A whole-body bone scan of a mouse injected with [Tc-99 m]MDP clearly revealed skeletal structures such as the ribs and vertebral bodies. These preliminary results suggest that this approach is a good tradeoff between resolution and sensitivity and, with further refinement, may permit dynamic imaging in living animals.
AB - High-resolution single-photon emission computed tomography (SPECT) imaging in small animals tends to use long imaging times and large injected doses due to the poor sensitivity of single pinhole gamma cameras. To increase sensitivity while maintaining spatial resolution, we designed and constructed a multipinhole collimator array to replace the parallel hole collimators of a Ceraspect human SPECT brain scanner. The Ceraspect scanner is composed of an annular NaI(Tl) crystal within which the eight pinhole collimators (1-mm-diameter holes) rotate while projecting nonoverlapping images of the object onto the stationary annular crystal. In this manner, only one-eighth of a collimator rotation is required to acquire a full circle orbit tomographic data set. The imaging field of view (FOV) has a diameter of 25.6 mm in the transverse direction, which is sufficient to encompass a mouse in the transverse direction. The axial FOV is 25.6 mm at the center of the FOV and 13. 9 mm at the edge of the transverse FOV. Data are currently acquired in step-and-shoot mode; however, the system is capable of list mode acquisition with the collimator continuously rotating. Images are reconstructed using a cone-beam ordered sub-sets expectation maximization method. The reconstructed spatial resolution of the system is 1.7 mm and the sensitivity at the center of the FOV is 13.8 cps/microCi. A whole-body bone scan of a mouse injected with [Tc-99 m]MDP clearly revealed skeletal structures such as the ribs and vertebral bodies. These preliminary results suggest that this approach is a good tradeoff between resolution and sensitivity and, with further refinement, may permit dynamic imaging in living animals.
KW - Micro SPECT
KW - Mouse imaging
KW - Pinhole SPECT
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U2 - 10.1109/TMI.2005.843782
DO - 10.1109/TMI.2005.843782
M3 - Article
C2 - 16011315
AN - SCOPUS:23744441912
SN - 0278-0062
VL - 24
SP - 863
EP - 867
JO - IEEE transactions on medical imaging
JF - IEEE transactions on medical imaging
IS - 7
ER -