Imaging of the Human Torso Using Cone-Beam Transmission CT Implemented on a Rotating Gamma Camera

• Published in: The Journal of nuclear medicine (1978) Vol. 33; no. 1; pp. 150 - 156
• Main Authors: Manglos, Stephen H, Bassano, Daniel A, Thomas, F. Deaver, Grossman, Zachary D
• Format: Journal Article
• Language: English
• Published: United States Soc Nuclear Med 01.01.1992
• Subjects: Body Height; Female; Humans; Liver - diagnostic imaging; Male; Technetium; Thallium Radioisotopes; Thorax - diagnostic imaging; Tomography, Emission-Computed, Single-Photon - methods; Tomography, X-Ray Computed - methods
• ISSN: 0161-5505; 1535-5667

Radionuclide transmission CT generated on a rotating gamma camera can improve SPECT imaging by providing attenuation maps for attenuation compensation and for anatomical correlation. This paper demonstrates the feasibility and high quality of cone-beam transmission CT (CB-CT) of human subjects, in comparison to conventional parallel-ray CT, and evaluates some possible imaging protocols. Two CB-CT implementation modes, with a cone-beam collimator and without any collimator, were evaluated. Three human subjects of different dimensions were imaged. For the two smaller subjects, the CB-CT images were dramatically superior, in terms of noise and resolution, to those obtained with a parallel-ray geometry. The image noise was less by a factor of 6. CB-CT linear attenuation coefficients were found to be in close agreement with published values for various tissues. For the largest subject, image truncation produced a ring artifact at the edge, but inside the artifact, the image quality was still very good. Cone-beam images obtained without any collimator were acceptable, but photon scatter degraded the image contrast.