A method of computed tomography that uses radionuclides which emit a single photon of a given energy. The camera is rotated 180 or 360 degrees around the patient to capture images at multiple positions along the arc. The computer is then used to reconstruct the transaxial, sagittal, and coronal images from the 3-dimensional distribution of radionuclides in the organ. The advantages of SPECT are that it can be used to observe biochemical and physiological processes as well as size and volume of the organ. The disadvantage is that, unlike positron-emission tomography where the positron-electron annihilation results in the emission of 2 photons at 180 degrees from each other, SPECT requires physical collimation to line up the photons, which results in the loss of many available photons and hence degrades the image
Computed tomography where there is continuous X-ray exposure to the patient while being transported in a spiral or helical pattern through the beam of irradiation. This provides improved three-dimensional contrast and spatial resolution compared to conventional computed tomography, where data is obtained and computed from individual sequential exposures
Computed tomography where there is continuous X-ray exposure to the patient while being transported in a spiral or helical pattern through the beam of irradiation. This provides improved three-dimensional contrast and spatial resolution compared to conventional computed tomography, where data is obtained and computed from individual sequential exposures
Catacombs -- Congresses : The conservation of subterranean cultural heritage / editor, Cesareo Saiz-Jimenez, Instituto de Recursos Naturales y Agrobiologia, Consejo Superior de Investigaciones Cientificas (IRNAS-CSIC), Sevilla, Spain
2014
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Catacombs -- France -- Paris : Cities of the underworld. Season 1, episode 5, Catacombs of death / producer, Allison Hynes ; produced by Authentic Entertainment, Inc. in association with Thirty Four Productions, LLC for the History Channel