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.

DUI

D015899 MeSH Browser

CUI

M0024331

Previous indexing

Tomography, X-Ray Computed (1977-1979); Tomography, Emission-Computed (1980-1989)

History note

90; was SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY & SPECT see TOMOGRAPHY, EMISSION-COMPUTED 1989

Online note

use TOMOGRAPHY, EMISSION-COMPUTED to search SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY & SPECT 1989

Public note

90; was SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY & SPECT see TOMOGRAPHY, EMISSION-COMPUTED 1989