Quantitative SPECT by attenuation correction of the projection set using transmission data: evaluation of a method.
A method for measuring attenuation coefficients in single-photon emission tomography (SPECT) is described and evaluated, together with a method for attenuation correction using these measured attenuation coefficients. Build-up, caused by scattered photons, is corrected for by a simple substitution in the algorithms. Transmission studies are performed with a 99mTc- or 57Co flood source, and emission phantom studies with 99mTc line sources. The method is evaluated with variable but well-defined phantoms. The result is accurate attenuation coefficients for different densities, dimensions and geometries, and an accuracy of corrected emission activities of better than +/- 10% in most cases. The present limitations of the method for attenuation correction are discussed.
Almquist
H
H
Department of Clinical Physiology, University of Lund, Sweden.
Palmer
J
J
Ljungberg
M
M
Wollmer
P
P
Strand
S E
SE
Jonson
B
B
D000465:Algorithms; D003037:Cobalt Radioisotopes; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008961:Models, Structural; D013667:Technetium; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
D003037:Cobalt Radioisotopes; D013667:Technetium