Photon scatter is one of the most important factors degrading
the quantitative accuracy of SPECT images. Many scatter
correction methods have been proposed. The single isotope
method was proposed by us.
AIM: We evaluate the scatter
correction method of improving the quality of images by
acquiring emission and transmission data simultaneously with
single isotope scan.
METHOD: To evaluate the proposed scatter
correction method, a contrast and linearity phantom was
studied. Four female patients with fibromyalgia (FM) syndrome
and four with chronic back pain (BP) were imaged.
Grey-to-cerebellum (G/C) and grey-to-white matter (G/W) ratios
were determined by one skilled operator for 12 regions of
interest (ROIs) in each subject.
RESULTS: The linearity of
activity response was improved after the scatter correction (r
= 0.999). The y-intercept value of the regression line was
0.036 (p < 0.0001) after scatter correction and the slope was
0.954. Pairwise correlation indicated the agreement between
nonscatter corrected and scatter corrected images.
Reconstructed slices before and after scatter connection
demonstrate a good correlation in the quantitative accuracy of
radionuclide concentration. G/C values have significant
correlation coefficients between original and corrected data.
CONCLUSION: The transaxial images of human brain studies show
that the scatter correction using single isotope in
simultaneous transmission and emission tomography provides a
good scatter compensation. The contrasts were increased on all
12 ROIs. The scatter compensation enhanced details of
Yang J, Kuikka JT, Vanninen E, Kauppinen T, Lansimies E, Patomaki L