Evaluation of 2 scatter correction methods using a striatal phantom for quantitative brain SPECT.

Douglass C Vines; Masanori Ichise; Jeih-San Liow; Hiroshi Toyama; Robert B Innis

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PubMed · 12968046

Evaluation of 2 scatter correction methods using a striatal phantom for quantitative brain SPECT.

Douglass C Vines·Masanori Ichise·Jeih-San Liow·Hiroshi Toyama·Robert B Innis

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Abstract

OBJECTIVE: Scatter correction is an important factor in quantitative SPECT. In this study, we evaluated 2 methods of scatter correction for brain SPECT. The first is based on thresholding the energy spectrum (ES), and the second is based on a modification of the transmission-dependent convolution subtraction (TDCS) method. METHODS: SPECT imaging of a skull striatal phantom was performed using a triple-head camera with and without scatter correction. The striatal compartments were filled with (123)I, and the brain shell cavity (background) was filled with varying concentrations of (123)I to obtain striatal-to-background ratios of 2, 5, 10, 15, 20, and 25 to 1, respectively, which were considered to be the expected ratios. SPECT-measured ratios of striatal-to-background counts were determined with scatter correction (both ES and TDCS methods) and without scatter correction and were then compared with the expected ratios. RESULTS: Without scatter correction, measured striatal-to-background ratios were underestimated by an average of 41.7%, compared with the expected ratios. The ES method of scatter correction underestimated the striatal-to-background ratios by an average of 27.4%, a significant improvement (P < 0.04) over those without scatter correction. With the TDCS method of scatter correction, the ratios were underestimated by only 3.3% (P < 0.03). TDCS ratios were significantly (P < 0.04) higher than ES ratios and were nearly identical to the expected ratios. CONCLUSION: These results suggest that scatter correction significantly improves the striatal-to-background ratios. The TDCS method appears to correct scatter more effectively than does the ES method for the striatal phantom, thus providing more accurate quantification.

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Algorithms Corpus Striatum Humans Image Enhancement Phantoms, Imaging Scattering, Radiation Tomography, Emission-Computed, Single-Photon Comparative Study Evaluation Study Journal Article Research Support, Non-U.S. Gov't Validation Study

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Douglass C Vines, Masanori Ichise, Jeih-San Liow, Hiroshi Toyama, Robert B Innis. 2003. Evaluation of 2 scatter correction methods using a striatal phantom for quantitative brain SPECT.. https://pubmed.ncbi.nlm.nih.gov/12968046/

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