Click on image to view larger version.
FIGURE 2. Phantom study for validation of correction algorithm for PVEs. (A–D) SPECT images for Hoffman phantom before and after PVE correction. Division of original SPECT image (A) for Hoffman 3D brain phantom by MR image convoluted with point spread function of SPECT scanner (B) provided SPECT image corrected for PVEs (C). Correction map (D) was created by division of SPECT image corrected for PVEs (C) by original SPECT image (A). PVE correction provided much more homogeneous tracer distribution throughout phantom than that in original SPECT. (E and F) Relationship between regional SPECT counts and regional gray-matter volume in Hoffman phantom. (E) Regional SPECT counts showed linear correlation with regional volume obtained from convoluted MRI before PVE correction in scatter plots. (F) After PVE correction, linear relationship became flat, which indicates independence of SPECT counts from regional volume.
