Fig. 6
From: Practical issues and limitations of brain attenuation correction on a simultaneous PET-MR scanner
Images of the 68Ge daily QC phantom attenuation corrected using a CT provided on the scanner, b GE CT with Siemens HU to LAC scaling and c GE CT with GE HU to LAC scaling. The activity concentration measured in a large ROI located at the centre of the images is shown below each image