Investigation of the relationship between linear attenuation coefficients and CT Hounsfield units using radionuclides for SPECT

This study has investigated the relationship between linear attenuation coefficients (mu) and Hounsfield units (HUs) for six materials covering the range of values found clinically. Narrow-beam mu values were measured by performing radionuclide transmission scans using Tc-99m, I-123, I-131, Tl-201 and In-111. The mu values were compared to published data. The relationships between mu and HU were determined. These relationships can be used to convert computed tomography (CT) images to mu-maps for single photon emission computed tomography (SPECT) attenuation correction. (C) 2008 Elsevier Ltd. All rights reserved.