Hybrid Imaging of Peripheral Skeletal Disease by SPECT/High-Resolution Flat-Panel CT

Abstract

The aim of this study was to determine the impact of high-resolution cone-beam CT with flat-panel detectors on the interpretation of bone SPECT in diseases of the peripheral skeleton. Forty-one consecutive patients with peripheral skeletal disease were examined with a SPECT/high-resolution CT system providing isotropic voxels of 0.33 × 0.33 × 0.33 mm. High-resolution images were retrospectively analyzed by 2 readers and compared with low-resolution images obtained by filtering the high-resolution images to a lower resolution. SPECT/high-resolution CT demonstrated higher diagnostic confidence scores (1.98 ± 0.27 vs. 1.3 ± 0.45, P < 0.01) and better interobserver agreement (κ = 0.5 vs. 0.2) than SPECT/low-resolution CT. The diagnosis made by SPECT/high-resolution CT was in agreement with the final clinical diagnosis in 95% (reader 1) and 90% (reader 2) of the cases, as compared with 59% (reader 1) and 60% (reader 2) of the cases for SPECT/low-resolution CT (P < 0.01). High-resolution flat-panel CT has the potential to significantly improve SPECT/CT imaging in diseases of the peripheral skeleton.