The influence of integrated-CT artifacts on the attenuation correction results of SPECT/CT bone imaging / 中国医学影像技术

ABSTRACT

Objective To evaluate the influence of integrated-CT artifacts on attenuation-corrected (AC) images of SPECT bone imaging. Methods Imaging documents of 78 patients who underwent SPECT/CT bone imaging were retrospectively analyzed, and the artifacts on CT images and CT attenuation maps were visually studied. Compared with the non-attenuation corrected (NC) images, the coefficient of variation (CV) and percentage difference (PD) of radioactive count of regional bone influenced by CT artifacts were calculated and statistically analyzed to estimate the influence of CT artifacts on AC images of SPECT bone imaging. Results The integrated-CT artifacts were found in 38 patients of 78, and appeared the same image findings as those on CT attenuation maps respectively, including truncation artifact, thoraco-abdominal gas artifact, photon starvation artifact, etc. On all the AC images with integrated-CT artifacts, regional bones were influenced not only on uniformity (CVAC 17.62%±4.13%, CVNC 11.19%±3.81%;t=2.13, P<0.05), but also by the distribution (PDAC 16.98%±3.31%, PDNC 9.84%±1.62%;t=2.46, P<0.05) of radioactive count. Conclusion Artifacts on integrated-CT images can induce false AC information on CT attenuation maps, therefore, a comparative analysis with NC images is recommended if necessary.