LAUSR

OBJECTIVES To evaluate the benefits and clinical significance of retrospectively generated spectral image-datasets with the novel detector-based Spectral CT (SDCT). METHODS A total of 118 body CTs from the SDCT prototype were included. Based on the clinical indication, two radiologists were asked if they would have opted for a dual-energy mode/scan if the patient was scanned in one of the other commercially-available dual-energy scanners, which need prospective selection of dual energy mode. They also reviewed the scans, identified cases that would benefit from spectral images and evaluated these images for clinical utility and significance on a five-point scale, with 1 being the least and 5 being the highest. RESULTS Dual-energy mode would have been prospectively selected in 20 cases (17%) for Reader 1 and 25 cases (21%) for Reader 2. Additional spectral images were requested for 94 cases (80%) and 96 cases (81%) respectively. A total of 196 and 206 spectral image-sets were utilized respectively with 97% and 96% of these image-sets useful retrospectively. The distribution of scores on the five-point scale for Readers 1 and 2 were, 1-7% & 6%; 2-26% & 30%; 3-36% & 36%; 4-27% & 21% and; 5-4% & 7%. Clinically significant score (≥4) was noted in 31% and 28% respectively. CONCLUSIONS Additional spectral datasets retrospectively reconstructed from SDCT enhanced the diagnostic capabilities by reducing artifacts, improving contrast and allowing lesion characterization.