Multi-Energy CT: Advanced Imaging Practices in Emergency Radiology (2025)-W6-CER11-2025

Video Transcription

Video Summary

Nicholas Murray (UBC emergency radiologist) explains how multi-energy (dual-energy) CT can add value in emergency imaging despite workflow concerns (more reconstructions, longer interpretation). He frames its benefit as moving reports from “indeterminate” toward definite normal/abnormal by improving diagnostic confidence, detecting subtle or invisible findings, expanding CT’s diagnostic boundaries, and preventing errors. Key examples include identifying bone marrow edema to age-indeterminate compression/insufficiency fractures, revealing radiolucent gallstones by using extreme keV virtual monoenergetic images, clarifying etiologies (e.g., gallstone ileus), and distinguishing hemorrhage from calcification on head CT. He advises reading conventional images first, then using multi-energy reconstructions selectively as problem-solving tools, plus a final quick review to avoid misses (e.g., tubal torsion mimicking PID). Implementation requires radiologist buy-in, optimized automatic reconstruction sets, and awareness of pitfalls/overcalling.<br /><br />Gopal Punjabi reviews spectral CT for acute bowel pathology, emphasizing bowel ischemia: iodine maps improve detection of decreased/absent enhancement (“black hole sign”), help identify small arterial/venous occlusions, assess non-occlusive ischemia, and increase confidence without longer read times. He also covers closed-loop obstruction, bucket-handle trauma tears, GI bleed (iodine vs virtual non-contrast), appendicitis necrosis/perforation, and problem solving (hematoma vs mass, delayed contrast in ascites, anastomotic leaks).<br /><br />Alan Yu highlights dual-energy CT for incidental findings, using iodine overlay, virtual monoenergetic images, and virtual non-contrast to improve lesion detection/characterization (liver, gallbladder, pancreas, adrenal, renal/urothelial, GI, vascular tumor thrombus/endoleak) and potentially reduce follow-up imaging—while noting limitations of VNC for adrenal adenomas.

Keywords

dual-energy CT

spectral CT

emergency radiology

virtual monoenergetic imaging

iodine maps

virtual non-contrast

bowel ischemia

hemorrhage vs calcification