LEARNING OBJECTIVES: (1) To review the basic principles and advantages of dual energy CT (DECT) imaging (2)	To review applications of DECT in abdominal and urogenital imaging (2.a) Characterizing composition of renal calculi (2.b) Detecting radio-opaque gallstones (2.c) Assessing bowel perfusion (3)	To review applications of DECT in neuroradiology (3.a)	Differentiating hemorrhage from contrast medium (3.b)	Reducing beam hardening artifact, particularly in relation to the posterior fossa, and metallic artifact (4)	To review applications of DECT in cardio-thoracic imaging (4.a) Assessing parenchymal perfusion in CT PE. BACKGROUND: Dual energy CT (DECT) enables simultaneous scanning at two different energy levels, which facilitates material characterization on CT such as the composition of renal stones and detection of iodine-based contrast. Through unique three-material decomposition, we can subtract iodine or calcium from images to quantify the amount of iodine in one voxel, assess perfusion and differentiate hemorrhage from iodine. This exhibit aims to explore and highlight some applications of DECT in everyday practice across multiple subspecialties. CONCLUSION: DECT augments what conventional single energy CT can do with a wide array of applications in abdominal, neuroradiological, and cardiothoracic imaging through material characterization and three-material decomposition as outlined in this exhibit. Ultimately, this helps improve diagnostic accuracy and expand our diagnostic capability, with the potential for positive impact on patient care.

Dual Energy CT, Blood, Bones and Stones