LEARNING OBJECTIVES: (1)	To review the principles of dual energy CT imaging (2)	To review the role of DECT in the detection of monosodium urate crystal deposition (3)	To review how DECT can aid in the reducing metal artifacts (4)	To review key applications of dual energy CT in assessing soft tissue tendons, ligaments and joints: (4.a) Identifying bone marrow edema (4.b) Using DECT for Tendon assessment. BACKGROUND: In this exhibit, we will discuss unique applications of dual energy computer tomography (DECT) in musculoskeletal imaging including detection of uric acid deposits and reduction of metal artifact. The applications of DECT go beyond assessment of bony structures. DECT can be used to assess bone marrow edema through subtraction of calcium from cancellous bone. In addition, ligaments and tendons can be assessed using DECT by differentiating collagen, water, and soft tissue from other structures. CONCLUSION: DECT is a technology that combines some of the capabilities of MR imaging with CT as detailed in this exhibit. Additionally, DECT extends beyond the capabilities of conventional single energy CT and MR with unique features such as the ability to identify uric acid crystals and reduce metal prosthetic artifact. Magnetic resonance imaging (MRI) remains the gold standard for visualization of soft tissue and bone marrow. However, DECT can also play a role in assessing soft tissue including tendons and bone marrow edema in settings where MRI is not promptly available with the added benefit of faster acquisition times. DECT has the potential to expand our diagnostic capabilities and accuracy in musculoskeletal imaging which ultimately has the potential to positively impact patient care.

Dual energy CT in Musculoskeletal Imaging, Crystals and Soft tissue