Impact of Dual-Energy CT in the Emergency Department: Increased Radiologist Confidence, Reduced Need for Follow-Up Imaging, and Projected Cost Benefit.

OBJECTIVE. The purpose of this study was to analyze the contribution of dual-energy CT (DECT) to radiologist interpretation in the emergency department (ED) to determine whether recommendations for follow-up imaging decrease. MATERIALS AND METHODS. Reports of all DECT studies performed in an ED in 2016 were reviewed. A board-certified radiologist noted the number of times a report indicated that use of DECT techniques contributed to radiologist interpretation. For studies containing DECT findings in the report, the mixed datasets, representing conventional CT images, were read again separately. The difference between the numbers of follow-up studies recommended after conventional CT and DECT was converted into U.S. dollars by use of the Medicare fee schedule to estimate a projected cost benefit due to any reduction in follow-up imaging. RESULTS. The study included 3159 cases. DECT findings potentially altered management in 298 (9.4%) cases, increased diagnostic confidence in 455 (14.4%) cases, provided relevant information in 174 (5.6%) cases, helped characterize an incidental finding in 44 (1.4%) cases, and were mentioned to be noncontributory in three (0.09%) cases. DECT was not mentioned in the report in 2272 cases (71.9%). DECT findings avoided 162-191 recommended follow-up MRI examinations, 21-28 CT examinations, and 2-25 US examinations compared with conventional CT alone. The DECT findings also prompted one additional recommended interventional angiography procedure, one ventilation-perfusion scan, and one imaging-guided biopsy. The projected net cost reduction was $52,991.53-61,598.44. CONCLUSION. DECT added value to routine ED imaging by increasing diagnostic confidence, leading to a reduction in the number of recommended follow-up studies and a projected cost benefit.