Ioannis Vlahos MBBS, Presenter: Nothing to Disclose

Christianne Leidecker PHD, Abstract Co-Author: Employee, Siemens AG

Bernard Assadourian BA, RTR, Abstract Co-Author: Nothing to Disclose

Bernhard Schmidt PhD, Abstract Co-Author: Employee, Siemens AG

Michael Macari MD, Abstract Co-Author: Nothing to Disclose

Alec Jeffrey Megibow MD, Abstract Co-Author: Nothing to Disclose

Purpose: To evaluate the feasability and potential clinical utility of single acquisition Dual Energy MDCT (DEMDCT) scanning in patients with selected abdominal diseases. Materials and Methods: DEMDCT scanning was performed using a 64-detector dual source scanner (Somatom Definition, Siemens Medical Systems, Forcheim, GE). Tube A: 80kVp & 490mAs, Tube B: 140kVp & 90mAs; collimation: 64 x 0.6mm, pitch 0.5- 1.0. Post-processing was performed on a workstation using a dedicated experimental software platform (Siemens). Initial 140kVp, 80kVp and fused energy data sets were generated and used for subsequent computed derivation of virtual non-contrast, virtual pure iodine distribution and virtual bone/calcium image data sets. Early DEMDCT studies were restricted to evaluate patients being followed for aortic aneurysm stents, characterization of focal liver or renal lesions and surveillance of cirrhotics. For these different indications the potential clinical impact of evaluating these multiple different image data sets generated from a single DEMDCT examination was assessed. A variety of different combinations of these data sets were fused or subtracted and evaluated by 3-D post processing to establish new methods for evaluating normal anatomy and disease. Results: To date 19 patients have been evaluated. For aortic studies 80kVp data sets resulted in denser opacification of arteries and increased conspicuity of endoleaks compared to 140kVp or fused energy sets. Subtraction data sets (80kVp minus virtual non-contrast) were entirely free of registration artifacts, supplementing angiographic studies. These data sets also permitted characterization of regional hepatic fatty infiltration and characterization of larger focal hepatic and renal lesions such as simple or hyperdense cysts, hemangiomas and neoplastic lesions based on depicted patterns of enhancement without the need for pre-contrast imaging. Conclusion: DEMDCT reflects a completely novel methodology for performing, evaluating and displaying data from CT studies. This initial experience has allowed to create a uniform set of sequences exploiting early capabilities of this technology.

Vlahos, I, Leidecker, C, Assadourian, B, Schmidt, B, Macari, M, Megibow, A, Hot Topic: Initial Clinical Evaluation of Single Acquisition, Dual Energy MDCT: Abdominal Imaging.  Radiological Society of North America 2006 Scientific Assembly and Annual Meeting, November 26 - December 1, 2006 ,Chicago IL. http://archive.rsna.org/2006/8002494.html