Alexander André Fingerle MD, Presenter: Nothing to Disclose

Naama Rachel Bogot MD, Abstract Co-Author: Research Consultant, Siemens AG

Galit Kafri PhD, Abstract Co-Author: Nothing to Disclose

Jacob Sosna MD, Abstract Co-Author: Consultant, ActiViews Ltd Research grant, Koninklijke Philips Electronics NV

To prospectively evaluate the use of iodine distribution maps acquired with a dual-layer dual-energy MDCT to detect pulmonary embolism in the entire chest including the lung periphery.

In this prospective study pulmonary CT angiography was performed in 40 patients referred for exclusion of pulmonary embolism on a dual-layer dual-energy MDCT (Orion N, Philips Healthcare, Cleveland, OH) allowing simultaneous acquisition of two energy windows. Three sets of images (low, high energy and conventional CT) were automatically generated. Conventional CT images were assessed by an experienced thorax radiologist (>15 years of experience) for pulmonary pathologies. Iodine distribution maps were generated from the low and high energy images giving a qualitative estimation of iodine concentration in the lungs including the entire chest as well as lung periphery. Image quality of pulmonary CTA/iodine distribution maps were subjectively graded (1:excellent, 5:poor). Iodine distribution maps were then assessed for perfusion defects and compared to findings in conventional CT images.

Iodine distribution maps could be obtained for all patients including the entire chest with visualization of peripheral lung parenchyma with iodine. Subjective image quality of pulmonary CTA/iodine distribution maps was rated as 2 and 2.5 respectively. Pulmonary embolism was present in four patients. The perfusion defect in the iodine distribution map was consistent with the peripheral lung area affected by pulmonary embolism.

Iodine distribution maps obtained from simultaneously acquired high and low energy images using dual-layer dual-energy MDCT allow detection of perfusion defects in the entire chest including lung periphery caused by pulmonary embolism.

Dual-layer MDCT is a new technical approach allowing dual-energy imaging of the lungs for the detection of pulmonary embolism being a first step towards multi-energy detectors.

Fingerle, A, Bogot, N, Kafri, G, Sosna, J, Evaluation of a Dual Layer Dual Energy MDCT in Imaging of Pulmonary Embolism Using Iodine Distribution Maps.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9006224.html