Ying Chen, Abstract Co-Author: Nothing to Disclose

Chunguang Zeng, Abstract Co-Author: Nothing to Disclose

Shufeng Fan MD, Presenter: Nothing to Disclose

Xiao Zhu Lin MD, Abstract Co-Author: Nothing to Disclose

yucheng Mi MD,PhD, Abstract Co-Author: Nothing to Disclose

To explore the clinical value of Gemstone Spectral CT Imaging using iodine-based material decomposition images in the diagnosis of pulmonary embolism．

137 patients with suspected PE underwent monochromatic pulmonary CTA using gemstone spectral imaging mode with pitch of 1.375 and fast switching of 80 and 140 kVp on a GE Discovery CT750 HD scanner, Monochromatic image data sets and iodine-based material decomposition images with 0.625-mm slice thickness were reconstructed and processed on the dedicated workstation(Advantage Workstation 4.4, GE).Monochromatic CT angiographic images were reviewed for the identification and localization of pulmonary embolism. The number and location of perfusion defects were also recorded on the iodine maps .The iodine density of perfusion defects and normal lung parenchyma of the same or equivalent level on the iodine maps were measured and compared.．Two independent samples T-test were used to compare iodine density between different groups．

For 96 patients, iodine distribution was homogeneous and CT angiography showed no pulmonary embolism. A total of 401 clots were detected in 41 patients (21 man,20women; mean age 63.90±14.76), with main (n=36), lobar (n=90)，segmental (n=194) and sub-segmental (n=81) distribution. And there were 154 iodine distribution defects along with these clots. There was a significant difference in iodine density between normal lung parenchyma [(23.86±8.99)100μg/L] and iodine distribution defects [(4.86±4.62) 100μg/L] (t=-18.823，P<0．001)．

Iodine mapping of CT spectral imaging is a reliable method in the evaluation of pulmonary embolism including morphologic analysis of PE and quantitative depiction of pulmonary blood flow and perfusion defects.

With iodine mapping,CT spectral imaging can provide morphological and functional information of whole lungs, which plays an important role in the diagnosis and follow-up of PE.

Chen, Y, Zeng, C, Fan, S, Lin, X, Mi, y, The Preliminary Study of Iodine Mapping in the Diagnosis of Pulmonary Embolism Using CT Spectral Imaging.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12043733.html