Experimental Study of Acute Superior Mesenteric Artery Embolism with Dual Enery CT Intestines Iodine Maps in Dogs

Objective To investigate the feasibility and accuracy of dual energy CT intestines iodine maps in decting acute superior mesenteric artery embolism in dog model.Methods At first,all 8 experimental dogs were underwent both unenhanced and enhanced abdomen DSCT scans,then,acute superior mesenteric artery embolism model of dogs were established by DSA,2 dogs of control group were only injected 10ml Sodium Chloride.All dogs were underwent dual energy scans by DSCT in 6~8-hours after embolization.At last,6 model dogs were dissected,gross changes of bowel ischemia,scissor necrotic bowel were observed and delivered to pathologic examination.The thin slice reconstruction data was analyzed by using double energy perfusion software.Dog's bowel was segmented into 9 sections from duodenum to rectum and observed.The difference of contrast enhancement value and CT value of infarct region before and after embolization were compared using t test.Sensitivity,specificity and concordance of diagnosis of intestines infarction were evaluated by MSCT and DSCT intestines idoine maps.Results Statistics of 17 types of CT signs on DSCT had better spatial and density resolution than that on MSCT.Perfusion quantitative analysis demonstrated that the contrast enhancement value of normal intestines were(107.23±12.27)HU、(110.33±17.78) HU before and after embolization.There was no significant difference between them(t=-0.491,P=0.635).The CT value of infarcted gut before and after embolization were 141.42±23.81,76.17±7.68.There was significant difference between them(t=4.29,P=0.023);The contrast enhancement value were(108.43±8.82)HU,(36.40±6.67)HU,There was significant difference between them(t=14.384,P=0).Good concordance was existed between MSCT,DSCT and pathology by Kappa analysis,K value of DSCT was highter then that of MSCT.Conclusion DSCT intestines iodine maps is suitable to detect acute superior mesenteric artery embolism,its accuracy and sensitivity are slightly higher than that by MSCT.