MSCTA diagnosis of spontaneous dissection of the superior mesenteric artery

Objective To analyse cases of spontaneous dissection of the superior mesenteric artery for better understanding of this disease.Methods Five emergency cases(4 males and 1 female,aged 46~78,with an average age of 56.4) were chosen from the time from Oct.2008 to Aug.2010.TOSHIBA AQUILION 16-Slice Spiral CT or GE Lightspeed 64-Slice VCT was applyed for scanning,ranging from aortic arch to pubic symphysis.Scanning conditions were as follows 120 kV,300 mA,1 mm slice thickness or 120 kV,500 mA,0.625 mm slice thickness.100 ml iohexol(350 mgI/ml) was injected from the elbow vein at 3.5 ml/s.Tracking injection of 40 ml normal saline was made at the same rate.23 s was delayed before scanning.After scanning,image was reconstructed with 1 or 0.625 mm slice thickness and transmited it to workstation.The artery was observed by VR,CPR and MIP etc.Results The reconstructed images of all the five cases clearly showed the superior mesenteric artery and its branches.The axial scan showed the true and false lumen in the superior mesenteric artery,similar to that in the aortic dissection,and clearly showed the intimal flap of low density.CPR and MPR can also show strip filling defect of low density and clearly show the intimal flap.VR image can show double lumen change.MIP image was similar to VR image.Every case of the five only showed one cleft,different from aortic dissection which showed two or more clefts.One case had distal superior mesenteric artery embolism,complicated with common hepatic artery aneurysm.One case had subterminal and distal superior mesenteric artery embolism.One case was complicated with right renal artery branch dissection.Conclusion MSCTA can early and accurately diagnose superior dissection of the mesenteric artery.