小肠缺血性肠病的多层螺旋CT诊断

Multi-slice Spiral CT Diagnosis of Ischemic Small Bowel Disease

目的:分析小肠缺血性肠病的多层螺旋CT表现,以提高其CT诊断水平。材料和方法:收集本院19例最终诊断为小肠缺血性肠病并行CT检查的患者,分析其CT表现及病因。除4例急诊检查外,其余15例检查前均口服2.5%等渗甘露醇1000-1500ml作为肠道对比剂,每一例均行平扫、动脉期和静脉期增强扫描,15例行冠状面最大密度投影(MIP)和多平面重组(MPR)后处理。结果:CT表现为肠壁增厚16例(84%),分层强化呈靶征14例(占增厚肠壁87.5%),肠壁菲薄、无强化2例,肠腔扩张、积气、积液14例(73.7%),肠系膜浑浊15例(78.9%),腹水13例,肠壁积气3例,门静脉积气、肠系膜上动脉(SMA)充盈缺损、僵硬狭窄及肠系膜上静脉(SMV)闭塞各1例,肠系膜小血管充血(增粗、密集呈"梳征")16例,缺血(变细、稀疏、强化减弱)3例。病因为系统性红斑狼疮(SLE)引起的血管炎7例,肠梗阻4例,SMA栓塞(均为房颤患者)、肠系膜扭转和外伤分别为2例,动脉粥样硬化、SMV血栓形成各1例。7例SLE均广泛累及十二指肠、空肠及回肠,其中5例同时累及结肠。结论:小肠缺血性肠病的多层螺旋CT表现为:①肠壁和肠系膜缺血:肠壁水肿、增厚、分层强化呈靶征,肠系膜浑浊,血管炎所致缺血性肠病常累及整个小肠及结肠;②肠系膜血管异常:SMA及SMV狭窄或闭塞,肠系膜小血管充血或缺血。

Purpose： To analyze the multi- slice spiral CT findings of ischemic small bowel disease, and to improve the diagnosis accuracy.Materials and Methods： Causes of disease and CT findings of 19 cases of ischemic small bowel disease were analyzed. 15 patients ingested 1000 - 1500ml of 2.5% osmotic mannitol as bowel contrast medium before CT scanning except 4 emergency cases. Every patient received non - enhanced and contrast - enhanced scanning （arterial phase and portal venous phase） and the images of 15 cases were reformatted with coronal maximum intensity projection （MIP） and multiplanar reformation（MPR） . Results： The CT findings included mural thickening（16 cases, 84%） and heterogeneous enhancement with target sign（ 14 cases, 87.5% of mural thickening cases）, mural thinning and lack of enhancement（2 cases）, luminal dilation and filling of air or fluid（14 cases, 73.7% ）, mesenteric fat stranding（15 cases）, ascites（13cases）, intramural pneumatosis（3 cases）, portal venous gas, filling defect and stenosis of superior mesenteric arteries （SMA） and occlusion of superior mesenteric veins（SMV） （ 1 case each）, mesenteric engorgement（increase, denseness and showed comb sign of mesenteric vessels） （16 cases）, mesenteric ischemia（decrease, sparseness and lack of enhancement of mesenteric vessels） （3cases）. The causes of 7 cases were vasculitis affected by SLE, 4 cases were bowel obstruction, 2 cases were embolism of SMA, 2 cases were mesenteric rotation and trauma, 1 case each was atherosclerosis and thrombosis of SMV. 7 cases of SLE all involved extensively duodenum, jejunum and ileum, among which colon were involved simultaneously in 5 cases.Conclusion： The multi - slice spiral CT findings of ischemic small bowel disease include： ①ischemia of bowel wall and mesentery： mural edema and thickening with heterogeneous enhancement as target sign, mesenteric fat stranding,and the ischemic bowel disease caused by vasculitis often involves entire small bowel and colon： ②abnormal mesenteric vessels： stenosis or occlusion of SMA or SMV, engorgement or ischemia of mesenteric vessels.