肠系膜上动脉夹层的MSCTA诊断及平扫管径变化的临床意义

The value of multi-slice computed tomography angiography in diagnosis of spontaneous isolated dissection of superior mesenteric artery and the clinical significance of diameter change of superior mesenteric artery on nonenhancement

目的探讨多层螺旋CT血管成像MSCTA诊断肠系膜上动脉夹层(SISMAD)的价值及SISMAD在MSCT平扫时管径变化。方法选取25例SISMAD患者的CT影像资料,对病变进行MSCTA形态学分型;MSCT平扫时在胰头钩突水平测量肠系上动脉(SMA)管径大小。选取腹部MSCT正常的20例作为对照组,比较MSCT平扫时SISMAD组与对照组SMA管径大小,并与肠系膜上静脉(SMV)比较。结果SISMAD分型包括:I型4例(16%),IIa型6例(24%),IIb型13例(52%),III型2例(8%);4例在SMA与肠系膜下动脉(IMA)之间见侧支循环动脉。平扫SISMAD组和正常组SMA管径分别为(11.75±1.29)mm和(7.10±0.97)mm,前者明显大于后者,二者差异有统计学意义(P=0.001),且略大于SMV管径,但差异无统计学意义(P=0.142)。结论MSCTA能很好地显示SISMAD的形态特征,且能准确地显示侧支循环血管情况,为治疗方案选择提供依据;SMA管径扩大是SISMAD在MSCT平扫中的重要征象,SMV管径可作为判断SMA管径扩大的参考值。

Objective To investigate the value of multi-slice computed tomography angiography(MSCTA)in diagnosis of spontaneous isolated superior mesenteric artery dissection(SISMAD)and to evaluate the diameter changes of superior mesenteric artery(SMA)in SISMAD on MSCT nonenhancement.Methods The manifestations of twenty five SISMAD in MSCTA were retrospectively analyzed and classified according to its imaging features,the diameter of SMA in SISMAD was measured at the level of the uncinate process of the pancreatic head.Twenty patients with normal abdominal MSCT were selected as the normal control group.The diameter of SMA between the SISMAD group and the normal group was compared,also,the diameter of SMA in SISMAD group was compared with the superior mesenteric vein(SMV).Results The findings of SISMAD were shown as follows:type I in 4 cases(16%),type IIa in 6 cases(24%),type IIb in 13 cases(52%),type III in 2 cases(8%),and collateral circulation artery between SMA and inferior mesenteric artery(IMA)in 4 cases.The diameter of SMA in SISMAD group and normal group was(11.75±1.29)mm and(7.10±0.97)mm respectively,that of SMV was(10.75±1.60)mm in SISMAD group.The diameter of SMA in SISMAD group was significantly larger than that of normal group(P=0.000),and slightly larger than that of SMV with no significant difference(P=0.142).Conclusion 1)MSCTA can display well not only the morphological characteristics of SISMAD,but also the collateral circulation accurately,which provides the valuable information for the selection of treatment options;2)The enlargement of SMA diameter on nonenhancement MSCT scanning is an important sign of SISMAD,and the SMV diameter can be used as a reference value to judge the enlargement of SMA diameter.