MSCT评估正中弓状韧带压迫腹腔动脉的发生率及其特征

MSCT in evaluation of occurrence rate of celiac artery compressed by median arcuate ligament and its characteristics

目的 探讨MSCT评估正中弓状韧带（MAL）压迫腹腔动脉（CA）的发生率及其特征。方法 选取接受腹部增强CT或腹主动脉CTA检查的患者1 114例,观察CA有无狭窄并分析其狭窄原因。对MAL压迫CA的患者,观察CA是否存在狭窄后扩张和侧支循环,测量CA最狭窄处血管腔直径、狭窄后远段正常血管腔直径、狭窄段长度、狭窄段起始与腹主动脉的距离及最狭窄处与腹主动脉的距离,并计算CA血管狭窄率;进行统计学分析。结果134例（134/1 114,12.03%）为MAL压迫CA,男、女发生率差异无统计学意义（77/617,12.48%;57/497,11.47%;χ~2=0.266,P=0.606）,各年龄段CA发生率的差异无统计学意义（χ~2=2.279,P=0.809）,各年龄段男、女发生率的差异亦无统计学意义（P均〉0.05）。MAL压迫CA患者的CA血管狭窄率为16.36%~95.74%,其中轻微狭窄占3.73%（5/134）,轻度狭窄占42.54%（57/134）,中度狭窄占38.06%（51/134）,重度狭窄占15.67%（21/134）。39例（39/134,29.10%）伴狭窄后扩张;11例（11/134,8.21%）伴侧支循环,且CA血管狭窄率均〉65%。2例（2/134,1.49%）有MAL压迫综合征。CA血管狭窄率与狭窄段长度呈正相关（r=0.45,P〈0.01）,与最狭窄处与腹主动脉的距离亦呈正相关（r=0.187,P=0.03）,但与狭窄段起始与腹主动脉的距离无相关性（P〉0.05）。结论 MAL压迫CA在各年龄段及性别中的发生率无明显差异。MSCT结合图像重建及三维重建可无创诊断MAL压迫CA。

Objective To explore MSCT in evaluation of occurrence rate of celiac artery （CA） compressed by median arcuate ligament （MAL） and its characteristics.Methods Totally 1 114 patients accepted abdominal enhance CT and aorta abdominalis CTA examination. Whether CA was stenosis or not was observed, and the cause for stenosis was analyzed. For the patients with CA compressed by MAL, if there were poststenotic dilatation and collateral vessels was observed. Diameter of the narrowest vessel lumen of CA, diameter of normal vessel lumen following stenosis, length of stenotic part, distance from starting point of stenosis to aorta abdominalis, distance from the narrowest point to aorta abdominalis were measured. The percentage of stenosis rate of CA was calculated, and the data were analyzed statistically.Results All of 134 cases （134/1 114, 12.03%） had CA compressed by MAL. The incidence rate difference of male and female had no statistical significance （77/617, 12.48%; 57/497, 11.47%; χ^2=0.266, P=0.606）. The incidence rate difference of different age group had no statistical significance （χ^2=2.279, P=0.809）. The incidence rate difference of male and female in different age group also had no statistical significance （both P〉0.05）. The stenosis ratio of CA compressed by MAL was 16.36%-95.74%. Minimal stenosis took up 3.73% （5/134）, mild stenosis took up 42.54% （57/134）, moderate stenosis took up 38.06% （51/134）, severe stenosis took up 15.67% （21/134）. Thirty-nine cases （39/134, 29.10%） had poststenotic dilatation. Eleven cases （11/134, 8.21%） had collateral vessels, and stenosis rate of CA was more than 65%. Two cases were diagnosed with MAL syndrome. Stenosis rate of CA was positively correlated with length of stenotic part （r=0.45, P〈0.01） and distance from the narrowest point to aorta abdominalis （r=0.187, P=0.03）. There was no correlation between stenosis rate of CA and distance from starting point of stenosis to aorta abdominalis （P〉0.05）.Conclusion The incidence rate of CA compressed by MAL has no vary significance according to sex and age. MSCT combined with reorganized and three-dimensional reconstructed images can be used to noninvasively diagnose CA compressed by MAL.