多层螺旋CT观测正常膈下动脉起源和直径

MSCT observation of origin and diameter of inferior phrenic artery

目的采用MSCT观测国人正常膈下动脉(IPA)的起源及直径,为血管造影和手术提供参考依据。方法对300名受试者行上腹部增强扫描,对比剂为碘海醇(320mgI/ml)。对所得图像进行CPR、MIP及VR,比较3种重建方法对IPA起源及大体解剖的显示能力,并在MIP图像上测量IPA直径(距离起源开口5mm处)。结果 300名受检者清晰显示594支IPA,其中300支(50.51%)起始于腹腔干,208支(35.02%)起始于腹主动脉,56支(9.43%)起始于肾动脉,20支(3.37%)起始于胃左动脉,7支(1.18%)起始于副肾动脉,2支(0.34%)起始于肝固有动脉,1支(0.17%)起始于脾动脉。3种重建方式显示IPA的差异无统计学意义(P>0.05)。右侧IAP直径为(1.41±0.33)mm,95%可信区间(1.41±0.04)mm;左侧IPA直径为(1.30±0.37)mm,95%可信区间(1.30±0.04)mm。结论 MSCT可较好地反映IPA的正常解剖和变异,并可提供其内径的正常参考值。

Objective To observe the origin and the diameter of the normal inferior phrenic artery （IPA） with MSCT, in order to provide references for angiography and surgery. Methods Abdominal MSCT angiography was performed in 300 subjects without hepatic pathologies using contrast media iohexol contained 320 mg iodine/ml. The data were postprocessed with curved planar reconstruction （CPR）, maximum intensity projection （MIP） and volume rendering （VR） techniques. The capacity of CPR, MIP and VR in displaying the origin and the main anatomy of IPA was compared, and the diameter of IPA was measured 5 mm from the origin point on the MIP images. Results Totally 594 IPA were displayed clearly in 300 subjects, of which 300 IPA （50.51%） were from celiac trunk, 208 （35.02%） from abdominal aorta, 56 （9. 43%） from renal artery, 20 （3.37%） from left gastric artery, 7 （1.18%） from accessory renal artery, 2 （0.34%） from proper hepatic artery and 1 （0.17%） from splenic artery. No statistical difference of CPR, MIP and VR in displaying the IPA was found （P〉0.05）. The diameter of right IPA was （1.41±0.33）mm, with 95G confidence interval of （1. 41±0.04）mm, of left IPA was （1.30±0.37）ram, with 95% confidence interval of （1.30±0.04）mm. Conclusion MSCT can depict ana- tomic characteristics of IPA and its variants, and provide reference for normal value of diameter.