肠系膜上动脉夹角测量对“胡桃夹”综合征的诊断探讨

目的应用64排螺旋CT血管成像研究“胡桃夹”患者与正常对照组肠系膜上动脉与腹主动脉夹角以及左肾静脉受压情况，探讨螺旋CT血管成像在诊断“胡桃夹”综合征方面的临床应用意义。方法使用64排多层螺旋CT，回顾性观察134例正常检查者及4例“胡桃夹”综合征患者肠系膜上动脉与腹主动脉夹角的大小，左肾静脉水平肠系膜上动脉与腹主动脉之间的距离，左肾静脉最窄内径及左肾门左肾静脉最宽内径，以明确正常人肠系膜上动脉与腹主动脉夹角的大小对左肾静脉形态的影响，并计算出正常人肠系膜上动脉与腹主动脉夹角的参考范围。结果134例正常人中，肠系膜上动脉与腹主动脉的夹角为49．8°±26．2°，“胡桃夹”综合征患者为25．3°±8．0°;正常人左肾静脉水平肠系膜上动脉与腹主动脉距离为（1．26±0．72）cm，“胡桃夹”综合征患者为（0．58±0．21）cm，差别均有统计学意义。正常人肠系膜上动脉与腹主动脉夹角的大小影响左肾静脉的形态，漏斗型左肾静脉（左肾门区左肾静脉最宽内径与左肾静脉最窄内径的比值〉3）的出现率在肠系膜上动脉与腹主动脉夹角〈35°时为30．6%（（15／49），〉35°时为4．7％（4／85），两组有显著差异（P〈0．05）。结论64排多层螺旋CT清楚显示肠系膜上动脉与腹主动脉的夹角以及左肾静脉受压情况。

Evaluation of the diagnosis of nutcracker syndrome by measuring the angle of superior mesenteric artery

Objective To study the angle of superior mesenteric artery （SMA） and abdominal aorta （AA） and the compression of left renal vein （LRV） using 64 slices multislice spiral computer tomography in normal and nutcracker syndrome,and to discuss the clinical application significance in the diagnosis of the nutracker syndrome by CT（computer tomography） angiography. Methods The angle of SMA and AA ,the distance between them at the level of LRV, the most narrow and the most wide at the hilus of the left kidney of 134 normal persons and 4 patients with nutcraker syndrome were studied.The shape of left renal vein （LRV） effected by the angle of superior mesenteric artery （SMA） and abdominal aorta （AA） in normal persons was studied to calculate the mean angle of SMA and AA in normal persons, Results In 134 nomal persons, the mean angle of SMA was 49.8°±26.2° while in 4 patients with nutcracker syndrome the mean angle of AA was 25.3°± 8.0° , The mean distance between SMA and AA at the level of LRV was （1.26 ± 0.72） cm and （0.58 ±0.21） cm respectively, The differences were significant.On the normal persons, the size of the angle of SMA and AA affected the shape of the LRV. When the angle of SMA and AA was below or above 35°, the frequency of funnel-type LRV in normal persons （ the proportionality between the widest inner diameter in the left renal hilum and the most narrow inner diameter of LRV above 3） was 30.6% （15/49） and 4.7% （4/85） respectively（P〈0.05）, Conclusion 64-row spiral CT can distinctly show the angle of superior mesenteric artery （SMA）and abdominal aorta （AA） and the angle of that can affect the shape of the left renal vein （LRV）.