彩色多普勒超声对儿童胡桃夹综合征的诊断价值

目的探讨彩色多普勒超声对儿童胡桃夹综合征（NCS）的诊断价值。方法选取NCS患儿（病例组）36例;选取健康体检的儿童40例,按左肾静脉（LRV）内径LRV近肾端内径（简称a段）]、腹主动脉（AO）和肠系膜上动脉（SMA）AO和SMA之间的LRV前后径（简称b段）]的LRV前后径比值（a/b比值）平均分为2组：对照A组（a/b比值≥3）和对照B组（a/b比值〈3）,每组20例。3组均行二维及彩色多普勒超声检查,按简化伯努利方程计算LRV与下腔静脉（IVC）的压力差（△P）,并行直立试验后重复以上检查。结果 3组平卧位a值、直立试验后b值比较差异无统计学意义（P〉0.05）;与对照A组、对照B组比较,病例组直立试验后a值大、平卧位b值小,平卧位及直立试验后a/b比值大、Va流速慢、Vb流速快和△P值大（P〈0.01）;病例组△P〉0.5 k Pa。对照A组平卧位b值、平卧位及直立试验后a/b比值、Va、Vb和△P值与对照B组比较差异均无统计学意义（P〉0.05）,对照A组、对照B组均△P〈0.5 k Pa。结论彩色多普勒超声对NCS具有重要的诊断价值,△P〉0.5 k Pa可作为诊断NCS的标准之一。

Value of Color Doppler Ultrasound in Diagnosis of Nut-Cracker Syndrome in Children

Objective To explore the value of color Doppler ultrasound in the diagnosis of nut-cracker syndrome in children. Methods Thirty-six patients with nut-cracker syndrome were selected as the case group. In addition, according to the ratio of internal diameter of left renal vein（LRV） proximal to the left kidney（segment a） to the diameter between aorta and superior mesenteric artery（segment b）,40 healthy children were randomly divided into control group A（a/b≥3） and control group B（a/b3）,with 20 children in each group. Two dimensional and color Doppler ultrasound were performed and the difference in the pressure（△P） between LRV and inferior vena cava（IVC）was calculated with simplified Bernoullis equation. All the above examinations were repeated after upright test. Results There were no significant differences in segment a in horizontal position and segment b after upright test among three groups（P〈0.05）. Compared with control groups, segment b after upright test, a/b ratio, Vb and △P increased and segment a in horizontal position and Va decreased in case group（P〈0.01）.The △P in case group was greater than 0.5 k Pa. No significant differences in segment b in horizontal position, a/b ratio, Va, Vb and △P were found between control group A and control group V（P〈0.05）. The △P in both control groups were less than 0.5 k Pa. Conclusion Color Doppler ultrasound has important value in the diagnosis of childhood nut-cracker syndrome, and △P〈0.5 k Pa can be considered as a diagnostic criteria for nut-cracker syndrome.