彩色多谱勒超声在诊断小儿胡桃夹现象中应用价值

The application value of color Doppler ultrasound in diagnosis of childhood nut-cracker phenomenon

为评价彩色多谱勒超声对小儿胡桃夹现象的诊断价值 ,将随机选择的20例小儿按左肾静脉 (LRV)内径与腹主动脉和肠系膜上动脉间LRV前后径比值 (a/b)≥3和<3分为对照组A组与B组 ;与8例临床诊断胡桃夹现象的小儿进行二维及彩色多谱勒超声对比研究 ,并按简化柏努力方程计算LRV与下腔静脉的压力差 ( p) ;部分病例组患儿直立试验后重复以上检查。结果显示 ,病例组b段多谱勒测值流速(144.13±38.6)cm/s,a段流速(8.68±4.22)cm/s,与对照组比较差异明显 ,对照组A组和B组之间比较差异无显著性 ;病例组 p :(8.79±4.94)mmHg ,对照组 p<3mmHg。提示彩色多谱勒超声在诊断小儿胡桃夹现象中具有重要的应用价值 , p>

Nut_cracker phenomenon (NCP) or so_called left renal vein (LRV) compression syndrome consisted of a series clinical symptoms associated with compression of LRV between abdominal aorta (AO) and superior mesentery artery (SMA).Previously,such phenomenon has been reported for many times with 2 Dimension ultrasound(2D_echo),but in some cases,the diagnosis obtained with 2D_echo was not concordance with the clinical manifestation.So,in order to evaluate the application value of the color Doppler ultrasound in the diagnosis of children's nut_cracker phenomenon,20 cases with normal clinical manifestation selected randomly were divided into 2 control groups(control group A and control group B)according to the ratio of internal diameter of LRV proximal to the left kidney to the diameter between AO and SMA(a/b≥3,a/b<3).There were 10 cases in each group including 7 boys and 13 girls.The age distribution ranged from 5 to 12 years old,whereas 8 children with nut_cracker phenomenon were diagnosed according to the clinical manifestation including 2 boys and 6 girls.The age distribution ranged from 6 to 12 years old.Comparative study was performed with 2D_echo and color Doppler ultrasound for these three groups.The difference of the pressure(p)between LRV and inferior vena cava(IVC)was calculated with simplified Bernoullis equation.6 cases with nut_cracker phenomenon were repeated with above examination after upright test.The results showed as follows:1.All a/b ratio was ≥3 in control A and patient's group on 2D_echo,whereas the internal diameter of the a segment in patient's group was wider than that of control A.2.The velocity of blood flow at the a and b segment of LRV was 8.68±4.22 cm/s,144.13±38.6 cm/s in patient's group,obviously higher than that in control A with color Doppler ultrasound.3.There were significant difference between control group B and patient's group on 2D_echo and color Doppler ultrasound:The ratio of a/b and the velocity of the blood flow at the b segment in control group B was obviously lower than that in patient's group,whereas the velocity of blood flow at the a segment was higher than that in patient's group,Moreover,there were obvious difference in the ratio of a/b between control group A and B on 2D_echo but no significant difference on color Doppler ultrasound,and with no clinical symptoms of proteinuria,haematuria or a sore waist.In other words,there were significant difference between patient's and control groups on the velocity of blood flow at the a and b segment measured with the color Doppler ultrasound,whereas there were some difference between control group A and B on the p,but <3 mmHg,and the p was found to be greatly increased in the patient's group,with p:8.79±4.49 mmHg,all >3 mmHg.Indicating that color Doppler ultrasound had very important application value in the diagnosis of children's nut_cracker phenomenon.p>3 mmHg could be considered as a diagnostic criteria in childhood nut_cracker phenomenon.