孕期胎儿大脑中动脉血流预测胎儿α-地中海贫血的研究

Study of Fetal Middle Cerebral Artery Blood Flow during Pregnancy to Predict Fetal Alpha Thalassemia

目的:研究胎儿大脑中动脉(MCA)血流速度与胎儿α-地中海贫血的关系。方法:选择2013年1月-2015年12月本院孕期产前检查且胎儿具有地中海贫血风险者45例,进行羊膜腔穿刺术或脐血穿刺术进行基因的诊断,行脐血穿刺者做胎儿血红蛋白(Hb)测定,并进行常规的胎儿二维及彩色多普勒超声检查及MCA-收缩期峰值血流速度(PSV)检测,Hb和MCA-PSV均用中位数的倍数(MOM)表示。结果:与正常胎儿比较,α-地中海贫血胎儿的MCA-PSV异常升高,差异有统计学意义(P<0.05),重型α-地中海贫血胎儿的MCA-PSV值高于中型与轻型,但差异均无统计学意义(P>0.05)。MCA-PSV随孕周增加而递增,两者有正相关性(r=0.9733,P<0.05),对二者进行相关性回归分析,MCA-PSV为因变量(a),孕周为自变量(b),结果显示,两者成线性关系,即:a=1.986b+10.217(a单位为cm/s,b单位为周)。MCA-PSV预测α-地中海贫血的灵敏性与特异性分别为84.8%和89.7%。对于产前及引产后确诊的α-地中海贫血有29例,其中MCA-PSV异常有15例,阳性率为51.7%(15/29);5例为胎儿血红蛋白H病,MCA-PSV异常有1例,阳性率为20.0%(1/5)。结论:MCA收缩峰期血流速度(PSV)对胎儿α-地中海贫血的预测及诊断具有重要的参考价值。

Objective： To study the relationship between fetal middle cerebral artery （ MCA ） blood flow velocity and fetal alpha thalassemia.Method： 45 fetuses in our hospital for prenatal examination and the risk of thalassemia from January 2013 to December 2015, gene diagnosis of amniocentesis or umbilical cord puncture for umbilical cord puncture do fetal hemoglobin （ Hb ） were measured, and the conventional two-dimensional fetal echocardiography and color Doppler and MCA-peak systolic velocity （ PSV ） detection, both Hb and MCA-PSV were expressed as median multiples （MOM） .Result： Compared with the normal children, the MCA-PSV of the fetus with thalassemia in α-increased, the difference was statistically significant （ P〈0.05 ）, the MCA-PSV value of severe α-thalassemia fetus was higher than that of medium and light, but the differences were not statistically significant （ P〉0.05 ） .MCA-PSV increased with gestational weeks, and there was a positive correlation （ r=0.9733, P〈0.05 ）, correlation regression was analyzed, MCA-PSV as dependent variable （ a ）, gestational weeks as independent variables （ b ）, the results show that the two are linear, that is： a= 1.986b＋ 10.217 （ a units of cm/s, B units for weeks ） .The sensitivity and specificity of MCA-PSV in prediction of hemoglobin were 84.8% and 89.7%, respectively.There were 29 cases of mediterranean anemia diagnosed before and after induction of labor, including 15 cases of MCA-PSV abnormalities, positive rate of 51.7% （ 15/29 ） ; 5 cases of fetal hemoglobin, MCA-PSV abnormalities in 1 case, the positive rate of 20.0% （ 1/5 ） .Conclusion： MCA peak systolic blood flow velocity （ PSV ） has important reference value for the prediction and diagnosis of fetal alpha thalassemia.