Retrospective Analysis Of Prenatal Ultresound Screening For Fetal Anatomy Structural Abnormalities

Objective To investigate the value of prenatal ultrasound on screening for fetal structural anatomies and analysis of the causes of missed diagnosis and misdiagnosis of fetal malformations.Methods1.From March 2014 to March 2017,7160 pregnant women as the studying objects were screened by the systematic prenatal ultrasound examination.Through the ultrasound examination in different gestational age,record the gestational age,types and numbers of the correct diagnosis of fetal malformations and classify them according to the systematic anatomy.Calculate the proportion of fetal malformations of different gestational age and calculate the sensitivity,specificity,positive predictive value,negative predictive value,positive likelihood ratio,and negative likelihood ratio.2.In 7160 cases of pregnant women,analyze ultrasound diagnosis of fatal malformations with high risk factors,the results were compared by chi squared test between high risk factors and no high risk factors.3.In 7160 cases of pregnant women,the results of ultrasonic diagnosis were compared with the results of labor induction and clinical delivery.The results were analyzed by chi square test.According to the anatomical structure of the system,fetal malformations were classified,Results1.In this group,264 cases of fetal structural abnormalities were correctly detected,the detectable rate was 3.69%.According to the anatomical structure of the system,fetal malformations of the top 5 were cardiovascular system,central nervous system,urinary system,facial and neck abnormalities,skeletal muscle system and anterior abdominal wall deformity tied for fifth.According to the disease type,the top 5 were cleft lip and palate,anencephaly and exencephaly,polycystic kidney,hydrocephalus,endocardial cushion defect and hydronephrosis tied for fifth.2.Screening out malformations in the early pregnancy and early second trimester was the central nervous system(anencephaly and exencephaly).The deformities covered all systems in the second trimester,and the most common deformities were the cardiovascular system,followed by urinary tract and neural tube defects.The late pregnancy was given priority to with cardiovascular malformation,followed by facial and neck deformity and urinary tract abnormalities.3.Prenat al ultrasound diagnosis coincidence rate was 99.59%,the sensitivity was91.35%,the specificity was 99.94%,positive predictive value was 97.78%,negative predictive value was 99.67%,positive likelihood ratio was 1552.5,negative likelihood ratio was 0.0865.4.The incidence of fetal malformation was significantly correlated with the infection of pregnant women,the advanced age,the exposure to harmful substances during pregnancy and the use of drugs that can cause malformations.5.Through the follow-up of ultrasonic missed diagnosis and misdiagnosis results: 23 cases of missed diagnosis,6 cases of misdiagnosis,of which 2 cases of cardiac malformations were error diagnosis,of which 4 cases of normal fetal were diagnosed as slight deformities.The results of ultrasound diagnosis were compared with the results of labor induction or clinical delivery,P>0.05.This indicated the ultrasonic diagnosis of error diagnosis was existed,but prenatal ultrasound in the diagnosis of fetal malformation is still of great significance.Conclusion The prenatal systematic ultrasound screening for fetal abnormal anatomy is very important,although sonography can not screen out all the diseases,but its safety performance,repeatability,non-invasive and so on make ultrasound has become an essential examination method in obstetrics department.