Study And Application Of Four-dimensional HD-flow Technique In Imaging Anatomy Of Fetal Venous Dysplasia Above The Heart

Background and purposeAt present,the malformation of cardiovascular system is still the main cause of infant mortality from congenital defects.The Imaging techniques for clinical diagnosis of congenital heart disease mainly include two-dimensional ultrasound diagnosis,ultrasonic microvesicular Imaging,CT(Computed Tomography)diagnosis,multi-slicespiral CT(MSCT)and MRI(Magnetic Resonance Imaging).Multi-slice spiral CT(MSCT)has been used to evaluate the development of pulmonary arteries and veins instead of digital subtraction pulmonary angiography due to its high sensitivity and non-invasive nature.Noninvasive angiography(CTA)has become an important noninvasive method for the diagnosis of cardiac and vascular malformations.Although the above methods can be used to diagnose vascular diseases,they require low doses of radiation and contrast injections,which are strictly prohibited in the examination of pregnant women and therefore cannot be used in prenatal diagnosis.Although MRI does not have any radiation and can be used at any time,this technique is expensive and has poor reproducibility,so it is not used routinely to diagnose fetal and newborn heart diseases.Compared with the above methods,the two-dimensional ultrasonic diagnosis technology has the advantages of non-invasive,high convenience,no radioactive damage,low price and high repeatability,and is still in the leading position in the clinical diagnosis of congenital heart disease.However,in prenatal diagnosis,the results of two-dimensional ultrasound diagnosis are easily affected by the pregnant woman's abdominal wall,fetal position and sheep water volume,etc.,in addition,the operator's own techniques and experience will also reduce the accuracy,which is easy to cause misdiagnosis and missed diagnosis.High definition blood flow imaging(High definition blood flow imaging)can accurately evaluate fetal hemodynamics,low blood flow display such as pulmonary veins and other vascular structures,imaging effect is better than color doppler blood flow imaging.Pulmonary veins can be precisely positioned in the HD-flow,and HD blood flow can show the main blood vessels circulating throughout the fetus and show the spatial relationship of blood vessels.Therefore,this technique has the advantage that other techniques lack in diagnosing abnormal development of fetal cardiovascular system.This study focuses on the fetus of superior vena cava and pulmonary vein anatomy abnormality diagnosis,using two-dimensional regular prenatal screening and 4 d ultrasound HD-flow technology,compared with single prenatal two-dimensional ultrasound routine screening,to explore a more effective prenatal diagnosis technology,for clinical fetal cardiovascular system especially large vascular abnormalities,such as the provision of more reliable treatment of references,the fetal antenatal is to get more rigorous assessment,for children to be able to get the best treatment plan and timing to provide relatively reliable basis for imaging.1.Materials and methodsA total of 1032 pregnant women who came to our hospital for routine systematic color doppler ultrasound screening from January 2016 to December 2019 were selected as research objects.The gestational ages were 24-26 weeks and 28-32 weeks.The pregnant women were 23-38 years old,and the fetuses were all single living fetuses.The pregnant women had no gestational complications such as gestational diabetes mellitus,gestational hypertension,congenital heart disease and family history of genetic diseases.No drug history before and after pregnancy,no pregnancy history,no animal contact history,living environment without any pollutants.Pregnant women over 35years old(including 35 years old)had chromosome examination,and no abnormality was found.2.Ultrasonic diagnostic instrumentThe E8 model color doppler ultrasound diagnostic instrument produced by GE has a low frequency probe with a frequency of 2-5MHz and a power of less than100mw/cm~2.The detection time of color doppler and spectrum doppler was less than5min.Abdominal-type four dimensional volume probe,frequency is 4-8MHz,and equipped with video and playback functions.3.Diagnostic methodsPregnant women were selected to supine position,and two-dimensional conventional examination conditions were first selected on the ultrasonic diagnostic instrument to evaluate the fetal growth and development.Then switch to the fetal two-dimensional ultrasound cardiac examination condition,the fetal heart for detailed observation and data acquisition.After all examinations,ultrasonic HD-flow condition was selected on the four-dimensional ultrasound diagnostic instrument,and the four-dimensional probe was used to image the upper vein of the fetal heart,mainly including the image acquisition of pulmonary vein and superior vena cava.HD-flow technology was adopted to combine two-dimensional ultrasound diagnosis technology with simple two-dimensional ultrasound diagnosis technology,and two kinds of examination were compared according to the number of veins displayed and the same pregnant woman.SPSS 17.0 statistical software was used for statistical analysis.4.ResultsTo select 1032 cases of pregnant women,through two-dimensional ultrasonography combined with two-dimensional ultrasound HD-flow technology compared with two kinds of screening methods,two-dimensional ultrasonography combined with HD-flow technology on display superior vena cava and pulmonary vein anatomy has obvious advantages,two methods for screening out of disease,can be found in the two-dimensional ultrasound has missed diagnosis and misdiagnosis,simple two-dimensional ultrasound screening for 7 cases of misdiagnosis;Combined with hd-flow technology,8 cases were diagnosed with leakage disease.5.ConclusionConventional ultrasound screening combined with HD-flow imaging technology can better display the connection between superior vena cava and pulmonary vein in detail,the disease diagnosis rate has been improved,the rate of missed diagnosis and misdiagnosis has been significantly reduced,providing more accurate and reliable reference for clinical treatment,thus improving the quality of life of children.