Research On The Application Of Spatio-temporal Image Correlation Technology In The Screening Of The Fetal Heart In Second-trimester Pregnancy

PART ONEObjective To research on the application of the spatio-temporal image correlation(STIC) in the fetal heart screening, analyze the optimal conditions of the fetalcardiac structure screening applying STIC and the impact factors to the successfulcollection, and quest for the methods to process the ultimate picture quickly.Methods150normal Second-trimester fetuses screened by routine ultrasonicscreening. To obtain the data of the volume in the fetal cardiac cycle by scanningthe fetal heart from the four-chamber view with STIC, reconstruct five types ofcommonly-used plans of LVOT、RVOT、LAV-AOA、LAV-DA、3VT with ‘A PlaneRotation Method’ of STIC, divide the plans into apical four-chamber group andlateral four-chamber group according to the acquisition position, and compare theplan reconstruction ratio of above two groups applied with χ~2test, then t testanalyze the impact factors in data collection, such as the maximum depth ofamniotic fluid, fetal gestational age, fetal weight, fetal heart rate, placenta position(χ~2test) etc. Result Among the150cases in Second-trimester fetuses screened with STIC,123(82%) cases succeeded,27(18%) cases failed. Each condition’s effect tosuccess ratio of data collection has no significant difference (P>0.05). The STICreconstruction rate of apical four-chamber group and the lateral four-chambergroup has no significant difference (χ2=0.624, P=0.891).Conclusion When the fetuses are still, applying STIC in the fetal heart screeningcan obtain satisfactory data of fetal heart volume with less other impact factors. Atthe same time, applying orthogonal planes methods of STIC in the ultimatepicture processing can obtain image of satisfactory quality. So STIC possessesimportant clinical value and can be widely used in the Second-trimester fetal heartexamination. PART TWOObjective To assess the application of the STIC in Second-trimester fetal cardiacfunction.Methods Fetal heart ventricular volumes were measured using STIC in110normal Second-trimester fetuses. Then, we analyzed the data with virtual organcomputer-aided analysis method and drew the volumes of each ventricular inend-systole （EDV） and end-diastole (ESV), calculated the stroke volume (SV)of the left and right ventricle，cardiac output (CO) and ejection fraction (EF),evaluated the correlation of SV, CO, EF with gestational age.Result Among the110normal fetuses,94(85.5%) fetuses’ ventricular volumeswere satisfactory. Mean left and right stroke volumes (SV) and cardiac output （CO）increased from（0.33±0.06）ml and（0.40±0.07）ml,(49.66±8.10)ml/minand (59.96±9.43)ml/min at20weeks, to（1.13±0.11）ml and(1.29±0.11)ml,(163.51±17.68)ml/min and (187.57±15.98)ml/min at27+6weeks, respectively.Mean LVEF and RVEF is (49.48±4.12)%and (51.07±4.00)%respectively. Theleft and right stroke volumes (SV) and cardiac output (CO) increased withgestation age and r-values were both positive(r=0.9，P＜0.05). The left and rightEF had no evident relativity with gestation age(r=0.02、0.04， P＞0.05).Conclusion STIC technique can measure fetal ventricular volumes and evaluatefetal cardiac function exactly and impersonally, has the potential to become a newmethod of choice to check the fetal cardiac function.