With the development and universal use of sonographic technique,prenatal ultrasonography has become an essential part of prenatal diagnosis.The doctor-patient contradicts and medial tangles occur more due to safety and limitation of prenatal ultrasonography.This article puts forward some relevant policies to resolve the doctor-patient contradicts and medial tangles via analysing relative factors and ethical problems.

Objective To investigate the relationship between preterm delivery and anterior myometrial (MA) thickness measured by ultrasound in the second trimester. Methods The general information and pregnancy outcome of singleton pregnant women who had antenatal visit in the Hunan Provincial People′s Hospital between Oct 2010 and Sep 2013 were collected prospectively. The MA thickness was measured at 20-27+6 gestational weeks. The cases were divided into preterm delivery group and term delivery group. Results (1)A total of 1 031 pregnant women were recruited in this study. 147 pregnant women were in the preterm delivery group(14.26%,147/1 031) and 884 women were in the term delivery group(85.74%,884/1 031). The gestation age at delivery of the preterm delivery group was significantly earlier than the term delivery group [(34.57 ± 2.39) vs (39.23 ± 0.92) weeks,P<0.05]. No significant difference was observed in the age, gravidity, parity, history of preterm delivery, cesarean delivery rate and gestational age at the time of MA measurement between the two groups(P>0.05). The incidence of premature rupture of membrane(PROM) in the preterm delivery group and in the term delivery group were 49.0%(72/147) and 15.8%(140/884),respectively, with statistically significant diffrence(P<0.01). (2) The mean value of MA thickness in the term delivery group was (5.49±1.39) mm, while in the preterm delivery group it was (5.60 ± 0.87) mm. There was no statistically significant difference between the two groups(P>0.05). The mean value of MA thickness in the spontaneous preterm delivery group was(5.15±0.75) mm, and was (5.61±1.38 ) mm in the term delivery group, with statistically significant difference(P<0.01). The mean value of MA thickness in the preterm premature rupture of membrane (PPROM) cases was( 5.96±0.78 ) mm, and in term delivery group with PROM it was(5.38±1.12) mm. The difference between the two groups were statistically significant (P< 0.01). (3) Among the 1 031 pregnant women, 212 women had PROM, with the mean value of MA thickness of (5.67±1.32) mm. For those who did not have PROM, the mean value of MA thickness was (5.56±1.10) mm. There was no statistically significant difference between the two groups(P>0.05). No correlation was found among PROM and MA thickness(r=0.058,P>0.05). However, in the preterm delivery group, the mean value of MA in PPROM was significantly thicker than the spontaneous preterm delivery cases(P<0.01). There was a positive correlation between the MA thickness and PPROM (r=0.457,P<0.01). Conclusion The MA thickness had some correlation with spontaneous preterm delivery and PPROM, while the MA thickness should not be considered as an independent factor of preterm delivery.

Purpose To establish myocardial infarction model in rabbits and to evaluate cardiac function and pathological changes.Materials and Methods In 35 New Zealand white rabbits, the left anterior descending branch (LAD) of the coronary artery was ligated. The cardiac function was evaluated using echocardiography, and the blood serum brain natriuretic peptide (BNP) level was examined preoperatively, on postoperative day 1, and in 1 week, 2 weeks, 4 weeks and 8 weeks for comparison. Pathological sections and HE staining were performed to observe pathological changes. Results The death rate was 28.6% (10/35). There was progressive increase in left ventricular end systolic diameter (LVESD) and left ventricular end diastolic diameter (LVEDD) at 1 week, 2 weeks and 4 weeks (P<0.05). There was progressive decrease in left ventricular ejection fraction (LVEF) and left ventricular fractional shortening fraction (LVFS) at 1 day, 1 week, 2 weeks and 4 weeks (P<0.05). The BNP level started increasing in 1 day, peaked in 1 week, then gradually decreased but remained higher than preoperative level in 8 weeks (P<0.01). Pathological section showed typical myocardial cell degeneration, necrosis, ifbrosis, calciifcation and scar formation. Conclusion This myocardial infarction model is satisfactory with signiifcant decrease of cardiac function and increase of BNP level.

Objective:To assess effect of age on the characteristic of letf ventricular (LV) twist-displacement loop in health volunteers by velocity vector imaging (VVI) and to provide a new method for LV function evaluation in clinic.
Methods:Atfer obtaining basal and apical LV short-axis images in 98 healthy volunteers (18-75 years old) by 2-dimensional echocardiography, we use VVI sotfware to analysis LV twist motion and radial displacement at each plane off-line. hTe peak LV twist (Ptw), the peak untwist velocity (PutwV), the proportion of untwist in isovolumetric relaxation period (Iutw%) and LV radial displacement (Dis) were measured and calculated. Then we constructed LV twist-displacement loop and compared the characteristic of them among different groups.
Results:Ptw increased gradually with the increase in age. The biggest PutwV was in the group of 30-60 years old. Iutw%increased gradually before 60 years old, then decreased atfer that. Dis was not obviously different among the three groups. hTe characteristic of LV twist-displacement loop was like the configuration of 8. There was a linear relation between twist and displacement during systole, and the slope increased gradually with the increase in age. During early diastole, the relatively small radial expanding displacement displayed with untwisting, resulting in a much steeper twist-displacement relationship curve occurred in each group, which was getting smooth gradually when the radial expanding displacement increased during mid to late diastole.
Conclusions:VVI can be used to effectively and noninvasively assess LV twist-displacement loop with change in age and provide important information for LV function. hTe effect of age must take into account when evaluate the LV function by the twist-displacement loop.

Objective:To explore the value of layer-specific strain technique in evaluating the changes of left ventricular myocardial systolic function in patients with aortic stenosis(AS).Methods:From January 2019 to March 2022, 90 AS patients with left ventricular ejection fraction (LVEF) ≥ 50% in Hunan Provincial People's Hospital were selected, including 30 mild AS patients, 30 moderate AS patients, and 30 severe AS patients. In addition, 30 health examinees in the same period were selected as the control group. The normal echocardiographic parameters of the control group and the AS groups with different degrees were compared. The global systolic peak longitudinal strain (GLS) and global circumferential strain (GCS) of the left ventricular three-layer myocardium were measured by the layer-specific strain technique, and the correlation between the strain parameters and the peak systolic velocity (Vmax) of the aortic valve was analyzed.Results:The levels of interventricular septal depth (IVSD), left ventricular posterior wall depth (LVPWD), mean pressure gradient (MPG), and Vmax in mild, moderate and severe AS group were higher than those in the control group (all P<0.05); the GLS of each layer of left ventricle in mild, moderate and severe AS group was lower than those in control group (all P<0.05); the GCS of each layer of left ventricle in moderate and severe AS group was lower than those in control group (all P<0.05). The GLS of left ventricular endocardium in moderate AS group was lower than those in mild AS group (all P<0.05); the GLS and GCS of left ventricular layers in severe AS group were lower than those in mild and moderate AS group (all P<0.05). In AS group, GLS and GCS in endocardium, middle layer and epicardium were negatively correlated with Vmax ( r=-0.716, -0.660, -0.669, P<0.001; r=-0.669, -0.686, -0.598, P<0.001). Conclusions:The layer-specific strain can reflect the changes of left ventricular myocardial function in patients with AS, and has certain application value.

Urethra stricture is one of the most common diseases of the urinary system. Accurate imaging diagnosis is key to the selection of surgical approach. At present, X-ray urethral imaging can show the form of urethra cavity, but not the tissues around the urethra. Sonourethrography (SUG) can dynamically identify the urethral cavity and the surrounding tissues without radiation exposure. Multi-layer spiral CT urethrography (CTU) has advantages of no need to adjust the position, quick scanning and reconstruction of the three-dimensional image, which can accurately show the location, length and degree of urethral stricture, and the spatial relationship with the surrounding tissues. Magnetic resonance urethrography (MRU) can provide useful information of the urethral stricture and soft tissues around the urethra, especially in urethral strictures caused by pelvic fractures and complex urethral stenosis. The choice of imaging method should be based on the etiology, anatomy, types of urethral injury and the general situation of patients. Appropriate imaging method can improve the diagnostic accuracy.