三维超声在产后压力性尿失禁诊断中的应用价值

目的:探讨产后压力性尿失禁(SUI)妇女盆膈裂孔的大小及耻骨内脏肌的厚度。方法:对43例产后SUI妇女行经会阴三维超声检查,并与48例无SUI症状的产妇作对照观察。测量两组产妇在静息、张力(Vasalva动作)和缩肛动作时的盆膈裂孔前后径、横径、面积及耻骨内脏肌厚度。结果:在静息、张力及缩肛动作3种状态下,SUI组盆隔裂孔前后径、面积均明显大于对照组(P<0.05或P<0.01);在张力状态时,SUI组盆膈裂孔横径明显大于对照组(P<0.05),在张力状态及缩肛动作时,SUI组耻骨内脏肌厚度均明显小于对照组(P<0.05)。结论:产后SUI患者盆膈裂孔增大,耻骨内脏肌厚度减小。经会阴三维超声是对产后SUI患者进行诊断的有效影像学检查方法。

三维超声诊断胎儿唇腭裂畸形20例报告

资料与方法 1研究对象选择我院2007~2010年孕16~28周孕妇10800例,年龄19~45岁,平均孕周23周。2仪器与方法采用GE Voluson 730 Expert彩色超声诊断仪,配备RAB2-5L容积探头,频率2~5MHz。

经阴道三维超声、断层超声显像技术诊断早期异位妊娠临床研究

目的:探讨早期异位妊娠采用经阴道三维超声联合断层超声显像技术诊断的准确性。方法:选择停经4~6周的130例疑似异位妊娠患者,所有患者均接受腹部三维超声检查、阴道三维超声检查、断层超声显像检查,分析腹部超声、阴道三维超声、断层超声显像的声像图。以手术病理及临床随访结果作为确诊标准,计算腹部超声、阴道三维超声、断层超声显像对早期异位妊娠的诊断灵敏度、特异度、准确性,并比较腹部超声、阴道三维超声、断层超声显像对不同类型异位妊娠的诊断符合率。采用Kappa一致性检验,分析腹部超声、阴道三维超声、断层超声显像诊断结果与手术病理及临床随访结果之间的一致性。结果:断层超声显像、阴道三维超声的诊断灵敏度、特异度、准确性均高于腹部超声诊断结果(P<0.05),而断层超声显像与阴道三维超声的诊断灵敏度、特异度、准确性比较差异均无统计学意义(P>0.05)。经Kappa一致性检验分析,腹部超声、阴道三维超声、断层超声显像诊断结果与手术病理及临床随访结果之间的一致性Kappa值分别为0.514、0.723、0.748。断层超声显像、阴道三维超声对输卵管妊娠、剖宫产后瘢痕妊娠的诊断符合率均高于腹部超声(P<0.05),而断层超声显像与阴道三维超声的诊断符合率比较差异无统计学意义(P>0.05)。结论:在早期异位妊娠诊断中,采用断层超声显像、阴道三维超声均具有显著的诊断价值,临床上可采取断层超声显像与阴道三维超声联合诊断,以进一步提高其诊断准确性。

动态三维超声STIC技术对胎儿心内膜垫缺损的诊断价值

目的:探讨动态三维超声STIC技术对胎儿心内膜垫缺损的诊断价值。方法:使用GE Voluson 730彩色超声诊断仪对1800例高危孕妇进行检查,其中26例经二维超声心动图诊断为心内膜垫缺损,再应用动态三维超声STIC技术进行容积数据重建研究并脱机回顾性分析,后与尸检或生后超声心动图结果进行比较。结果:动态三维超声STIC技术与常规超声在诊断胎儿心内膜垫缺损中的准确率分别为92.42%、89.63%,二者比较差异无统计学意义(P>0.05)。动态三维超声检查时间短于常规超声,差异有统计学意义(P<0.005)。结论:动态三维超声STIC技术较常规胎儿超声心动图可获得更多的切面,可在较短时间内准确、直观显示胎儿心内膜垫缺损,是能准确、简便地诊断胎儿期胎儿心内膜垫缺损的一种新方法。

Model and optimization of ultrasonic phased array parameters

Beam focusing is one of the unique characteristics of ultrasonic phased array compared with conventional ultrasound.On the basis of two-dimensional radiated sound field of phased array,the three-dimensional radiated sound field was simulated in the paper,and then the effect of different frequencies,different number of array elements and different element spacings on focal spot,the depth of focus and the effect on horizontal and vertical resolution were analyzed.The optimal results of transducer parameters have certain reference value for the design of phased array probe.

Contrast-enhanced 3D ultrasound in the radiofrequency ablation of liver tumors

Liver metastases and hepatocellular carcinomas are two of the most common causes of cancer deaths in the world.Radiofrequency ablation(RFA) is a well recognized,effective and minimally invasive means of treating malignant hepatic tumors.This article describes the use of contrast-enhanced 3D ultrasound(CE-3DUS) in the staging,targeting and follow-up of patients with liver tumors undergoing RFA.In particular,its value in the management of large hepatic lesions will be illustrated.Current limitations of CE-3DUS and future developments in the technique will also be discussed.In summary,CE-3DUS is useful in the RFA of liver tumors with improved detection and display of occult lesions and recurrence,in the assessment of lesional geometry and orientation for a more accurate planning and guidance of multiple RFA needle electrodes in large tumors and in the evaluation of residual or recurrent disease within the immediate and/or subsequent follow-up periods.

Double contrast-enhanced two-dimensional and three-dimensional ultrasonography for evaluation of gastric lesions

AIM： To investigate the value of two-dimensional （2D） and three-dimensional （3D） double contrast-enhanced ultrasonography （DCUS） imaging for evaluation of gas- tric lesions. METHODS： 2D and 3D DCUS imaging with both oral and intravenous administrations of contrast agents was used to assess gastroscopiclly-confirmed gastric lesions in 46 patients with benign and malignant diseases. Initially, liquid-based ultrasound contrast agent （Xinzhang） was given orally at dose of 500-600 mL for conventional ultrasound examination of the gastric lesions, and then a microbubble-based contrast agent （SonoVue） was injected intravenously at dose of 1.2-2.4 mL in bolus fashion to assess the perfusion pattern of the lesions using contrast imaging modes. The parameters derived from time-intensity curves including the arrival time （AT）, time to peak （lq-P）, peak intensity （PI） and en- hanced intensity （EI） were measured on the 2D DCUS imaging. 3D DCUS of the lesions was acquired to dem- onstrate the value of this imaging mode. RESULTS： There were 22 cases with benign lesions including chronic gastritis （n= 5）, gastric ulcer （n = 9）, gastric polyps （n = 3）, gastric stromal tumors （n = 5）, and 24 cases with malignant lesions including gastric cancer （n = 20）, gastric cardia carcinoma （n = 3） and post-operative recurrent gastric cancer （n = 1） in the study, The oral contrast-enhanced ultrasonography （CEUS） imaging of the stomach clearly demonstrated the anatomy of the stomach and morphologic features of gastric lesions, With optimal scanning window and imaging display under oral CEUS, intravenous CEUS clearly showed the perfusion of gastric lesions with various characteristic manifestations. Both 2D and 3D DCUS images clearly demonstrated normal gastric wall as a three-layer structure, from the inside out, hypere- choic mucosa, hypoechoic muscularis and hyperechoic serosa, respectively. There were statistical significant differences of AT （8.68±2.06 vs 10.43 ±2.75, P = 0.017）, PI （34.64 ± 6.63 vs 29.58 ± 8.22, P = 0.023） and EI （29.72 ± 6.69 vs 22.66 ± 7.01, P = 0.001） between malignant lesions and normal gastric wall. However, no differences of AT, PI and EI between benign lesions and normal gastric wall tissue were found. 3D DCUS could intuitively display morphological features and vascularities of the lesions with multiplanar and volume views. 3D DCUS imaging provided comprehen- sive information complementary to 2D imaging. The crater or wellhead appearances and feeding vessels as well as distorted nourishing vasculature of gastric carcinoma were better seen with 3D imaging than 2D imaging. CONCLUSION： DCUS imaging can simultaneouslydisplay the anatomic and perfusion features of gastric lesions. 3D DCUS can provide additional information to 2D DCUS for evaluation of gastric lesions.

REAL-TIME THREE-DIMENSIONAL ECHOCARDIOGRAPHY FOR QUANTIFYING LEFT VENTRICULAR MASS

To test the accuracy of real-time three-dimensional echocardiography (RT3DE) imaging system for evaluating left ventricular mass (LVM) in phantom and excised canine heart. Methods Ten left ventricular (LV) wall phantoms made of two rubber-bursas, ten excised canine hearts underwent RT3DE and two-dimensional echocardiography (2DE). In RT3DE "full volume" imaging, the myocardial volume was mea-sured using 2,4,8, and 16-plane method with the analysis software of RT3DE. Mass was then calculated by multiplying the resulting myocardial volume by specific density of myocardial tissue. In 2DE the masses were measured by area-length meth-od. The true LV wall phantom mass was measured by water displacement and the canine LVM was weighed by anatomy, which served as a reference standard. We compared RT3DE or 2DE with true mass. Results In LV wall phantoms, RT3DE correlated with true masses strongly (r = 0.813-0.994) and weakly correlated between 2DE and true masses (r = 0.628). In excised canine hearts, there is an excellent correlation between RT3DE and true masses (r = 0.764-0.991), while 2DE value showed a lesser correlation (r = 0.514). There are no difference between RT-3DE and true masses (P > 0.05) but different between 2DE and true masses (P < 0.05). In different planes, there was no difference between 8-plane and 16-plane (P > 0.05) but different between 8-plane and 2, 4-plane (P < 0.05). Conclusion RT3DE can accurately quantify LVM and provide a new tool to evaluate LV function. For LVM by RT3DE, 8-plane measurement method is the best choice for accuracy and convenience.

Role of three-dimensional endoanal ultrasound in assessing the anal sphincter morphology of female patients with chronic proctalgia

AIM To assess the role of three-dimensional endoanal ultrasound (3D-EAUS) for morphological assessment of the anal sphincter of female patients with chronic proctalgia (CP). METHODS In this unmatched case control study, 30 consecutive female patients with CP and 25 normal women (control group) were enrolled. 3D-EAUS was performed in all subjects. Thickness and length of internal anal sphincter (IAS), thickness of puborectalis muscle (PR), length of the external anal sphincter (EAS) plus PR, and puborectalis angle were measured and compared between the two groups. RESULTS Patients with CP had significantly shorter IAS length and greater PR thickness, as compared to those in normal individuals (26.28 +/- 3.59 mm vs 28.87 +/- 4.84 mm, P < 0.05 and 9.67 +/- 1.57 mm vs 8.85 +/- 0.97 mm, P < 0.05, respectively). No significant between-group differences were observed with respect to IAS thickness and the EAS plus PR length (P > 0.05). Puborectalis angle in the CP group was significantly decreased, both in resting (88.23 degrees +/- 1.81 degrees vs 89.94 degrees +/- 2.07 degrees in control group, P < 0.05) and straining (88.47 degrees +/- 3.32 degrees vs 90.72 degrees +/- 1.87 degrees in control group, P < 0.05) phases, which suggest the presence of paradoxical contraction of PR in patients with CP. In the CP group, no significant difference in puborectalis angle was observed between the resting and straining phases (88.23 degrees +/- 1.81 degrees vs 88.47 degrees +/- 3.32 degrees respectively, P > 0.05). CONCLUSION The association of greater PR thickness and paradoxical contraction of PR with CP suggest their potential value as markers of CP.

Three-dimensional endoanal ultrasonographic assessment of an anal fistula with and without H_2O_2 enhancement

AIM： To evaluate the effectiveness of three-dimensional endoanal ultrasound （3D-EAUS） in the assessment of anal fistulae with and without H202 enhancement. METHODS： Sixty-one patients （37 males, aged 17-74 years） with anal fistulae, which were not simple low types, were evaluated by physical examination and 3D-EAUS with and without enhancement. Fistula classification was determined with each modality and compared to operative findings as the reference standard. RESULTS： The accuracy of 3D-EAUS was significantly higher than that of physical examination in detecting the primary tract （84.4% vs 68.7%, P = 0.037） and secondary extension （81.8% vs 62.1%, P = 0.01） and localizing the internal opening （84.2% vs 59.7%, P = 0.004）. A contrast study with H202 detected several more fistula components including two primary suprasphincteric fistula tracks and one supralevator secondary extension, which were not detected on non-contrast study. However, there was no significant difference in accuracy between 3D-EAUS and H202- enhanced 3D-EAUS with respect to classification of the primary tract （84.4% vs 89.1%, P = 0.435） or secondary extension （81.8% vs 86.4%, P = 0.435） or localization of the internal opening （84.2% vs 89.5%, P = 0.406）. CONCLUSION： 3D-EAUS was highly reliable in the diagnosis of an anal fistula. H2O2 enhancement was helpful at times and selective use in difficult cases may be economical and reliable.

OMNIPLANE TRANSESOPHAGEAL ECHOCARDIOGRAPHY IMAGING PLANES EXPLORATION

One hundred and twenty-four patients with heart disease were examined by omniplane TEE in order to systematically research every views of omniplane TEE, and further explore anatomy and image feature of each view. The result showed that omniplane TEE transducer can be rotated in probe from 0°to 180°.obtain many views at various angles behind the heart and fully demonstrate the structure and pathology of the heart and great vessels. It was useful for clinical diagnosis because of getting more information about the heart and great vessels. As omniplane TEE probe was little rotated in esophagus, it lessened esophagus stimulation. Meanwhile, it was suitable for three-dimensional reconstruction of left ventriculum.

Effects of Ultrasound on the Weld Bead Surface of High Carbon Steel Sheets

Power ultrasound is finding widespread applications in assisting conventional processes yielding products of better quality at lower processing power and temperature. Transmission of ultrasound is known to be affected by the boundaries between layers of different materials or same material but in different states （solid or liquid or gas）. This paper investigates the effects of ultrasound （US） on the surface of the solidified weld which has been subjected to ultrasonic vibrations of 20 kHz frequency during laser welding. Vibrations due to ultrasound normally exert a very high force which is usually hundred or thousand times the gravity. The transverse waves will also cause movement of molten material in the weld. As the surface of the weld beads were of interest and not the mechanical properties and the microstructure, investigation of bead on plate welds were found to be sufficient. High carbon steel plate was held at one end by the ultrasonic horn through which ultrasound was injected. A bead on plate weld using a CO2 laser （1 kW） was then performed along the center of the plate using three different welding speeds namely, 400, 1200 and 2000 mm per minute. The ultrasonic powers selected were 3 W and 6 W respectively for each welding speed as higher acoustical power was causing ejection of molten metal from the pool during welding. 3D surface measurements and analysis were then made on a section of length 20 mm using a Talysurf machine. The results show that the surface of the weld was affected to different extent depending on the positions being considered in the weld. Some regions were similar to the reference weld whereas some specific regions were heavily disrupted with deep valleys followed by high peak/s. This shows that US vibration of weld pools, even at very small acoustical power, is a more complex problem than other similar processes such as casting because of the very small volume of molten metal involved.

A k-ε Turbulence Model Considering Compressibility in Three-Dimensional Transonic Turbulent Flow Calculation

Based on the standard k-ε turbulence model, a new compressible k-ε model considering the pressure expansion influence due to the compressibility of fluid is developed and applied to the simulation of 3D transonic turbulent flows in a nozzle and a cascade. The Reynolds avenged N-S equations in generalized curvilinear coordinates are solved with implementation of the new model. The high resolution TVD scheme is used to discretize the convective terms. The numerical results show that the compressible k-ε model behaves well in the simulation of transonic internal turbulent flows.

Assessment of Levator Hiatus by 3D Ultrasound Volume Contrast Imaging in Normal Nulliparas

The ability of 3D ultrasound volume contrast imaging in C-plane （VCI-C） in the assessment of female levator hiatus was analyzed in eighty normal nullipaxas. Interoperator variability in levator hiatus measurements was analyzed. The comparison of the axial image of magnetic resonance imaging （MRI） and C-plane image of volume contrast imaging （VCI） in thirty normal nulliparas was also done. It shows that VCI-C can clearly demonstrate the structure and accurately quantitates the size of the levator hiatus. It is reliable, convenient and without contraindication in assessment of female levator hiatus. The technology opens up entirely new modality for assessing female pelvic floor.

Accuracy of three-dimensional quantification of left ventricular function using magnetic sensor acquisition: a dynamic in vitro model

Objective To evaluate the accuracy of a three-dimensional (3D) magnetic position sensor system in the quantification of ventricular stroke volumes in a dynamic model.Methods A latex balloon model of the left ventricle was suspended in a water bath connected to a pump producing 10 different pulsatile stroke volumes (15-65mi/beat). Scanning was performed using a 5.0 mHz transducer mounted with a Flock of Birds (FOB) magnetic receiver (GE System Five). The probe was scanned to sweep continuously across and over the balloon volume over 3 - 7 seconds. Digital loops were stored on magneto-optical disks and reviewed retrospectively using 3D Echopac software (GE)based on Simpson's method and compared with a two-dimensional (2D) biplane area-length method (1/2L x R) measurements at end systole and end diastole. Both 3D and 2D derived stroke volumes were compared with the reference stroke volume calculated by direct measurement of balloon capacity.Results There was an improved correlation between 3D stroke volume and reference stroke volume ( y = 0.91 x + 0.41, r = 0.97, SEE = 2.83 ml, P = 0.0001 ) compared to 2D stroke volume and reference stroke volume (y=0.49x+8.68, r=0.87, SEE=3.87 ml, P=0.0011, difference between 2D and 3D P＜0.003).Conclusion 3D magnetic FOB scanning is practical, accurate and should facilitate assessment of left ventricular function.

Delamination damage detection of laminated composite beams using air-coupled ultrasonic transducers

Air-coupled ultrasonic transducers are used to generate and receive Lamb waves in quasi-isotropic laminated composite beams for delamination detection. The influence of incident angle on the excited mode is studied. Numerical calculation and experimental results show that a pure Lamb wave mode can be generated if the transmitting transducer is oriented at a specific angle, and the receiving transducer can either be oriented to detect the same mode as that generated by the transmitter or to detect another mode generated by mode conversion at a defect. A three-dimensional finite element model is created to predict the interaction of Lamb waves with delamination, and some unique mechanisms of interaction between A0 mode Lamb waves and delamination are revealed in detail. The experimental results obtained on laminated composite beam using air-coupled ultrasonic transducers are well in accordance with finite element simulation results. Research results show that air-coupled ultrasonic guided waves can be used for delamination damage detection effectively in laminated composite beams.

Three-dimensional nonlinear coupling guidance for hypersonic vehicle in dive phase

Three-dimensional(3D)nonlinear diving guidance strategy considering the coupling between longitudinal and lateral motions for hypersonic vehicle is investigated in this paper.It constructs the complete nonlinear coupling motion equation without any approximations based on diving relative motion relationship directly,and converts it into linear state space equation with the same relative degree by feedback linearization.With the linear equation,slide mode control with strong robustness is employed to design the guidance law,and 3D diving guidance law which can satisfy terminal impact point and falling angle constraints with high precision is obtained by substituting the previous control law into the origin nonlinear guidance system.Besides,regarding lateral overload as the standard,hybrid control strategy which can take full advantage of the excellent characters of both bank-to-turn(BTT)and skid-to-turn(STT)controls is designed to improve the guidance accuracy further.Finally,the results of CAV-H vehicle guidance test show that the algorithm can realize high accuracy guidance even if serious motion coupling exists,and has strong robustness to the path disturbances and navigation errors as well.