空间-时间相关成像技术中容积数据后处理方法的研究进展

胎儿先天性心脏病（CHD）是产前诊断的难点。空间-时间相关成像（STIC）技术是用于胎儿心脏超声诊断的三维成像技术，通过一次自动扫描，可获取胎儿心脏的容积数据，经过恰当的后处理，能获得胎儿心脏感兴趣切面图像，用于胎儿CHD筛查并辅助二维超声诊断。本文对STIC技术中容积数据后处理方法的研究进展进行综述。     

应用空间-时间成像相关技术行胎儿心脏产前筛查的可行性探讨

目的探讨空间-时间成像相关（STIC）技术在临床胎儿心脏产前筛奄应用及推广的可行性。方法对2007年11月至2008年12月在我院行超声心动图检查的心脏畸形高危胎儿214例（经二维心脏超声检查诊断为正常胎儿心脏）,尽最在无胎动时扶取有效的STIC容积数据,应用Uittenbogaard等提出的获取条件评分方法加以改良后进行STIC容积数据采集评分,最高分为10分,6分以t（含6分）为成功获得,6分以下为未成功获得。根据是否能清晰显示心脏各部分结构将所有成功获得的STIC容积信息被分为临床不可用、临床可用和临床最佳。结果根据STIC容积采集评分标准,采集的胎儿心脏容积信息评分结果为149例（69．6％）成功获得容积数据,65例（30．4％）朱成功获得;影响成功率因素中,胎动因素最常见;将研究的前半年和后半年两个时间段的成功率进行比较,后半年的成功获得率明显提高（P〈0．05）。对采集的胎儿心脏容积信息进行临床效果评价,临床效果最佳为27例（12．6％）,临床可用为139例（65．0％）,临床不吖用为48例（22．4％）;将研究的前半年和后半年两个时间段的临床价值评价结果进行比较,后半年的临床效果最伟率和临床可用牢明显提高（P〈0．05）。结论STIC技术在临床实践中获取临床最佳效果率较低,限制了其在临床上的广泛应用和推广。增加对STIC技术采集和应用的熟练程度和技巧则会明显改善信息采集的成功率和质量。     

三维超声STIC技术辅助诊断胎儿心脏畸形的研究

目的对照引产后病理检查结果比较二维超声与三维超声时间-空间相关成像技术(spatio-temporalimage correlation,STIC)判断胎儿心脏结构异常细节的准确性,探讨STIC技术对胎儿心脏畸形的产前诊断价值。方法 2006年1月～2008年10月在中山大学附属第一医院行胎儿心脏二维超声检查、可疑胎儿心脏畸形、并存储完整心脏三维超声STIC容积数据、有胎儿心脏病理检查结果的病例24例;应用4DView软件多平面重建和断层显像模式分析心脏STIC容积数据;对照引产后病理检查结果,比较二维超声和STIC技术对各类心脏结构异常的细节诊断符合率。结果心脏病理解剖显示24例中有92个心脏结构异常。二维超声和STIC技术对心脏结构异常的细节诊断总符合率分别为64.1%和97.8%;二维超声和STIC技术对房室连接异常、房室间隔异常的诊断符合率无明显差异(P0.05),而对静脉与心房连接异常、动脉与心室连接异常、动脉干及分支异常的诊断,STIC技术则优于二维超声(P0.05)。结论 STIC技术对胎儿心脏畸形中静脉与心脏连接异常、动脉与心室连接异常、动脉干及分支异常的诊断较二维超声可提供更加丰富的诊断信息,为精确诊断胎儿复杂心脏畸形提供了一个新的方法。     

空间-时间相关成像技术在胎儿心脏超声检查中的应用价值

目的：探讨应用空间-时间相关成像（STIC）技术进行胎儿心脏超声检查的可行性和临床价值。方法：应用STIC技术对30例孕龄20～34周正常胎儿进行数据采集及脱机分析和处理，对胎儿心脏各解剖结构进行显示和观察。结果：30例研究对象在获得容积数据后，通过正交三平面模式对图像进行切割平移或旋转，有26例成功获得了心脏各解剖结构，4例心脏结构未能完全显示。结论：STIC技术较传统超声心动图具有优势，具有广阔的临床应用前景。     

初学者应用超声断层成像技术显示胎儿心脏结构的探索

目的探索超声断层成像（TUI）技术能否提高初学产科超声操作医师对胎儿心脏结构的显示率,了解该技术在胎儿心脏检查中的临床应用价值。方法先由一名熟练的产科超声医师（a）应用二维超声对200例正常中孕期胎儿的心脏进行检查并存储图像;再由一名初学产科超声的医师（b）应用时空关联成像（STIC）技术获取胎儿心脏的容积数据,然后应用TUI程序获得心脏检查各切面并保存;最后由一名超声医师（c）将同一胎儿心脏的二维图像与TUI重现的心脏各切面进行对比并根据切面图像的质量及诊断价值进行评分。结果200例正常胎儿心脏超声检查中,185例获得满意的容积数据。应用TUI技术能够获得胎儿心脏检查所需的切面,获取四腔心、左心室流出道、右心室流出道、三血管及胃泡切面的显示率分别为100．O％、92．2％、87．8％、98．9％及100．0％。TUI法获取各切面与常规二维切面的显示率比较,差异无统计学意义（P〉0．05）,符合产前超声检查的质量要求。结论TUI技术是一种简单易学的胎儿心脏结构超声显示方法,初学者应用该技术能够显示胎儿心脏超声检查的常用切面,该技术降低了培训超声医师检查胎儿心脏的难度,有利于超声检查胎儿心脏的推广应用。     

时空关联成像在胎儿心脏检查中的应用研究

目的 探讨时空关联成像（STIC）技术在胎儿心脏扫查及胎儿心血管畸形诊断中的应用价值。方法 选择孕龄在19～36 周的110例正常胎儿及32例已行二维超声心动图并拟诊为先天性心血管畸形的胎儿,应用STIC技术采集心脏容积数据,部分胎儿（24例）采集四腔心切面及胸部正中矢状面容积数据,存盘后进行脱机重建研究及回顾性分析,对二维常规超声与STIC方法获得的胎儿心脏图像进行比较。结果 110例中97例正常胎儿心脏超声检查获得满意的容积数据。97例正常胎儿心脏四腔心、五腔心、左心室流出道、右心室流出道（大动脉短轴）、三血管-气管切面、上下腔静脉长轴切面的显示满意率（分别为100%、97.6%、93.8%、91.7%、92.7%、89.6%）与常规二维扫查图像的满意率（分别为100%、100%、97.9%、96.9%、95.8%、93.8%）比较差异无统计学意义,而在73例只扫查胎儿四腔心切面为基础的容积数据获得的主动脉弓长轴、动脉导管弓切面的显示满意率（分别为6.8%、19.1%、）与常规二维扫描图像显示满意率（分别为91.7%、94.5%、）比较差异有统计学意义（P<0.05）,在24例扫查胎儿四腔心切面加胸部矢状切面为基础的容积数据获得的主动脉弓长轴、动脉导管弓切面图像显示满意率（分别为91.6%、87.5%、）与常规二维扫描图像显示满意率（分别为100%、100%、）比较差异无统计学意义（P>0.05）。32例行二维超声心动图诊断为先天性心脏病胎儿,共涉及心血管畸形51处,二维筛查时漏诊1处永存左上腔,容积数据后处理分析能完全重现并诊断,并能显示更多的非标准切面。结论 STIC技术扫描胎儿心脏四腔心切面加胸部正中矢状切面为基础的容积数据能获得完整的心脏切面,能对胎儿心血管畸形二维超声心动图诊断进行补充。     

时间-空间相关成像技术评价胎儿心脏形态结构的初步研究

目的评估3D／4D时间-空间相关成像（STIC）是否能比常规二维胎儿超声心动图提供更多胎儿心脏的切面及信息。方法采用3D／4DSTIC超声系统对26例孕龄16～41周的正常胎儿进行心脏和胸部的自动扫查，获得容积数据后进行脱机分析，主要对胎儿心脏的解剖结构进行多平面的观察和三维重建，重点观察胎儿心脏的流出道等结构。结果26例胎儿皆成功获得满意二维和三维四腔心切面的图像。通过STIC技术获得的容积数据显示了一系列相互垂直的三维平面图像（即A平面、B平面、C平面），对其中的每一幅图像都可通过旋转、平移进行控制、分析。切割或三维重建图像可获得比常规二维胎儿超声心动图检查更多的切面及信息。结论3D／4DSTIC技术比常规二维胎儿超声心动图检查能更快地提供更多的观察心脏解剖结构的切面和信息。     

空间-时间相关成像技术在胎儿心脏畸形诊断中的应用

目的：探讨空间-时间相关成像技术（STIC）在胎儿心脏畸形诊断中的应用价值。方法：应用STIC技术对22例二维超声心动图发现胎儿心脏畸形的研究对象进行容积数据的采集及脱机分析和处理,观察STIC技术对各病例的显示和诊断情况。结果：22例研究对象在获得满意的容积数据后,通过图像的切割平移或旋转,不但能观察到二维扫查的各标准切面,还能显示二维超声不能显示的切面,较直观地观察病变情况。结论：STIC技术能为胎儿心脏畸形的诊断提供更多的诊断信息和依据,是二维超声心动图的有力补充。     

eSTIC技术与STIC技术显示胎儿心脏诊断切面的对比研究

目的评价电子矩阵时间-空间相关成像（eSTIC）技术显示胎儿心脏诊断切面是否较时间-空间相关成像（STIC）技术具有优势。 方法2019年1月至6月在绍兴市妇女儿童医院超声科进行产前超声检查的孕妇中，随机选择四腔心观上脊柱在5点至7点的18~24周正常胎儿64例。分别应用电子矩阵容积探头、传统机械容积探头采集同一胎儿心脏容积数据，存盘并脱机分析。应用正交三平面模式、断层超声显像模式显示胎儿心脏8个诊断切面：标准四腔心观、左心室流出道观、右心室流出道观、三血管-气管观、腹部横切观、动脉导管弓长轴观、主动脉弓长轴观、上下腔静脉-右心房观。将各个切面观重建图像的质量分为优、一般、差三级，质量为优、一般定义为合格，质量差定义为不合格。应用配对χ²检验对比2种方法显示心脏各诊断切面的合格率，应用配对秩和检验对比2种方法获得的心脏各诊断切面的成像质量的差异。 结果2种技术均采集容积数据64个，采集成功率均为100%。eSTIC、STIC对于标准四腔心观、左心室流出道观、右心室流出道观、三血管-气管观、腹部横切观的显示合格率差异均无统计学意义（P均＞0.05），但对于动脉导管弓长轴观、主动脉弓长轴观、上下腔静脉-右心房观，eSTIC显示合格率均优于STIC（均为93.8% vs 71.9%），差异均具有统计学意义（χ²均=11.925，P均=0.001）。eSTIC所有诊断切面重建图像的质量均优于STIC，差异有统计学意义（P均＜0.05）。 结论eSTIC能显著提高胎儿心脏诊断切面重建图像的成像质量。与STIC相比，eSTIC对胎儿心脏纵向诊断切面的显示更具优势。     

四维超声STIC技术检测中孕早期胎儿心脏畸形

目的探讨四维超声时空关联成像(STIC)技术筛查中孕早期胎儿先天性心脏病的临床价值。方法连续性选取70胎14～17+6周高危妊娠胎儿,先行二维超声筛查,再应用四维超声STIC技术采集胎儿心脏容积数据;由同1名超声医师采用单盲法进行分析,并将二维超声和四维超声STIC技术的诊断结果与随访结果进行比较。结果 58胎高危胎儿获得随访结果,其中心脏异常16胎,心脏正常42胎。STIC技术正确诊断率为86.21%(50/58),3胎诊断不完整,漏诊2胎,误诊3胎;二维超声正确诊断率为91.38%(53/58),1胎诊断不完整,漏诊1胎,误诊3胎;两者正确诊断率差异无统计学意义(χ2=0.78,P>0.05)。四维超声STIC联合二维超声后正确诊断率96.55%(56/58),明显高于单独应用STIC技术(χ2=3.94,P<0.05)。结论四维超声STIC技术可用于诊断中孕早期胎儿先天性心脏病;将其纳入胎儿心脏二维超声产前早期筛查,可提高正确诊断率。     

时间-空间相关成像技术在胎儿心脏超声检查中的应用

目的 探讨时间-空间相关成像(STIC)技术在正常胎儿心脏超声检查中的成像方式及其临床应用价值. 方法分别使用常规二维超声和STIC技术对120例孕龄在22～28周的正常胎儿进行心脏扫查,比较两种方法获得胎儿心脏图像的质量和扫查时间有无统计学差异,并分析STIC技术的成像方法. 结果 120例正常胎儿心脏均获得满意的容积图像,各切面图像的显示合格率与常规二维扫描图像的差异无统计学意义(P>0.05),且能显示出常规二维不能显示的切面.所研究的120例样本中,共有85例可计算常规二维超声筛查时间,平均每个胎儿心脏用时(5.26±2.01)min;共有104例可计算STIC扫描时间,平均每次STIC扫描用时(4.47±2.32)min. 结论 STIC技术比常规二维超声能提供更多的观察心脏解剖结构的切面和信息,可简化图像采集过程,缩短检查时间,减少对检查者经验的依赖,提高工作效率,同时大大减少胎儿心脏接受超声波照射的时间.     

超声容积自动测量技术联合时间空间相关成像技术在胎儿心脏检查中的应用研究

目的 利用超声容积自动测量(SonoAVC)技术和时间空间相关成像(STIC)技术研究胎儿心脏三维结构.方法 利用STIC技术采集胎儿心脏的容积数据,对有引产或生后随访结果的32例胎儿心脏利用SonoAVC回顾性分析心脏容积数据,其中20例为正常胎儿,12例为复杂先天性心脏病胎儿.系统软件SonoAVC及ROI自动搜寻无回声区或低回声区,标记为不同的颜色;再用手动描记功能修正细节.结果 心脏各房室腔及大血管能被系统识别分离,通过手动描记修正后,可得到心脏腔室及大血管的铸型图,4例大动脉转位、2例法洛四联征、1例三尖瓣下移畸形、1例右室双出口及20例正常胎儿均获得了满意的三维铸型图.结论 SonoAVC结合STIC技术能够显示胎儿心脏房室及大血管的大小、形态及三维空间关系,不仅有助于胎儿心脏畸形的诊断,而且在会诊及教学中可发挥更大的作用.

Abstract：

Objective To evaluate three dimensional fetal heart structure by sono-automatic volume count (SonoAVC) with spatio-temporal image correlation(STIC). Methods The heart volumes datas were acquired by STIC in 32 fetuses with postnatally confirmed diagnoses(20 cases of normal heart, 12 cases of complex congenital heart disease between 20 - 37 gestional weeks), then the volume datas were analyzed offline. SonoAVC software automaticly searched hypoechoic and anechoic structures, and assigned individual colors,and this can be corrected by manual splitting and/or removing and merging of individual segments.Results Individual segments of fetal heat could be separated,and digital casts were generated. The digital casts were obtained successfully in 4cases of transposition of the great arteries(TGA) ,2 cases of tetralogy of Follot,1 case of Ebstein's anomaly, 1 case of double-outlet right ventricle and 20 cases of normal heart.Conclusions Combination of STIC and SonoAVC can demonstrate the size, shape and connection of fetal cardiac cavities and great arteries in three dimensional spatial context. It has the potential both to help in obtaining strctural diagnostic,and to generate 3D visual displays for consultation and teaching.     

Four-dimensional sonography with B-flow imaging and spatiotemporal image correlation for visualization of the fetal heart

PURPOSE: To use B-flow imaging with 4-dimensional (4D) sonography and spatiotemporal image correlation (STIC) in the evaluation of normal fetal heart and congenital heart disease during pregnancy. METHOD: Volume data sets of the fetal heart were acquired with automated transverse and longitudinal sweeps of the anterior chest wall. We studied 13 normal fetuses and 2 fetuses with congenital heart disease (1 double-outlet right ventricle and 1 hypoplastic left heart syndrome) at gestation ages ranging from 13 to 39 weeks using transabdominal 4D B-flow sonography with STIC (4D BF-STIC). RESULTS: 4D BF-STIC demonstrated dynamic angiographic features in both normal and abnormal fetal hearts. 4D BF-STIC images could not be obtained in 2 normal fetuses at 18.1 and 33.1 weeks because of the high fetal heart rate and inappropriate fetal position. In normal fetal heart, characteristic hemodynamic changes in both atria and ventricles were clearly demonstrated in systole and diastole. 4D BF-STIC also allowed visualization of the relationship, size, and course of the outflow tracts, thus helping the examiner to better understand the relationships between the vessels. In a case of hypoplastic left heart syndrome, dramatic hemodynamic changes including the right atrium, right ventricle, and pulmonary artery were evident. In a case of double-outlet right ventricle with ventricular septal defect, left-to-right shunt flow through a ventricular septal defect was clearly shown, as were great arteries originating in parallel from the right ventricle. CONCLUSION: 4D BF-STIC provides a means of real-time 3-dimensional evaluation of fetal intracardiac and extracardiac hemodynamics in the second and third trimesters. This novel technique assists in the evaluation of fetal cardiac hemodynamics and may play an important role in future fetal cardiac research and in the evaluation of congenital heart disease in the fetus.     

Feasibility assessment for successfully visualizing the fetal heart utilizing spatiotemporal image correlation

Purpose

Spatiotemporal image correlation (STIC) is an excellent imaging modality for observing the fetal heart. High-quality STIC volume data are needed for an antenatal anatomic survey to diagnose congenital heart disease. We aimed to clarify the causes of unsuccessful STIC volume data acquisition and describe a more accurate, efficient STIC examination.

Methods

This cross-sectional study of 1124 women with fetuses assessed risk factors for unsuccessful acquisition of STIC volume data. Logistic regression analysis quantified the relation between unsuccessful acquisition and clinical variables, including maternal body mass index (BMI), shadowing artifacts due to unexpected fetal limb movement (SAU), estimated fetal weight (EFW), gestational age (GA), use of volume rendering images in four-dimensional ultrasonography (4D-US), fetal heart rate (FHR), maternal age, anterior placenta, and prior lower abdominal surgery.

Results

STIC volume data acquisition was unsuccessful in 210 of 1124 (18.6%) cases. SAU, BMI ≥ 28 kg/m², not using volume rendering images in 4D-US, EFW ≥ 1300 g, and anterior placenta were independent risk factors for unsuccessful STIC data acquisition.

Conclusions

Avoiding SAU was the most important factor for accurate, efficient STIC evaluations for diagnosing congenital heart disease antenatally. The risk was not explained by lack of sonographer proficiency. Volume rendering images in 4D-US is a promising approach to successful acquisition of STIC volume data.

     

时空关联成像检测胎儿复杂心脏畸形的应用价值

目的 评价时空关联成像(spatio-temporal image correlation,STIC)在诊断胎儿复杂心脏畸形中的应用价值.方法 选择二维超声筛查疑似复杂心脏畸形的25例中晚孕期胎儿,胎龄20～30周,平均(25.88±8.3)周.进行心脏和胸部的自动扫查,应用STIC技术后处理获得动态三维图像,对获得的容积数据应用正交三平面模式、表面成像模式、反转模式和最小模式离线分析进行心脏复杂畸形的诊断,并与尸解或出生后彩色多普勒超声复查的结果对照分析.结果 25例胎儿通过STIC技术均可获得满意的胎儿心脏容积数据.发现胎儿复杂心脏畸形中.右室双出口1例,永存动脉干1例,完全型大动脉转位3例,矫止型大动脉转位1例,完全性心内膜垫缺损4例,右室发育不良1例,左室发育不良2例,三尖瓣闭锁1例,肺动脉闭锁1例,法洛四联症3例,单心房1例,两腔心畸形4例,法洛五联症1例,房间隔缺损、室间隔缺损并冠状静脉窦扩张1例.23例与尸体解剖或产后复查结果相一致,敏感性为92%(23/25).结论 STIC技术能快速准确地检测出胎儿复杂心脏畸形,对妊娠预后具有重要的指导意义.     

Collaborative Study on 4‐Dimensional Echocardiography for the Diagnosis of Fetal Heart Defects

Objective. Congenital anomalies are the leading cause of infant mortality in the United States, and congenital heart defects (CHDs) are the most common type of birth defects. Recently, 4‐dimensional ultrasonography (4DUS) with spatiotemporal image correlation (STIC) has been introduced for fetal echocardiography. Accumulating evidence indicates that 4DUS with STIC may facilitate the examination of the fetal heart. Our objectives were to determine the accuracy of 4DUS for the diagnosis of CHDs and the agreement among centers. Methods. This study included 7 centers with expertise in 4D fetal echocardiography. Fetuses with and without confirmed heart defects were scanned between 18 and 26 weeks, and their volume data sets were uploaded onto a centralized file transfer protocol server. Intercenter agreement was determined using a κ statistic for multiple raters. Results. Ninety volume data sets were randomly selected for blinded analysis. Overall, the median (range) sensitivity, specificity, positive and negative predictive values, and false‐positive and ‐negative rates for the identification of fetuses with CHDs were 93% (77%–100%), 96% (84%–100%), 96% (83%–100%), 93% (79%–100%), 4.8% (2.7%–25%), and 6.8% (5%–22%), respectively. The most frequent CHDs were conotruncal anomalies (36%). There was excellent intercenter agreement (κ = 0.97). Conclusions. (1) Four‐dimensional volume data sets can be remotely acquired and accurately interpreted by different centers. (2) Among centers with technical expertise, 4DUS is an accurate and reliable method for fetal echocardiography.     

Validation of volume and mass assessments for human fetal heart imaging by 4-dimensional spatiotemporal image correlation echocardiography: in vitro balloon model experiments.

OBJECTIVE: This study was designed to validate a slow-sweep real-time 4-dimensional (4D) spatiotemporal image correlation method for producing quantitatively accurate dynamic fetal heart images using an in vitro pulsatile balloon model and apparatus. METHODS: To model fetal heart chambers, asymmetric double-walled finger stalls (tips of surgical latex gloves) were used and attached to a laboratory-designed circuit that allowed calibrated changes in the inner balloon volume as well as an intermediate gel mass interposed between the 2 layers. The water-submerged model was attached to a small-volume pulsatile pump to produce phasic changes in volume within the inner balloon at a fixed rate. A sonography system with 4D spatiotemporal image correlation (STIC) capabilities was used for 3-dimensional (3D) and 4D data acquisition. Volume data were analyzed by customized radial summation techniques with 4D data analysis software and compared with known volumes and masses. RESULTS: Fifty-six individual volumes ranging from 2.5 to 10 mL were analyzed. Volume and mass measurements with 4D STIC were highly correlated (R2 > 0.90). The mean percentage error was better (<6%) for volumes exceeding 4 mL and was as low as 0.3% for 6-mL estimations. Measurements in the diastolic phase were the most accurate, followed by mass estimations equivalent to chamber walls. There was a wider range of percentage error in the lowest volumes tested (2.5 mL), which might have arisen from difficulties in spatial resolution or distortions from within the model apparatus itself. Resolution limitations of 4D technology in combination with extremely small volume targets may explain higher error rates at these small volumes. CONCLUSIONS: Four-dimensional STIC is an acceptably accurate method for volume and mass estimations in the ranges comparable with mid- and late-gestation fetal hearts. It is particularly accurate for diastolic estimations, for chamber wall mass measurements, and at volumes of greater than 2.5 mL. This study validates use of 4D STIC technology to overcome the limitations of nongated 3D technology for phasic and quantitative assessments in fetal echocardiography.