应用时间-空间关联成像技术评价正常胎儿房室瓣

Application of spatio-temporal image correlation in evaluation on normal fetal atrioventricular valve

目的评价应用三维超声时间-空间关联成像(STIC)技术观察胎儿房室瓣结构、测量正常胎儿房室瓣的周长和面积、观察其随孕周的变化的可行性。方法利用STIC技术采集176胎胎龄20～32周正常胎儿的心脏容积数据,在不同成像模式下观察胎儿房室瓣立体形态,手动测量房室瓣环的周长和面积,分析所得数值与孕周的关系。结果①176胎中,144胎应用STIC技术观测房室瓣成功,成功率为81.82%(144/176)。二、三尖瓣的周长和面积与孕周呈正相关。从20周到32周,二尖瓣平均周长从(2.41±0.35)cm增至(3.49±0.25)cm,平均面积从(0.36±0.14)cm2增至(0.97±0.23)cm2;三尖瓣平均周长从(2.46±0.23)cm增至(3.56±0.21)cm,平均面积从(0.34±0.10)cm2增至(0.96±0.23)cm2。②与二维超声相比,STIC技术可以更好地显示房室瓣结构,瓣叶在各种模式下均可得到较好显示,瓣环、乳头肌分别在表面模式、断层显像模式下显像效果较好。结论 STIC技术评价胎儿房室瓣具有一定优势,应用价值较高。

Objective To assess the feasibility of spatio-temporal image correlation（STIC） with three-dimensional ultrasound in observing atrioventricular valves structures and evaluating the circumference and areas of the atrioventricular valves（tricuspid and mitral） of normal fetuses.Methods A cross-sectional study was conducted on 176 fetuses with 20 to 32 gestation weeks.Volume datasets of STIC were acquired for subsequent off-line analysis.Atrioventricular valve structure was observed in different modes.The area and circumference of the valves was obtained manually.Linear regression analysis was used to evaluate the correlation of the areas and circumference with gestational age.Results ①STIC acquisition was successful in 81.82%（144/176） of all examinations.The mitral and tricuspid valve circumference and areas were correlated to the gestational age.The mean value circumference of the tricuspid and mitral valves increased from（2.46±0.23）cm and（2.41±0.35）cm on the 20th week to（3.56±0.21）cm and（3.49±0.25）cm on the 32nd of pregnancy,respectively.The mean value areas of the tricuspid and mitral valves increased from（0.34±0.10）cm2 and（0.36±0.14）cm2 on the 20th week to（0.96±0.23）cm2 and（0.97±0.23）cm2 on the 32nd of pregnancy,respectively.②Compared with two-dimensional ultrasound,STIC improved the imaging of the valves,the atrioventricular valve had good imaging quality in different modes,valve ring and papillary muscle were good in render mode and tomographic ultrasound imaging mode,respectively.Conclusion As a new method of evaluating atrioventricular valve,STIC has certain advantages and application value.