Chen Luyun, Low Lisa Kane, DeLancey John Ol, Ashton-Miller James A
Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA.
School of Nursing and Women׳s Studies, University of Michigan, Ann Arbor, MI, USA.
J Biomech. 2015 Jun 25;48(9):1575-9. doi: 10.1016/j.jbiomech.2015.02.056. Epub 2015 Mar 11.
The perineal body must undergo a remarkable transformation during pregnancy to accommodate an estimated stretch ratio of over 3.3 in order to permit vaginal delivery of the fetal head. Yet measurements of perineal body elastic properties are lacking in vivo, whether in the pregnant or non-pregnant state. The objective of this study, therefore, was to develop a method for measuring perineal body elastic modulus and to test its feasibility in young nulliparous women.
An UltraSONIX RP500 ultrasound system was equipped with elastography software. Approximately 1 Hz free-hand sinusoidal compression loading of the perineum was used to measure the relative stiffness of the perineal body compared to that of a custom reference standoff pad with a modulus of 36.7 kPa. Measurements were made in 20 healthy nulliparous women. Four subjects were invited back for second and third visits to evaluate within- and between-visit repeatability using the coefficient of variation.
The mean ± SD elastic compression modulus of the perineal body was 28.9 ± 4.7 kPa. Within- and between-visit repeatability averaged 3.4% and 8.3%, respectively.
Ultrasound elastography using a standoff pad reference provides a valid method for evaluating the elastic modulus of the perineal body in living women.
在孕期,会阴体必须经历显著的转变,以适应估计超过3.3的拉伸比,从而允许胎儿头部经阴道娩出。然而,无论是在孕期还是非孕期,体内会阴体弹性特性的测量均尚属空白。因此,本研究的目的是开发一种测量会阴体弹性模量的方法,并在年轻未生育女性中测试其可行性。
一台UltraSONIX RP500超声系统配备了弹性成像软件。采用约1 Hz的徒手正弦波压迫加载会阴,以测量会阴体相对于模量为36.7 kPa的定制参考间隔垫的相对硬度。对20名健康未生育女性进行了测量。邀请4名受试者进行第二次和第三次回访,使用变异系数评估访内和访间重复性。
会阴体的平均±标准差弹性压缩模量为28.9±4.7 kPa。访内和访间重复性的平均值分别为3.4%和8.3%。
使用间隔垫参考的超声弹性成像为评估活体女性会阴体的弹性模量提供了一种有效的方法。