Ivan Maria, Mahdy Heba, Banerjee Amrita, Tetteh Amos, Greenwold Natalie, Casagrandi Davide, Jurkovic Davor, Napolitano Raffaele, David Anna L
Fetal Medicine Unit, University College London Hospital NHS Foundation Trust, London, UK.
Research Department of Maternal Fetal Medicine, Elizabeth Garett Anderson Institute for Women's Health, University College London, London, UK.
J Ultrasound Med. 2025 Mar;44(3):509-519. doi: 10.1002/jum.16613. Epub 2024 Nov 7.
To assess the reproducibility of standardized 3-dimensional (3D) ultrasound volume analysis of the dimensions and the position of cesarean birth (CB) scar niche relative to the cervix in pregnant women.
This prospective single-center study in women with 1 previous CB ≥8 cm cervical dilatation acquired ultrasound volumes between 11 and 24 weeks' gestation in a mid-sagittal plane. Two experienced operators processed the volumes using virtual organ computer-aided analysis. A CB scar niche was defined as an indentation at the scar site of ≥2 mm in depth. Niche and cervix volumes were calculated using manual contouring. Agreement for categorical variables was expressed using intraclass correlation coefficient (ICC). The Bland-Altman method was used to assess numerical variable reproducibility.
To achieve the desired statistical power, 52 participants were included. The intraobserver agreement on niche classification relative to the internal os was 100%, with an interobserver kappa coefficient of 0.98 (95% confidence interval [CI] 0.97-0.99, P < .05). The intraobserver ICC for niche volume was 0.94 (95% CI 0.90-0.96; P < .001), with a mean difference of -15.32 mm (±109.32). The interobserver ICC was 0.78 (95% CI 0.62-0.87; P < .001), with a mean difference of -21.57 mm (±202.01). The ICC for niche/cervix volume ratio were 0.94 (95% CI 0.90-0.96; P < .001) and 0.79 (95% CI 0.63-0.87; P < .001) for intra- and interobserver reproducibility, respectively.
This study demonstrates that 3D CB scar sonographic features are highly reproducible in pregnant women with a history of advanced labor CB. The validated protocol can guide future research on the association with subsequent adverse pregnancy outcomes.
评估标准化三维（3D）超声容积分析剖宫产（CB）瘢痕憩室相对于宫颈的尺寸和位置在孕妇中的可重复性。
这项前瞻性单中心研究纳入有过一次宫颈扩张≥8 cm的剖宫产史的女性，在妊娠11至24周时获取正中矢状面的超声容积数据。两名经验丰富的操作人员使用虚拟器官计算机辅助分析处理这些容积数据。CB瘢痕憩室定义为瘢痕部位深度≥2 mm的凹陷。使用手动勾勒轮廓计算憩室和宫颈的容积。分类变量的一致性用组内相关系数（ICC）表示。采用Bland-Altman方法评估数值变量的可重复性。
为达到所需的统计效能，纳入了52名参与者。观察者内关于憩室相对于宫颈内口分类的一致性为100%，观察者间kappa系数为0.98（95%置信区间[CI] 0.97 - 0.99，P <.05）。观察者内憩室容积的ICC为0.94（95% CI 0.90 - 0.96；P <.001），平均差值为 - 15.32 mm（±109.32）。观察者间ICC为0.78（95% CI 0.62 - 0.87；P <.001），平均差值为 - 21.57 mm（±202.01）。观察者内和观察者间憩室/宫颈容积比的ICC分别为0.94（95% CI 0.90 - 0.96；P <.001）和0.79（95% CI 0.63 - 0.87；P <.001）。
本研究表明，有晚期产程剖宫产史孕妇的3D CB瘢痕超声特征具有高度可重复性。经验证的方案可为未来关于与后续不良妊娠结局关联的研究提供指导。
