Agarwal Shubhra, Agarwal Arjit, Chandak Shruti
Department of Radiodiagnosis, Teerthanker Mahaveer Medical College & Research Centre, Teerthanker Mahaveer University, Moradabad, India.
Department of Obstetrics & Gynecology, Teerthanker Mahaveer Medical College & Research Centre, Teerthanker Mahaveer University, Moradabad, India.
Ultrasound. 2021 May;29(2):92-99. doi: 10.1177/1742271X20959742. Epub 2020 Sep 22.
To estimate the level of interobserver agreement in the calculation of placenta accreta index (PAI) as well as to evaluate the accuracy of PAI in prediction of morbidly adherent placenta.
This was a prospective study where 45 pregnant women (from 28 to 37 weeks of gestational age) with at least one previous Caesarean section and ultrasound-proven placenta previa were included. A known and previously published scoring system, the PAI, was evaluated independently by two radiologists and the cases were followed for the delivery and histopathology outcome. The accuracy of the PAI and the level of interrater agreement was analysed using cross-table analysis, intraclass correlation efficient and Cohen's kappa as statistical variables.
Adherent placenta was found in 15 patients accounting for 33% of cases. The PAI showed nearly 90% sensitivity, specificity and the predictive values. Interrater agreement in calculation of PAI by the two radiologists was perfect with an intraclass correlation efficient of 0.959. An easy-to-use morbid adherent placenta score was also predicted to simplify the results of PAI, which showed moderate agreement (κ = 0.746).
The PAI can be helpful in stratifying the individual risk of placental invasion above the baseline risk. The PAI-derived, simplified scoring system called morbid adherent placenta score can be used as a simple tool to interpret and convey the results of PAI.
评估胎盘植入指数(PAI)计算过程中观察者间的一致性水平,并评价PAI预测胎盘植入异常的准确性。
这是一项前瞻性研究,纳入了45例孕周为28至37周、有至少一次剖宫产史且经超声证实为前置胎盘的孕妇。由两名放射科医生独立评估一种已知且先前已发表的评分系统——PAI,并对病例进行随访直至分娩及组织病理学结果。使用交叉表分析、组内相关系数和科恩kappa系数作为统计变量,分析PAI的准确性和评估者间的一致性水平。
15例患者发现胎盘植入,占病例的33%。PAI显示出近90%的敏感性、特异性和预测值。两名放射科医生计算PAI时的评估者间一致性极佳,组内相关系数为0.959。还预测了一种易于使用的胎盘植入异常评分,以简化PAI的结果,其显示出中度一致性(κ = 0.746)。
PAI有助于在基线风险之上对个体胎盘植入风险进行分层。源自PAI的简化评分系统——胎盘植入异常评分,可作为解释和传达PAI结果的简单工具。