MRI量化指标对胎盘植入及剖宫术后大出血的预测价值

Predictive value of MRI quantitative index for placenta implantation and massive hemorrhage after cesarean section

目的:探讨不同胎盘植入类型、范围在磁共振成像(MRI)中的表现及其对剖宫术后大出血的预测价值。方法:选取2014年1月至2017年12月间宜宾市第一人民医院收治的380例前置胎盘患者为研究对象,根据术中所见和病理检查结果分为观察组(胎盘植入患者)和对照组(非胎盘植入患者),所有患者术前均行MRI检查,观察MRI的征象与胎盘植入的分类、分级及术后大出血之间的关系。结果:MRI上子宫肌层变薄、胎盘-肌层界面消失、T2WI胎盘内低信号带、子宫轮廓外凸等征象两组比较,差异均有统计学意义(P <0. 05)。MRI显示25例为粘连型胎盘植入,而术中及病理学结果证实有19例为粘连型胎盘植入;MRI显示有208例为植入型胎盘,而术中及病理学结果证实有197例为植入型胎盘;MRI显示8例为穿透型胎盘植入,而术中及病理学结果也证实有8例为穿透型胎盘植入;MRI显示139例患者为胎盘植入阴性,而术中及病理学结果证实有116例为胎盘植入阴性。MRI诊断子宫肌层变薄、胎盘-肌层界面消失、T2WI胎盘内低信号带、子宫轮廓外凸的诊断准确率分别为78. 16%、85. 79%、68. 95%、88. 42%。MRI的胎盘植入的分级越高,发生术后大出血的风险越高,且差异有统计学意义(P <0. 05)。结论:MRI对胎盘植入有较高的诊断价值,能对胎盘植入进行有效的分级,对产后大出血有较高的预测价值,可以为临床治疗提供依据。

Objective: To explore the manifestations of different types and extents placental implants in magnetic resonance imaging( MRI) and its predictive value of massive hemorrhage after cesarean section. Methods: A total of 380 patients with placenta previa were enrolled in this study from January 2014 to December 2017 in Yibin First People’s Hospital. The patients were divided into the observation group( placenta implanted patients) and the control group( non-placenta implanted patients) according to intraoperative and pathological findings. All patients underwent MRI before surgery,and the relationship between MRI manifestations and classification,grading and postoperative hemorrhage were investigated. Results: MRI results showed that there were significantly different in the signs of myometrial thinning,placental-muscle interface disappearance,T2 WI placental low signal band,uterine contour convex between the observation group and the control group( P < 0. 05). MRI showed 25 cases were adhesion-type placenta,while intraoperative and pathological results verified 19 cases. MRI showed 208 cases were implanted placentas,while intraoperative and pathological results verified 197 cases. MRI showed 8 cases were penetrating placenta,while intraoperative and pathological results also verified 8 cases. MRI showed 139 patients with negative placenta,while intraoperative and pathological findings verified 116 patients. The diagnostic accuracy of MRI diagnosis of myometrial thinning,placental-muscle interface disappearance,low signal band in T2 WI placenta,and kyphosis were 78. 16%,85. 79%,68. 95%,88. 42%,respectively. The higher grade of placenta implantation by MRI,the higher risk of postoperative hemorrhage,and the difference was significance( P < 0. 05).Conclusion: MRI has a high diagnostic value for placental implantation and can effectively classify placenta implants. It has a great predictive value for postpartum hemorrhage and can provide a basis for clinical treatment.