超声阴性胎盘早剥MRI表现及其诊断价值

MRI manifestations and diagnostic value of placental abruption with negative sonographic findings

目的观察超声无阳性发现的胎盘早剥的MRI表现及其诊断价值。方法收集53例产后确认为胎盘早剥孕妇的产前MRI,观察胎盘位置、血肿位置、分期及其与胎盘早剥分型和妊娠结局的关系。结果16例胎盘位于子宫前壁及侧壁,37例胎盘位于子宫底及后壁。53例均可见胎盘血肿;29例血肿位于胎盘绒毛膜下,表现为新月形和弧形异常信号,T1WI、T2WI及DWI多呈高信号;24例血肿位于底蜕膜下,其中9例单纯底蜕膜下血肿表现为三角形和梭形异常信号,T1WI多呈等信号、T2WI及DWI呈高信号,15例绒毛膜及底蜕膜下连续血肿表现为梭形、弧形或新月形异常信号,T1WI和T2WI多呈高信号,DWI呈低信号。32例血肿渗透至胎盘内,其中16例胎盘增厚。34例胎盘与子宫壁分离,胎盘母体面与子宫肌层之间存在间隙。不同位置胎盘早剥分型和妊娠结局差异均无统计学意义(P均>0.05)。底蜕膜下血肿较绒毛膜下血肿、急性期血肿较非急性期血肿更易发生重型胎盘早剥及接受急诊剖宫产(P均<0.05)。结论MRI有助于判断胎盘血肿位置及分期,预测胎盘早剥分型;发现底蜕膜下急性出血时应予紧急处理。

Objective To observe MRI manifestations and diagnostic value of placental abruption with negative sonographic findings.Methods MRI data of 53 pregnant women with placental abruption were collected.The location of placental abruption,location and stage of hematoma,and the relationships with the classification of placental abruption and pregnancy outcomes were observed.Results Sixteen placentas located on the anterior and lateral wall of uterus,while 37 placentas located on the fundus and posterior wall of uterus.Placental hematomas were detected in all 53 cases,including 29 of hematoma located under placental chorion,showing crescent and arc high signals on T1WI,T2WI and DWI,while 24 of hematoma located under the basal decidua,9 of simple basal decidual hematoma showing triangular and fusiformis equal signals on T1WI and high signals on T2WI and DWI,and 15 of continuous hematoma of chorion and basal decidua,showing fusiformis,arc or crescent abnormal high signals on T1WI and T2WI and low signals on DWI.Hematoma infiltrated into the placenta in 32 cases,among them 16 cases showed placental thickening.The placenta separated from the uterine wall in 34 cases,and a gap between them was found.There was no significant difference of the classification nor pregnancy outcome of placental abruption at different locations(both P>0.05).Hematoma under basal decidua and acute hematoma were more prone to severe placental abruption and emergency cesarean section than hematoma under placental chorion and non-acute hematoma(both P<0.05).Conclusion MRI was helpful to judge the location and stage of placental hematoma,predict the classification of placental abruption.Prompt emergency treatment was necessary when acute hemorrhage under basal decidua was detected.