The Value Of Magnetic Resonance Imaging In The Diagnosis Of Placenta Previa And Placenta Implantation, And Analysis And Comparison Of Ultrasound Diagnosis

Objective To evaluate the diagnostic value of magnetic resonance imaging in thediagnosis of placenta and placenta and to explore the imaging features of MRI inplacenta.,contrast and analysis the coincidence rate of MRI and ultrasound in the diagnosis ofplacenta and placenta.Methods A retrospective analysis of56patients underwent cesarean section andcurettage in No.1Hospital of Jilin University from2014September to2015March.Postoperative pathological results for56cases of placenta previa,14cases of placenta,placenta accreta15cases (placenta previa with accreta postpartum1case). All patientsunderwent magnetic resonance imaging and ultrasonography (US). The MRI imaging ofplacenta accreta imaging signs to be a summary and classification, mainly related to uterinelower segment deformation or local uplift and T2WI appeared low signal penumbra, localimplantation increased flow void vessels and placental signals, cervix hemorrhage andplacenta adjacent uterine muscular layer variable thin or disappeared6imagingmanifestations and the patients were divided into the placenta implantation group and thecontrol group (non placenta accreta group), for each MRI signs of Fisher’s exact test for thestatistical analysis. To in the group of patients with placenta previa and placenta implantationMRI and ultrasound examination results and operation results (gold standard) were comparedusing a paired fourfold table chi square test of coincidence rate of whether there is asignificant difference. In the above research, when the test results P<0.05, there werestatistically significant differences.Results MRI placenta location, shape, boundary, internal signal and vasculardistribution clearly show signs of placenta implantation, has obvious specificity in MRI imaging on the imaging, after the study found in placenta implantation group and controlgroup, the lower uterine segment deformation or local uplift, T2WI like low signal dark bandlocal flow void blood vessels increased, implantation of placenta, heterogeneous, cervixhemorrhage and placenta adjacent myometrial thinning or disappeared in6in the placentaimplantation group and control group were25cases and4cases,20cases and1cases,24cases and2cases,11cases and10cases in10cases, and9cases,11cases and9cases, theresults of statistical signs before three P<0.05, is considered to be the special signs of MRIimaging study of placenta implantation. On the basis of all enrolled in placenta of patientswith MRI and ultrasound are the two imaging diagnostic coincidence rate comparison, in linewith MRI and ultrasound diagnosis of placenta previa was significantly different, MRI in thediagnosis of placenta previa with rate was100%, significantly higher than the ultrasound. Inaddition, the diagnostic accuracy of MRI placenta implantation was83.93%, ultrasound was71.43%, and the difference was statistically between two, MRI was higher than ultrasound. The diagnosis of posterior wall placental implantation was the same as that of the posteriorwall, and the diagnostic accuracy of MRI to posterior wall was80%, and that of ultrasoundwas64%, and the difference was statistically significant between the two.Conclusion Uterine lower segment deformation or local uplift and T2WI appeared lowsignal penumbra, local implantation of increased vascular signal void shadow for placentaaccreta in MRI imaging specific signs. The diagnostic accuracy of MRI for placenta andplacenta is higher than that of ultrasound, and can be used as a routine method for placentaimplantation, and better preoperative evaluation.