MRI appearance of placenta percreta and placenta accreta

The purpose of this paper is to describe the magnetic resonance imaging (MR ) features of placenta accreta and percreta, We retrospectively reviewed MR I findings in four cases of placenta accreta/percreta to determine features which assist in identifying the presence and extent of placental implantat ion abnormality. All patients had ultrasound (US) examinations. Pathologic correlation was available in all cases. There were two cases of placenta pe rcreta and two cases of placenta accreta, All cases were treated by hystere ctomy. In the two cases of placenta percreta, the placenta demonstrated tra nsmural extension through the uterus (percreta) on MRI. In the two cases of placenta accreta, the location of thinning in the uterine wall correlated, vith the location of placental invagination into the myometrium at patholog y, US correlation was available in all four cases. Gray scale US did not de monstrate placental invasion in any of the four cases of placenta accreta/p ercreta, however, in two of three cases in which color Doppler was performe d, there was flow at the uterine margin suspicious for implantation abnorma lity. In conclusion, MRI is useful for identifying the presence and extent of placenta accreta/percreta. (C) 1999 Elsevier Science Inc.