Gabriele Masselli MD, Presenter: Nothing to Disclose

Emanuele Casciani, Abstract Co-Author: Nothing to Disclose

Elisabetta Polettini, Abstract Co-Author: Nothing to Disclose

Roberto Brunelli, Abstract Co-Author: Nothing to Disclose

Maurizio Anceschi, Abstract Co-Author: Nothing to Disclose

Gianfranco Gualdi, Abstract Co-Author: Nothing to Disclose

To determine the value of transabdominal ultrasound (US), transvaginal US, color Doppler US, and magnetic resonance (MR) imaging in the diagnosis of placenta accreta.

Fifty patients in the third trimester of pregnancy who were at risk for placenta accreta underwent color-power Doppler US and MR imaging. Images were interpreted prospectively for signs of accreta by two reviewers. The reviewers' confidence in their diagnosis was graded on a five-point scale.Placental invasion was classified in depth levels and topographic areas in relation to the posterior vesical wall. The final degree of invasion was established during surgery according to clinical and anatomical criteria.

Outcomes at delivery were as follows: normal placenta (n = 31), placenta accreta (n = 12), placenta increta (n=4) and placenta percreta (n=3). Five cases of lower-uterine-segment placenta accreta were diagnosed with a high level of confidence with vaginal and color Doppler US. Ultrasound and Color Doppler showed a sensitivity 77% and specificity 93%, while magnetic resonance imaging showed a sensitivity 91% and specificity 98%. In the three cases of placenta percreta, the placenta demonstrated transmural extension through the uterus and invasion of the bladder wall on MRI, which was not depicted at US. In two patients with a posterior placenta who had previously undergone myomectomy, MR imaging enabled the diagnosis of placenta accreta, which was not depicted at US. In all cases MRI provided topographic information of placental invasion, and in 5 patients, it modified invasion levels.

MRI is useful for identifying the presence and extent of placenta accreta/percreta. MR imaging is superior compared with US and color Doppler US in the depiction of posterior placenta accreta and in the evaluation of invasion of bladder wall. Magnetic resonance imaging turned out to be essential to define the topography and area of placental invasion.

Magnetic resonance imaging turned out to be essential to define the topography and area of placental invasion. MR can allow a reduction in morbidity and a conservative surgery.

Masselli, G, Casciani, E, Polettini, E, Brunelli, R, Anceschi, M, Gualdi, G, MR in the Evaluation of Placenta Accreta: Correlation with Doppler US.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5012827.html