Gabriele Masselli MD, Presenter: Nothing to Disclose

Roberto Brunelli, Abstract Co-Author: Nothing to Disclose

Emanuele Casciani, Abstract Co-Author: Nothing to Disclose

Elisabetta Polettini, Abstract Co-Author: Nothing to Disclose

Dino D'Amico, Abstract Co-Author: Nothing to Disclose

Gian Franco Gualdi MD, Abstract Co-Author: Nothing to Disclose

To compare the accuracy of magnetic resonance (MRI) and colour Doppler-ultrasound (US) in the diagnosis of late pregnancy bleeding and to assess the accuracy of the different MR sequences in visualizing the origin of haemorrhage.

This study protocol was approved by our institutional review board. 55 patients in the third trimester of pregnancy underwent to US and MRI for the evaluation of painless vaginal bleeding; written informed consent was obtained from all patients included in the study.  Multiplanar HASTE, True Fisp, 3D T1 GRE and sagittal DWI sequences were acquired. Two radiologists, blinded to the results of US, reviewed each case, resolving by consensus any discrepancy. Reference standards were surgical and pathological findings. Diagnostic efficacy of US and MRI were calculated with 95% confidence intervals. Interobserver agreement was assessed using the Cohen’s k test.

The reference standards identified 25 placenta previa, 13 placental abruptions (1 coincident with a placental chorioangioma), 1 thrombohaematoma and 3 fibroma with haemorrhagic degeneration. MRI identified correctly all these condition with an interobserver agreement of 0.955. DWI and T1 weighted sequences were statistically superior to Haste and True Fisp sequences in detecting the cause of bleeding (p < .001). US had 7 false negatives and 2 false positive results, its diagnostic accuracy resulting lower than MRI (p = .001). The interobserver agreement of MRI examinations was extremely high (k ranging from 0.785 to 1.000 in the different sequences).   

MRI accurately evaluates pregnancy bleeding with an excellent interobserver agreement and can grant new and additional data when US is negative.

In patients with late pregnancy bleeding, MRI provides a complete non invasive assessment with excellent accuracy and with useful information for the management of these patients.

Masselli, G, Brunelli, R, Casciani, E, Polettini, E, D'Amico, D, Gualdi, G, Magnetic Resonance Imaging of Late Pregnancy Bleeding.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12032724.html