Accuracy of ultrasound and magnetic resonance imaging in predicting placenta accreta: A retrospective study

Background: Placenta accreta can cause significant morbidity and mortality in pregnant women. Timely diagnosis is essential for management. This study aimed to evaluate the accuracy of ultrasound (USG) and magnetic resonance imaging (MRI) techniques in predicting placenta accreta. Methodology: A retrospective study was conducted at our institute from April 2014 to September 2017. Pregnant women with suspected placenta accrete were recruited for the study. Medical records of pregnant women who have undergone both USG and prenatal MRI were included. The accuracy of USG and MRI was compared. Results: Among the 56 cases evaluated in the study, the diagnosis was accurately obtained with ultrasonography in 75% of cases and with MRI in 68.51% of cases. Sensitivity for placenta accreta was 97.29% for USG and 78.37% for MRI. Specificities were 31.57% for USG and 47.05% for MRI. The positive predictive value was 73.46% for USG and 76.31% for MRI. Conclusion: Although a definite demarcation could not be obtained from the sensitivity, specificity, and positive predictive value of the placenta accrete with ultrasonography and MRI, the diagnostic accuracy may be taken as a definite pointer. Hence, ultrasonography remains the mainstay of diagnosis for placenta accrete; and MRI can be considered complementary in cases with few USG signs.