Prenatal diagnostic performance of combined ultrasonography and magnetic resonance imaging for placenta accreta in pregnant women

Objective To evaluate the prenatal diagnostic performance of combined ultrasonography and magnetic resonance imaging (MRI) for placenta accreta in pregnant women. Methods A total of 65 patients with suspected prenatal placenta accreta admitted to our hospital from January 2019 to December 2023 were enrolled. Preoperative ultrasonography and MRI fin-dings (including all MRI signs), as well as postoperative pathological findings, were collected. The final diagnosis for each patient was based on the surgical pathology results. A receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic performance of each modality, and Kappa statistics were applied to compare the consistency of ultrasonography, MRI, and combined ultrasonography and MRI with surgical pathological results. Results Among the 65 patients, 54 cases of placenta accreta were confirmed by surgical pathology. Ultrasonography showed a sensitivity of 100.00%, but a relatively low specificity (45.45%) and an accuracy of 90.77%, demonstrating moderate agreement with the pathological results (Kappa=0.581). MRI exhibited high sensitivity (96.30%) and specificity (100.00%), with an accuracy of 96.92% and strong agreement with the pathological results (Kappa=0.898). Combined ultrasonography and MRI achieved 100.00% sensitivity, specificity, and accuracy, and yielded perfect agreement with the pathological results (Kappa=1.000). Among the MRI signs, “intraplacental dark bands or he-terogenous signal intensity” showed the highest sensitivity (92.59%), while “interruption of low-signal myometrial band or discontinuous” demonstrated the highest specificity (100.00%). Conclusion Combined ultrasonography and MRI provide superior prenatal diagnostic performance for placenta accreta compared with either modality alone, significantly improving diagnostic accuracy and reliability.