Comparison of diagnostic accuracy of three-dimensional transvaginal ultrasound and magnetic resonance imaging in the diagnosis of scar pregnancy

OBJECTIVES: To compare the accuracy of three-dimensional transvaginal ultrasound and magnetic resonance imaging in the diagnosis of scar pregnancy. METHODS: The records of 54 patients with scar pregnancy, who underwent three-dimensional transvaginal ultrasound and magnetic resonance imaging (MRI), from June 2015 to November 2021 were reviewed. Surgery / histopathology of operative findings were analyzed as gold standard to compare the diagnosis of the two examination methods. RESULTS: The detection rate of scar pregnancy by three-dimensional transvaginal ultrasound was 94.44%, which was not significantly different from MRI (96.30%, P>0.05). The accuracy, specificity and sensitivity of transvaginal three-dimensional ultrasonography in the diagnosis of scar pregnancy were 94.44%, 66.67% and 96.08%, respectively, and were not significantly different from MRI, 96.30%, 50.00% and 98.08% (P>0.05). The detection rates of yolk sac, embryo and heart tube pulsation by three-dimensional transvaginal ultrasound were higher than those detected by MRI (P<0.05). The detection rates of intrathecal hemorrhage, scar infiltration and uterine hematocele by MRI were significantly higher compared to three-dimensional transvaginal ultrasound (P<0.05). There was no significant difference between the two methods (P>0.05). CONCLUSION: Both three-dimensional transvaginal ultrasound and MRI have good diagnostic efficacy in the diagnosis of scar pregnancy. Detection rates of scar pregnancy diagnostic criteria differ between the two methods, and if necessary, the two methods can be used together, to further improve the diagnostic accuracy of scar pregnancy.