Feasibility of prenatal MRI in the diagnosis of fetal external ear developmental malformation / 中华放射学杂志

ABSTRACT

Objective:To discuss the feasibility of prenatal MRI in evaluating fetal auricle developmental malformation and atresia of external auditory canal.Methods:Fifteen pregnant women (aged from 22 to 40 years old, mean age 31.3±5.2 years old) with fetal external ear developmental malformation suspected by ultrasound underwent MR scanning between November 2017 and May 2019. All of them were singleton. The gestational age ranged from 23 weeks to 35 weeks, with an average of (27.5±3.5) weeks. The sensitivity, specificity and accuracy of MRI and ultrasound in the diagnosis of fetal auricle malformation and atresia of external auditory canal were calculated and compared, using postnatal follow-up as the gold standard. Fisher exact test was used to compare the efficacy of MRI and ultrasound in diagnosing atresia of external auditory canal.Results:A total of 30 fetal external ears were detected in 15 fetuses, without auricle absence. Totally 19 external ears with developmental malformation were confirmed by postnatal follow-up, including 19 ears with auricle malformation and 15 ears with external auditory canal atresia. The accuracy of MRI and ultrasound in the diagnosis of auricle malformation was both 100% (19/19). For the diagnosis of external auditory canal atresia, the sensitivity, specificity and accuracy of MRI and ultrasound were 93.3% (14/15), 75.0% (3/4), 89.5% (17/19) and 33.3% (5/15), 25.0% (1/4), 31.6% (6/19), respectively. The sensitivity and accuracy of MRI in the diagnosis of atresia of external auditory canal were significantly higher than those of ultrasound, with statistically significant difference ( P=0.004, 0.001). Conclusion:MRI plays an important role in the diagnosis of fetal external ear developmental malformation, which can be used as an effective supplement to ultrasound, especially for the diagnosis of external auditory atresia.