产前MRI评估胎儿外耳发育畸形的可行性研究

Feasibility of prenatal MRI in the diagnosis of fetal external ear developmental malformation

目的探讨产前MRI评估胎儿耳廓发育畸形及外耳道闭锁的可行性。方法对2017年11月至2019年5月山东省医学影像学研究所超声疑诊胎儿外耳发育畸形的15例孕妇行胎儿外耳MRI检查,孕妇年龄22.0~40.0(31.3±5.2)岁,均为单胎,孕龄23~35(27.5±3.5)周。以出生后随访结果为金标准,计算并比较MRI和超声诊断胎儿耳廓发育畸形及外耳道闭锁的灵敏度、特异度和准确率。采用Fisher精确检验法比较MRI和超声诊断外耳道闭锁的效能。结果15例胎儿MRI显示胎儿外耳30侧,无耳廓缺如者,出生后随访证实外耳畸形19侧,其中耳廓畸形19侧,外耳道闭锁15侧。MRI及超声诊断耳廓畸形的准确率均为100%(19/19)。MRI及超声诊断外耳道闭锁的灵敏度、特异度、准确率分别为93.3%(14/15)、75.0%(3/4)、89.5%(17/19)和33.3%(5/15)、25.0%(1/4)、31.6%(6/19)。MRI诊断外耳道闭锁的灵敏度、准确率明显高于超声,差异有统计学意义(P=0.004、0.001)。结论MRI对胎儿外耳发育畸形具有重要诊断价值,可作为超声的有效补充,尤其是诊断外耳道闭锁有明显优势。

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.