Prenatal ultrasound screening for external ear abnormality in the fetuses.

Jun Wei,Jing Tang,Haitao Ran,Yun Lin,Zhengchun Yang,Suzhen Ran

doi:10.1155/2014/357564

Abstract

Objectives. To investigate the best time of examination and section chosen of routine prenatal ultrasound screening for external ear abnormalities and evaluate the feasibility of examining the fetal external ear with ultrasonography. Methods. From July 2010 until August 2011, 42118 pregnant women with single fetus during 16–40 weeks of pregnancy were enrolled in the study. Fetal auricles and external auditory canal in the second trimester of pregnancy were evaluated by routine color Doppler ultrasound screening and systematic screening. Ultrasound images of fetal external ears were obtained on transverse-incline view at cervical vertebra level and mandible level and on parasagittal view and coronal view at external ear level. Results. Five fetuses had anomalous ears including bilateral malformed auricles with malformed external auditory canal, unilateral deformed external ear, and unilateral microtia. The detection rate of both auricles was negatively correlated with gestational age. Of the 5843 fetuses undergoing a routine ultrasound screening, 5797 (99.21%) had bilateral auricles. Of the 4955 fetuses following systematic screening, all fetuses (100%) had bilateral auricles. The best time for fetal auricles observation with ultrasonography is 20–24 weeks of pregnancy. Conclusions. Detection of external ear abnormalities may assist in the diagnosis of chromosomal abnormalities.

Highlights

Studies have shown that an incidence of 1 : 6000 until 1 : 6830 newborns has been reported for external ear malformations [1,2,3]
Scanning images of parasagittal view and coronal view at external ear level had a higher detection rate which can be used as standard observation sections for fetal external ear
The detection rate of bilateral ears was negatively correlated with gestational age (r = −0.911, P < 0.01) and was highest between 20 to 24 weeks of gestational age

Summary

Introduction

Studies have shown that an incidence of 1 : 6000 until 1 : 6830 newborns has been reported for external ear malformations [1,2,3]. Ear abnormalities are important in the diagnosis of a variety of congenital malformations or syndromes in newborns [4,5,6]. Dedicated examinations on fetal external ear are imperative. Ultrasonography is, the method of choice for the diagnosis of congenital abnormalities of the fetus [9]. Because of improved ultrasound technology offering better resolution and improvement in knowledge and experience of ultrasound examiners, detection rates of fetal malformations may have increased since the 1990s [10]

Objectives

Methods

Results

Conclusion