Fetal retroesophageal left brachiocephalic vein with U‐shaped vascular ring on four‐dimensional color Doppler ultrasound

Retroesophageal or retrotracheal left brachiocephalic vein (LBCV) is a very rare anomaly, first described by Yigit et al.1 Subsequently, a study was conducted using computed tomography to examine LBCV in children,2 and a case of fetal retrotracheal LBCV with a complex cardiac anomaly has been reported.3 In addition, the prenatal evaluation of fetal LBCV and the normal reference ranges for LBCV have been established.4