Cord vessel compression by an expanding allantoic cyst: case report

Abstract

The umbilical cord has been inadequately studied by ultrasound. Umbilical cord masses are rare and often misdiagnosed. A case of a 4.3 × 3.2 cm anechoic floating cystic umbilical mass is reported. Doppler examination of the cord proximal to the cyst revealed a high resistance index of 0.84. Twelve hours later the cyst was larger (5.0 × 4.5 cm) and appeared tense; Doppler velocimetry worsened and absence of end‐diastolic flow in the umbilical artery was found. Cardiotocography a few hours later showed a bradycardiac non‐reactive trace with late decelerations. A live male weighing 1980 g was delivered by Cesarean section. At birth the cord position was normal. Pathological examination showed the lesion to be consistent with an allantoic cyst. This is the first case in which antenatal evidence of cord compression by an expanding allantoic cyst has been demonstrated. Copyright © 1992 International Society of Ultrasound in Obstetrics and Gynecology Copyright © 1992 International Society of Ultrasound in Obstetrics and Gynecology