Maternité, Université Paris Descartes, Faculté de Médecine, AP-HP, Hôpital Necker-Enfants Malades, Paris, France.
Ultrasound Obstet Gynecol. 2009 Oct;34(4):419-23. doi: 10.1002/uog.6413.
Posterior urethral valves (PUV) are the most common cause of renal impairment in boys during early childhood. Although antenatal suspicion of this pathology has become quite common in recent years, prenatal diagnosis remains challenging. The aim of this study was to evaluate the predictive value of different ultrasound criteria currently used to diagnose PUV.
We reviewed the antenatal and postnatal files of 54 male patients referred to our center from 2000 to 2006 after detection of fetal bilateral hydronephrosis. The following ultrasound criteria were evaluated in relation to the postnatal diagnosis of PUV: amniotic fluid volume, bladder wall thickness, bladder dilatation and the presence of the 'keyhole sign'.
Forty-two fetuses (77.8%) were suspected to have PUV on prenatal examination. Out of these, 29 (69.0%) had PUV confirmed postnatally. The sensitivity and specificity of the antenatal diagnosis of PUV were 94% and 43%, respectively. Increased bladder wall thickness and bladder dilatation were highly associated with the diagnosis of PUV (P < 0.001). However, a thick-walled bladder was observed in 39.1% and a dilated bladder in 47.8% of the infants with a postnatal diagnosis other than PUV. The presence of the keyhole sign was not found to predict a diagnosis of PUV (P = 0.27).
In this series the use of classical prenatal ultrasound signs to diagnose PUV showed high sensitivity but low specificity. The best diagnostic indicators were increased bladder wall thickness and dilatation of the bladder. The keyhole sign was not found to be a reliable predictor of PUV.
后尿道瓣膜（PUV）是幼儿期男性肾功能损害的最常见原因。尽管近年来对此病理学的产前怀疑已变得相当普遍，但产前诊断仍然具有挑战性。本研究旨在评估目前用于诊断 PUV 的不同超声标准的预测值。
我们回顾了 2000 年至 2006 年间因胎儿双侧肾积水而转诊至我们中心的 54 名男性患者的产前和产后病历。评估了与 PUV 产后诊断相关的以下超声标准：羊水体积、膀胱壁厚度、膀胱扩张和“钥匙孔征”的存在。
42 例胎儿（77.8%）在产前检查中被怀疑患有 PUV。其中，29 例（69.0%）在产后得到证实。PUV 的产前诊断的敏感性和特异性分别为 94%和 43%。膀胱壁增厚和膀胱扩张增加与 PUV 的诊断高度相关（P<0.001）。然而，在产后诊断为非 PUV 的婴儿中，观察到厚壁膀胱的比例为 39.1%，扩张膀胱的比例为 47.8%。未发现“钥匙孔征”可预测 PUV 的诊断（P=0.27）。
在本系列中，使用经典的产前超声征象诊断 PUV 具有高敏感性但特异性低。最佳的诊断指标是膀胱壁厚度增加和膀胱扩张。“钥匙孔征”不能作为 PUV 的可靠预测指标。
