Abstract：
We present a case of antenatally detected fetal megacystis caused by an obstructing posterior urethral polyp. Antenatal and postnatal ultrasounds showed bladder wall thickening and bilateral hydroureteronephrosis, most marked antenatally. A working diagnosis of posterior urethral valves was therefore made. However, further postnatal assessment with a micturating cystourethrogram (MCUG) combined with a retrograde urethrogram identified a pedunculated urethral polyp as the cause. The addition of a retrograde urethrogram as an adjunct to the MCUG in the diagnosis of posterior urethral polyp has not previously been reported, and in this case provided diagnostic confidence of this rare condition, allowing for definitive surgical planning.
摘要：
我们介绍了一例由阻塞的后尿道息肉引起的产前检测到的胎儿巨细胞。产前和产后超声显示膀胱壁增厚和双侧输尿管肾积水，最明显的产前标记。因此，对后尿道瓣膜进行了有效诊断。然而,通过排尿性膀胱尿道造影(MCUG)结合逆行尿道造影进一步进行产后评估,确定尿道息肉为病因.在后尿道息肉的诊断中添加逆行尿道造影作为MCUG的辅助手段，以前没有报道过。在这种情况下，提供了这种罕见情况的诊断信心，允许明确的手术计划。
