Contribution of three-dimensional ultrasonography in depicting perineal features in cloacal malformation.

Cloacal anomaly is a rare malformation with an incidence of 1 in 50,000 births. The definitive prenatal diagnosis of cloacal dysgenesis sequence is difficult. The use of three-dimensional (3-D) ultrasonography helps to describe the perineum and change diagnosis. In our case report, a large median genital structure was visualized, which was initially considered a penis-like structure, but the 3-D technique showed an enlarged bud. The urethral meatus was at the tip of this smooth structure. The lack of anal structure was clearly demonstrated.