Perinatology Unit, Carabobo University, Valencia - Venezuela. UPUC@hotmail.com
This fetus has cloacal dysgenesis with imperforated anus. There is no connection of the cloaca with the amniotic cavity (anhydramnios). The resulting renal dysplasia caused enlargement of the kidneys that present a cystic appearance. Note the abnormal position of the iliac arteries dues to the compression by the kidneys. Flow to the kidneys and lung demonstrate a high impedance.
The cloaca is the oblong pelvic cyst with the rectum on the posterior aspect and the bladder on the anterior aspect.