Multiple fetuses in fetu:imaging findings.

Fetus in fetu is an extremely rare developmental abnormality secondary to abnormal embryogenesis in a diamniotic monochorionic pregnancy. It occurs when a vertebrate fetus is enclosed within the abdomen of a normally developing fetus. This report describes the prospective diagnosis of fetus in fetu by findings on a plain radiograph and CT scan. At surgery, two fetus in fetu were discovered.