Epigastric heteropagus twinning.

Conjoined twins is a very rare condition that represents, sometimes, a real challenge for pediatric surgeons. There is an even rarer situation, called heteropagus twinning, when one of the twins is not completely formed (parasite) and dependent of the well-formed one (autosite). The authors present a case of heteropagus twins in which the parasite was attached to the epigastrium of the autosite. In this situation, the separation procedure may be quite simple if a well-done anatomic study using x-ray, ultrasonography, computed tomography (CT) scan, magnetic resonance, and echocardiogram are performed. The precise knowledge of the anatomic variability and physiologic changes of both twins will help the surgeon make decisions like which surgical approach to use and the dissection tactic to be used. The pediatric surgeon also must be aware of the necessity to improvise during the operation. Copyright 2001 by W.B. Saunders Company.