MINIMALLY CONJOINED OMPHALOPAGI - A CONSISTENT SPECTRUM OF ANOMALIES

Omphalapagus twins constitute less than one third of all siamese twins . Most omphalopagi are attached by a skin bridge that often contains h epatic tissue. Only four cases of omphalopagi attached by an intestina l bridge have been reported. The authors present two additional cases of conjoined twins minimally attached by a small bowel and bladder bri dge. In both instances, the spectrum of anomalies included a ruptured omphalocele and imperforate anus with cloacal anomalies. The attachmen t consisted of an open urachal remnant joining the two bladders, and t he short small bowel of twin A attached to the terminal ileum of twin B. Separation was uneventful. For one set of twins, the case part of t he proximal colon of twin B was used to lengthen the bowel of twin A. Three of the twins survived and underwent additional procedures for re pair of the cloacal anomalies. All four previously reported cases of m inimally conjoined omphalopagi presented with a remarkably similar spe ctrum of anomalies. All had ruptured omphaloceles. imperforate anus wi th cloacal anomalies, and urachal anomalies. intestinal connection was consistently at a point corresponding to the Meckel diverticulum site of twin B, with blood supply to the small bowel of twin A, probably v ia the vitelline artery. The consistent spectrum of anomalies encounte red with minimally conjoined omphalopagi allows planning of separation . Caution is required to avoid overlooking the patent urachus, and int estinal lengthening procedures based on the vitelline artery become an important consideration. Copyright (C) 1994 by W.B. Saunders Company