Surgical experience with thirteen conjoined twins.

Conjoined twins occur in approximately one in 50,000 or so births, and most do not survive. The authors report herein their experience with 13 conjoined twins over the last 30 years, involving those of the following forms: thoracopagus (4 cases), omphalopagus (1 case), ischiopagus (4 cases), pygopagus (1 case), craniopagus (1 case), and incomplete or parasitic varieties (2 cases). The various diagnostic and imaging studies used are described in detail for each form of twinning. Separation is best delayed until such infants are relatively mature (i.e., 6-12 months of age). Operative survival was 50% in those operated on in the neonatal period, but 90% in those over 4 months of age. Ten separations were attempted in 13 sets of twins, with 16 operative survivors. Significantly, up to 10 years after surgery, there were six late deaths due to serious associated congenital anomalies, predominantly cardiac. Improved recent survival is probably the result of the availability of more accurate imaging studies and better anesthetic and operative techniques, with great emphasis on performing immediate reconstruction whenever possible. Use of skin expanders and prosthetic mesh has facilitated wound closure. In the future, ex vivo cardiac reconstruction and autotransplantation may permit separation of twins with complicated conjoined hearts.