Tissue expansion and heterologous mesh for abdominal wall reconstruction in the surgical separation of conjoined twins: A case series

Introduction: Conjoined twin abdominal separation is a rare operation that requires complex closure techniques to ensure abdominal wall stability, visceral protection, and adequate skin closure. This study evaluates outcomes after the use of tissue expanders in abdominal wall reconstruction in omphalopagus twin pairs separation. Methods: A retrospective study of all conjoined twin separations was analyzed between 1991-2020 at a tertiary medical center with two-staged tissue expander-based abdominal wall reconstruction performed by the senior surgeon (U.B). The operative technique is outlined. Demographic, operative, and postoperative outcomes were abstracted from the medical records. Results: A total of 4 pairs (3 females, 1 male) were included in the study and all achieved successful separation. The average age at expander placement was 207 days old (range:11-670) and 265 days old (53-732) for separation. Expanders averaged 57 cc in volume with 44 days of expansion. There was one early explantation due to port exposure, 3 post-separation delayed wound healings, and one abdominal compartment syndrome. The median long-term follow-up was 14.5 years. In the long term, 3 patients developed minor abdominal hernias requiring no intervention. Discussion: Expansive abdominal wall defects after omphalopagus twin separation present a challenging situation with a deficiency in donor site availability that precludes traditional local or flap reconstruction. This study demonstrated our tissue expansion technique in the