Multisystemic Anomalies in Conjoined Twins: The Role of Imaging in Management

Conjoined twins (CT) represent one of the rarest and most challenging congenital malformations arising as an unfortunate complication of monozygous twinning, with an estimated incidence ranging from 1 in 50,000 to 100,000 pregnancies, with an overall true incidence of about 1 in 200,000 live births with around 60% of them being stillborn. The types of the twins may differ depending on the site of fusion or nonseparation. The most commonly encountered types are thoraco-omphalopagus (28%), thoracopagus (18%), omphalopagus (10%), parasitic twins (10%), pygopagus (6–19%), and craniopagus (6%), with the pygopagus twins having the highest survival rate. Because of the highly variable and complex anatomy and associated malformations, skilled clinical assessments aided by detailed radiological studies, appropriate planning, and teamwork are required for the successful separation of the CT. The role of imaging in the diagnosis and management of missed diagnosed intrauterine case of pygopagus type CT was presented. At delivery, they were found to have sacral fusion on radiography with distal, rectal fusion on limited barium enema. Magnetic resonance imaging demonstrated distal spinal cord fusion with vascular anomaly found on computed tomography angiography. The surgical separation of the patients was successful with satisfactory postoperative lives.