Addressing surgical challenges in craniopagus twin separation surgery: A systematic review

Challenges in craniopagus twin separation surgery

Abstract

Craniopagus twins (CPTs) are conjoined twins fused at homologous regions of the crania in either vertical or angular orientations, with the face and foramen magnum spared. They account for approximately 6% of conjoined twins and occur in 0.6 per million births worldwide. The degree of circulatory interconnection is a central consideration when planning separation surgery, particularly when deciding between a single-stage and a multistage approach. In craniopagus twins with fused dural venous sinuses, the superior sagittal sinus is replaced by a circumferential venous sinus (CVS); these cases are classified as total CPTs. Surgical challenges become increasingly complex in the presence of a CVS, prolonged anesthetic exposure, substantial cross-circulation, and the unique anatomical position of the twins. This review compiles data on the surgical management of these challenges and their outcomes, contributing to the continued development and refinement of surgical planning in CPT separation surgery. A Google Scholar search restricted to English-language articles published from 2020 to 2024 identified 329 articles. After detailed review, 19 open-access articles were selected for this manuscript. The reviewed literature showed that the degree of cross-circulation can be assessed through laboratory and physiologic measurements after pharmacologic challenges and can be mapped using multiple imaging modalities. The data also showed that a multistage surgical approach is preferentially selected for total CPTs because it reduces the high risks of hemorrhage, ischemic brain injury, and neurotoxicity associated with a CVS and extensively connected circulatory systems. In addition, staged surgery limits anesthetic exposure, decreasing the risk of anesthesia-induced cerebrospinal fluid stasis and hypotension. It also allows cerebral vasculature to redevelop between operations, thereby supporting adequate venous drainage. During surgery, each twin, their equipment, and their care team should be labeled with a number, letter, and color to provide safe and efficient patient care. This literature review maintains the clinical relevance of craniopagus twin separation surgery by presenting an up-to-date summary of methods and protocols designed to ensure surgical precision and safety when unique preoperative and perioperative challenges arise.