Hepatic separation of conjoined twins: Operative technique and review of three-dimensional model utilization

Background: The separation of conjoined twins is a challenging and rare operation. Recent technological advances in imaging and three-dimensional printing (3DP) have allowed for enhancements in preoperative surgical planning and intraoperative anatomical orientation for complex operations. This report aims to consolidate the current clinical evidence utilizing 3DP models as an effective tool for surgical planning of conjoined twin separation and to detail our surgical approach for complex hepatic separation and management. Methods: A literature review was conducted for conjoined twin separations with preoperative use of 3D models including age at attempted separation, operative outcome, 3D modality, and postoperative course between 1998 and 2020. We also conducted a chart review of our electronic medical record for conjoined twin separations between January 2015 and December 2019. Results: We report two cases of conjoined twin separation with preoperative use of 3DP models from our institution: one set in the thoracoomphaloischiopagus orientation and the other set in the thoracoomphalopagus orientation with the presence of intrahepatic vascular anomalies. The literature review produced 10 case reports of conjoined twin separation with use preoperative 3D models accounting for 17 individual separation procedures. We summarize our preoperative radiological planning, the evidence of 3DP models as an educational and preoperative tool, ideal timing for separation, and our surgical approach for complex hepatic separation. Conclusions: Conjoined twin separation requires a multidisciplinary effort to address the multisystem surgical and medical needs of these patients. These complex patients require extensive preoperative imaging for planning separation, and we strongly recommend utilizing 3D printed models when possible for better surgeon understanding of complex variable anatomy. We have found numerous reports of successful conjoined twin separation using 3DP technology in preoperative planning. The use of three-dimensional printed models for preoperative assessments is an invaluable tool and is rapidly improving in fidelity. Type of study: Operative technique and case series. (C) 2020 Elsevier Inc. All rights reserved.