3:45 – 4:45 pm

Category: Art

Craniopagus Twin Separation Guided by Novel Virtual and Physical Pre-Surgical Simulation

Craniopagus twins, or twins conjoined at the cranium, have a very rare congenital anomaly, which occurs in one out of every ~2.5 million births. Separation, when feasible, requires a comprehensive team including neurosurgeons, plastic surgeons, anesthesiologists, and specialized nursing staff. This talk highlights how a medical illustrator can also be integrated into part of the surgical planning process, through a case presentation of a rare craniopagus twin separation. Craniopagus twin girls were identified on prenatal ultrasound at 11 weeks. Imaging and examination demonstrated connection of the scalp, calvaria, and dura, as well as a venous fistula. A robust multidisciplinary team was involved with extensive pre-surgical planning. Months prior to the separation, the Plastic Surgery team designed a novel wedge-shaped tissue expander, which was placed to ensure sufficient skin coverage, as separation would otherwise leave each twin with a soft tissue defect. Once expanded, novel virtual and physical soft tissue modeling methods were employed using CT data to (1) quantify the anticipated soft tissue deficits for each twin following cranial separation, and (2) subsequently verify sufficiently expanded scalp tissue to address these defects. 3D virtual modeling was then further leveraged to facilitate precise skin incision planning. Finally, physical soft tissue models were 3D printed, which were incised and inset based on the virtual design to physically verify the simulations, allowing surgeons to practice and refine the incision design before ever setting foot in the operating room. The proposed outline from the models ultimately led to an optimal surgical outcome. At 10 months of age, the twins underwent cranial separation and successful soft tissue coverage using only native expanded scalp.

Session Takeaways:
1. Utilize 3D models generated from CT scans to calculate soft tissue surface area for planning surgical incisions
2. Collaborate with a multidisciplinary surgical team to solve complex surgical problems


Sarah Chen, MD

Cardiothoracic Surgery Resident, UC Davis Medical Center

Sarah Chen is currently a Cardiothoracic Surgery resident at UC Davis. She took a hiatus from her studies while at UC Davis School of Medicine to pursue an MA in medical illustration at Johns Hopkins. After finishing her master’s degree, she returned to complete her MD, and subsequently began her surgical residency. She is intent on strengthening the collaboration between medical illustration and medical/surgical education. She is particularly passionate about utilizing her medical illustration background to augment patient education and to improve pre-surgical planning. She is enamored with the color red, and can been seen in clinic sporting her red hair, red nails, and bright red stethoscope.