Jonathan Morris MD, Neuroradiologist, Mayo Clinic
Transoral robotic surgery using the FK retractor system is increasingly being used to maximally retract the jaw and soft tissues allowing robotic access to the base of the tongue to resect base of tongue tumors. During retraction the lingual artery is displaced. However, there have been no anatomic studies to date to determine where and how far. We provide a novel way to study this by retro engineering the FK retractor system using surface scanning and 3D printing. After IRB approval we surface scanned the FK retractor system and all tongue blades. The components of the retractor system were thickened to add structural stability then printed using fused deposition modeling and PC ISO. Six cadaver carotid arteries were injected with barium-laced silicone bilaterally. We then placed the 3D printed retractors into the cadavers oral cavity and then scanned them with the tongue blade neutral, right and left. 3D reconstructions were made in MIMICS and 3-Matic of the vascular anatomy. This allowed us to CT scan cadavers in the retracted position showing crucial vasculature anatomy a surgeon would encounter in TORS. This would not have possible without 3D printing the parts in a radiopaque material due to the metal artifact encountered in CT scanning. This study provides crucial information to the surgeon about danger zones where the lingual arteries have been displaced when the FK retractor system is used.