Abstract
Purpose :
Improper orbital implant placement is the most common cause of revision surgery and complications in orbital fracture repair. Ensuring correct orientation of the posterior aspect of the implant in the orbital apex in complex blowout and more extensive craniofacial fractures (ZMC, LeForte) is particularly critical. Once a cantilevered implant is provisionally anchored to the inferior orbital rim, it can also be challenging to adjust implant angulation. We demonstrate a method of intra-operative navigation utilizing a novel instrument that clamps onto a titanium mesh floor/medial wall implant and registers with a surgical navigation system to facilitate optimal positioning with respect to the orbital apex.
Methods :
An orbital floor/medial wall titanium mesh implant was positioned into a novel clamping instrument probe that was subsequently registered by the surgical navigation system, into which a CT maxillofacial scan of a man who suffered left ZMC fracture was imported. The navigable instrument was used to manipulate the implant within the orbital floor of the sterolithographic model skull with real-time feedback of the implant’s position within the orbital apex via automatic symmetrical visualization with the radiographic overlay (Figures 1-2).
Results :
The navigable instrument successfully aided simulated intra-operative positioning of the implant with continuous verification of the implant’s exact position within the orbital apex. This demonstration illustrated that instrument-guided navigation facilitates implant manipulation and real-time visualization of placement, allowing the surgeon to assess for deviations and adjust accordingly for optimal placement.
Conclusions :
Intra-operative instrument-guided navigation of orbital implants presents a significant advantage in improving implant positioning in orbital fracture reconstructions. This novel instrument facilitates both manipulation of implant angulation and orientation once provisionally placed as well as guidance to ensure optimal orientation.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.