Virtual splint registration for electromagnetic and optical navigation in orbital and craniofacial surgery

Abstract

In intra-operative navigation, a registration procedure is performed to register the patient’s position to the pre-operative imaging data. The registration process is the main factor that determines accuracy of the navigation feedback. In this study, a novel registration protocol for craniofacial surgery is presented, that utilizes a virtual splint with marker points. The accuracy of the proposed method was evaluated by two observers in five human cadaver heads, for optical and electromagnetic navigation, and compared to maxillary bone-anchored fiducial registration (optical and electromagnetic) and surface-based registration (electromagnetic). The results showed minimal differences in accuracy compared to bone-anchored fiducials at the level of the infra-orbital rim. Both point-based techniques had lower error estimates at the infraorbital rim than surface-based registration, but surface-based registration had the lowest loss of accuracy over target distance. An advantage over existing point-based registration methods (bone-anchored fiducials, existing splint techniques) is that radiological imaging does not need to be repeated, since the need for physical fiducials to be present in the image volume is eradicated. Other advantages include reduction of invasiveness compared to bone-achnored fiducials and a possible reduction of human error in the registration process.

Personalized Medicine Workflow in Post-Traumatic Orbital Reconstruction

“…Several registration methods are available: soft-tissue registration, bone-anchored fiducials, and surgical splints [56,58]. Splint registration methods used to require repeated radiographic imaging with the fiducial splint in place, but the fusion of intraoral scan data in the advanced diagnostics phase allows the fabrication of a registration splint without additional radiologic imaging [59]. The splint is designed on the individual patient's dentition and carries fiducials that can be indicated virtually in the planning software and physically in the OR.…”

Image-guided orbital surgery: a preclinical validation study using a high-resolution physical model

“…The accuracy of EM-IGS’s surface registration has been questioned in the past as the electromagnetic field is based on narrow field surface registration rendering the depth of orbit distant and that in turn can affect accuracy of navigation, although evidence suggests surface registration is superior to point or fiducial based registration in related anatomical areas 12 13. There is additional interference with ferromagnetic instruments and devices thereby theoretically making the navigation less accurate.…”

Computer-Aided Dynamics Intraoperative Navigation in Oral Medicine: A Review

“…The monitor is used to display real-time medical images and navigation images for the physician. The location tracking system is used to perform the registration procedure to compose the patient's position into the preoperative imaging data, and the registration process is the main factor that determines the accuracy of the navigation feedback (Schreurs et al 2021b). According to the working principle of the location tracking system, it can be divided into optical location tracking and electromagnetic location tracking.…”