The Use of Intraoperative Navigation for Percutaneous Procedures at the Skull Base Including a Difficult-to-Access Foramen Ovale

BACKGROUND: We describe the use of an intraoperative CT scan obtained using the Medtronic O-arm (Littleton, Massachusetts) for image-guided cannulation of the foramen ovate not previously accessible with the use of fluoroscopy alone. Unlike previously described procedures, this technique does not require placement of an invasive head clamp and may be used with an awake patient. OBJECTIVE: To describe the use of intraoperative neuronavigation for accessing skull base foramina and, specifically, cannulating of the foramen ovale during percutaneous rhizotomy procedures using an intraoperative image guidance CT scanner (Medtronic O-arm, Littleton, Massachusetts). METHODS: A noninvasive Landmark Fess Strap attached to a spine reference frame was applied to the heads of 4 patients who harbored a difficult-to-access foramen ovate. An intraoperative HD3D skull base scan using a Medtronic O-arm was obtained, and Synergy Spine software was used to create 3D reconstructions of the skull base. Using image guidance, we navigated the needle to percutaneously access the foramen ovale by the use of a single tract for successful completion of balloon compression of the trigeminal nerve. RESULTS: All 4 patients (3 females and 1 male; ages 65-75) underwent the procedure with no complications. CONCLUSION: Based on our experience, neuronavigation with the use of intraoperative O-arm CT imaging is useful during these cases.