2025 Poster Presentations
P045: TRANSORBITAL TRANSCAVERNOUS APPROACH: KEY STEPS AND ANATOMICAL LANDMARKS
Alhusain Nagm, MD, MSc, PhD; Department of Neurosurgery University of Maryland School of Medicine, Baltimore, MD, United States
Objective: Deliver a key step-by-step surgical guide for the microscopic trans-orbital trans-cavernous approach.
Background: A trans-orbital corridor is an alternative option for selected skull base/cavernous sinus pathologies, particularly when standard approaches are limited (ex. ipsilateral previous extracranial-intracranial vascular anastomosis for compromised internal carotid artery by the tumor). For those cases, a reasonable alternative approach is an indispensable prerequisite.
Methods: Twelve sides of 6 colored-injected embalmed heads, were examined to study the key surgical steps to the gulfer region of the cavernous sinus via a modified microscopic eyebrow transorbital approach. Anatomical targets (n= 14) were elected to identify the degree of adequate exposure, accessibility, and maneuverability. The data were collected and analyzed.
Results: The three stepwise-surgical phases (exposure/cavernous sinus unlocking/gulfer region dissection) allowing reasonable visual validation and maneuverability for all (n=168 (14 x 6 heads x 2 sides)) targets (subfrontal lobe, temporal pole, meningio-orbital band, middle meningeal artery, orbital apex, anterior clinoid process, optic nerve, oculomotor nerves, trochlear nerve, trigeminal nerve/ganglion, cavernous carotid artery/meningio-hypophyseal trunk, abducent nerve, Gruber’s ligament, and petrous apex). Besides, a step-by-step identification of key surgical landmarks defeats the tunnel-like corridor to the deepest targets, offers adequate maneuverability, and provides a precise landing at the gulfuer region of the cavernous sinus (Fig. 1-3). This extradural approach could be combined with intradural exposure to control extended tumors (Fig. 4). The current limit for this approach is the beyond Meckle’s Cave “trigeminal ganglion” opening (=inadequate microscopic visualization/maneuverability within the posterior fossa).
Conclusion: To ensure fruitful microscopic trans-orbital trans-cavernous surgery, our three stepwise surgical phases could be considered as a guide for surgeons. The key step-by-step dissection of specific surgical targets prepares an unrestricted corridor and provides reasonable maneuverability for the gulfuer region of the cavernous sinus.