Mini Fronto-Orbital Approach: "Window Opening" Towards the Superomedial Orbit - A Virtual Reality-Planned Anatomic Study.

Abstract

Surgical approaches to the orbit are challenging and require combined multispecialist skills. Considering its increasing relevance in neurosurgical practice, keyhole surgery could be also applied to this field. However, mastering a minimally invasive approach necessitates an extended learning curve. For this reason, virtual reality (VR) can be effectively used for planning and training in this demanding surgical technique. To validate the mini fronto-orbital (mFO) approach to the superomedial orbit, using VR planning and specimen dissections, conjugating the principles of skull base and keyhole neurosurgery. Three-dimensional measurements were performed thanks to Surgical Theater (Surgical Theater© LLC), and then, simulated craniotomies were implemented on cadaver specimens. The mFO approach affords optimal exposure and operability in the target area and reduced risks of surrounding normal tissue injuries. The eyebrow skin incision, the minimal soft-tissue retraction, the limited temporalis muscle dissection and the single-piece craniotomy, as planned with VR, are the key elements of this minimally invasive approach. Furthermore, the "window-opening" cotton-tip intraorbital dissection technique, based on widening surgical corridors between neuromuscular bundles, provides a safe orientation and a deep access inside the orbit, thereby significantly limiting the risk of jeopardizing neurovascular structures. The mFO approach associated to the window-opening dissection technique can be considered safe, effective, suitable, and convenient for treating lesions located in the superomedial orbital aspect, up to the orbital apex.