Transorbital Endoscopic Approach to the Sylvian Fissure

The transorbital endoscopic approach using an eyelid incision has been proposed as a new minimally invasive technique for the treatment of skull base pathology. A superior eyelid incision followed by orbital retraction provides a surgical window for exposure of the skull base. The superior (SOF) and inferior (IOF) orbital fissures represent the medial limits of the approach and are identified in the initial part of the procedure. Drilling of the orbital roof (lateral and superior to the SOF), greater sphenoidal wing (lateral to the SOF and IOF) and lesser sphenoidal wing expose the anterior and middle fossa dura. A square-shaped dural opening provides visualization of the posterior orbital gyri, sylvian fissure and temporal pole. Intradural dissection allows exposure of the sphenoidal portion of the sylvian fissure, M1, MCA bifurcation and M2 branches and lenticulostriate perforators. This approach can be applied for clipping of proximal MCA aneurysms and management of tumors with extension to the sylvian fissure, as single corridor or in combination with other skull base approaches.