Expanding horizons: the feasibility and challenges of tubular retraction in endoscopic transorbital skull base approaches.

Abstract

Purpose: Endoscopic transorbital skull base approaches are always challenging and require good anatomical knowledge.The aim of this study was to describe the anatomical pathways of endoscopic transorbital approaches and to determine the limitations of these procedures. To evaluate the feasibility of the tubular retractor and the difference with manual retractor.

Methods: The targets of endoscopic transorbital approach were the anterior and middle cranial fossa, mesial temporal region, meckel's cave, petroclival area, opticocarotid region, anterior and lateral walls of the cavernous sinus, etc. Step-by-step anatomical dissections were performed in cadaveric heads using manual and tubular retractors.

Results: Anterior and middle cranial fossa was reached. The branches of the trigeminal nerve, the lateral wall of the cavernous sinus, meckel's cave and gasserian ganglion were exposed by manual and tubular retraction using an endoscopic transorbital approach. Access to the temporal horn of the lateral ventricle and the mesial temporal region was more accessible with a tubular retractor. Also, following the anterior clinoidectomy, the cavernous segment of the internal carotid artery, as well as, the arteries of the anterior circulation were exposed to gain access the vascular skull base lesions.

Conclusion: The endoscopic transorbital approach is suitable for the surgical treatment of many pathologies located in the anterior and middle skull base. It provides direct access to vascular and tumoral lesions. We observed that mesial temporal region interventions are possible with this approach. The transtubular technique may have some limitations, but in selected cases it can provide clear vision without brain retraction.