Technical Nuances of Combined Endoscopic Trans-Nasal and Trans-Facial Approach to Pterygopalatine Fossa: Highlighting the Merits of the Endoscopic Trans-Facial Anterior Maxillary Approach to the Infra-Temporal Fossa

Introduction: Pathologies in the pterygopalatine and infratemporal fossa are very challenging for a skull base surgeon owing to its deep location and complexity of the approaches described to reach this area.

Endoscopic skull base approaches has been dramatically evolving during the past decade, offering minimally invasive access with better exposure and visualization to pathologies in such areas. Continuous refinement of endoscopic approaches has been taking place, allowing for expanding its capabilities and understanding its limits.

Combined endoscopic transnasal and transfacial approach to the pterygopalatine and infratemporal fossa is one example of such refinements.

Objectives: In this study, we will describe the technical nuances of combined endoscopic transnasal and transfacial approach to the pterygopalatine fossa using an illustrative case of a schwannoma extending to pterygopalatine fossa and maxillary sinus. We will highlight the advantages of endoscopic trans-facial anterior maxillary approach as a direct approach to the infra-temporal fossa.

Conclusion: We found the combined transnasal and transfacial approach very useful and helped us in the preservation of the middle turbinate, guarding the patient from the high incidence of atrophic rhinitis, given that the inferior turbinate was invaded by the tumor and was removed.

Endoscopic trans-facial anterior maxillary approach provides a minimally invasive access to the pterygopalatine & infra-temporal fossa. It allows direct access to the neural contents in the posterior-superior portion of the pterygopalatine fossa. It allows better access for vascular control & hemostasis, avoiding the menace of dealing with the vascular contents, which are at the anterior-inferior portion of the fossa. It also avoids unnecessary medial-inferior to lateral-superior dissection to reach the pterygopalatine & infra-temporal fossa encountered during endoscopic trans-nasal approach. It also provides great maneuverability of instruments either alone or combined with trans-nasal approach, with avoidance of use of angled instruments or scopes. It also improves the lateral reach to the infra-temporal fossa.

In our experience, we think the use of endoscopic trans-facial anterior maxillary approach may be feasible to be used as a stand-alone direct approach to the pterygopalatine & infra-temporal fossa & may provide significant advantages over the endoscopic trans-nasal approach.

Fig. 1 Endoscopic trans-facial view, using 0 degree lens, showing pterygopalatine fossa after resection of tumor. (Note the contents of pterygopalatine fossa (PPF) displaced laterally within its periosteal sheath)

Fig. 2 Endoscopic trans-nasal view, using 0 degrees lens, showing the pterygopalatine fossa after resection of tumor. (Note the limited lateral reach and visualization as compared with trans-facial route in (Fig. 1).