The endoscopic prelacrimal recess approach to the paramedian middle cranial base: An anatomical study.

BACKGROUND

Endoscopic endonasal approach to paramedian cranial base implies sacrifice of the nasal structures.

OBJECTIVE

The present study aimed to illustrate the anatomy and provide critical anatomical landmarks for the endoscopic prelacrimal recess approach (PLRA) to the paramedian middle cranial base.

METHODS

Anatomical dissections were performed in 10 cadaveric specimens.

RESULTS

Successful access to the paramedian middle cranial base was achieved in all dissections via the PLRA with the removal of the pterygoid process. For the dissection of the infratemporal fossa and pterygopalatine fossa, the buccal nerve and infraorbital neurovascular bundle can serve as important anatomic landmarks to identify the detailed structures. In the upper parapharyngeal space, the stylopharyngeal aponeurosis can present as anatomical barriers to protect the parapharyngeal segment of the internal carotid artery (PPICA); while the levator veli palatini muscle can be considered as a landmark to locate the PPICA. For the dissection of the Eustachian tube (ET), the isthmus of the ET and ET sulcus can serve as useful landmarks to identify the posterior genu of the ICA and horizontal segment of the petrous ICA respectively.

CONCLUSION

The PLRA to the paramedian middle cranial base is anatomically feasible and can facilitate preservation of the integrity of nasal structures. The buccal nerve, infraorbital neurovascular bundle, levator veli palatini muscle, stylopharyngeal aponeurosis, the isthmus of the ET, and ET sulcus can serve as critical anatomic landmarks in their respective region and may facilitate the application of this approach.