Endoscopic endonasal transclival transodontoid approach

Corecha Santos et al. describe and evaluate the steps required to perform a combined endoscopic endonasal/transoral transclival transodontoid approach for anterior decompression of the craniovertebral junction.

The endoscopic endonasal transclival transodontoid approach combined with endoscopic transoral decompression was performed on 4 cadaveric specimens. Evaluation of this combined technique; a review of the literature; and the nuances, advantages, and pitfalls are reported.

Adequate wide anterior decompression was achieved in all specimens. This combined approach allowed the preservation of the anterior arch of C1 without injuring the eustachian tube anatomy and avoiding internal carotid artery manipulation.

Mastery of both techniques allows for a safe and comfortable surgical corridor. The transoral and transnasal approaches should not be considered as either/or techniques, but rather as a complement to each other. However, as with all new or developing techniques, there is a steep learning curve, which requires ample training in the skull base laboratory 1).


Recent advances in surgical techniques have rendered the craniocervical junction (CCJ) accessible transnasally. Endoscopic endonasal transclival and transodontoid approaches are routinely performed in leading skull base centers. Usually, these approaches involve a posterior bony and mucosal septectomy, which may compromise the vascularized pedicled nasoseptal flap (PNSF), a robust reconstructive option for repair of large skull base defects. With the possibility of an intraoperative cerebrospinal fluid leak and the reported success of the PNSF for repair of these defects, preserving the integrity of the PNSF is beneficial during the endoscopic endonasal approach to the CCJ. We describe three new variations/refinements of the endoscopic endonasal approach to the CCJ that preserve the mucosal integrity of the posterior nasal septum and PNSF.

Methods: Photo and video documentation of cadaveric dissections.

Results: The steps required for the different variations in approaching the CCJ are demonstrated. These three options are: 1) nonopposing Killian incisions with submucosal elevation of PNSFs laterally under the inferior turbinates (the PNSFs are retracted laterally and left attached superiorly onto the nasal septum and laterally under the inferior turbinate); 2) bilateral non-opposing PNSFs tucked beneath their respective middle turbinate or into the sphenoid sinus; and 3) a hybrid approach combining option 1 performed on one side and option 2 on the contralateral side. All three options allowed for a mucosal-sparing septectomy to provide ample access to the CCJ.

Conclusion: These variations/refinements of the mucosal-sparing approach to the CCJ allowed adequate surgical access with sufficient maneuverability while preserving both PNSFs 2)

1)
Corecha Santos R, Santiago RB, Gupta B, Dabecco R, Kaye B, Obrzut M, Adada B, Velasquez N, Borghei-Razavi H. Anatomical Description and Literature Review of the Endoscopic Endonasal Transclival Transodontoid Approach Combined with Endoscopic Transoral Decompression to the Anterior Craniovertebral Junction: A New Strategy. World Neurosurg. 2023 Jul;175:e151-e158. doi: 10.1016/j.wneu.2023.03.044. Epub 2023 Mar 16. PMID: 36931342.
2)
Eloy JA, Vazquez A, Marchiano E, Baredes S, Liu JK. Variations of mucosal-sparing septectomy for endonasal approach to the craniocervical junction. Laryngoscope. 2016 Oct;126(10):2220-5. doi: 10.1002/lary.25858. Epub 2016 Feb 18. PMID: 26891223.