Intraconal Anatomy of the Anterior Ethmoidal Neurovascular Bundle: Implications for Surgery in the Superomedial Orbit

Lifeng Li, Nyall R. London, Daniel M. Prevedello, Ricardo L. Carrau

Research output: Contribution to journalArticle


Background: The anterior ethmoidal artery (AEA) branches from the ophthalmic artery in the superomedial intraconal space. The feasibility of management of lesions arising from the superomedial intraconal space via an endoscopic endonasal approach has not been sufficiently explored. Objective: To yield a detailed anatomic description of the anterior ethmoidal neurovascular bundle and its variants to serve as the foundation for possible management of lesions in the superomedial intraconal space. Methods: Eight cadaveric specimens (16 sides) were dissected using an endonasal approach, tracing the AEA proximally through the superomedial intraconal space. Furthermore, the anatomy of adjacent structures was noted, and distances from the anterior ethmoidal foramen to the origin of the AEA at the ophthalmic artery were measured. Results: Supraorbital cells were found in 13/16 sides (81.25%), and a bony dehiscence of the anterior ethmoidal canal was observed in 5/16 sides (31.25%). The nasociliary nerve, ophthalmic artery, superior division of the oculomotor nerve, superior rectus muscle, and levator palpebrae superioris were routinely identified in the superomedial intraconal space. The AEA passed through a corridor between the medial rectus and superior oblique muscles after arising from the ophthalmic artery (lateral to the foramen) in all specimens. The average distance from its origin to the anterior ethmoidal foramen was 5.19 ± 0.98 mm. Conclusion: Anatomically, it is feasible to access the superomedial intraconal space via an endoscopic endonasal approach. This study provides the anatomical basis for procedures in the superomedial intraconal space.

Original languageEnglish (US)
Pages (from-to)394-400
Number of pages7
JournalAmerican Journal of Rhinology and Allergy
Issue number3
StatePublished - May 1 2020



  • anterior ethmoidal artery
  • intraconal space
  • medial rectus muscle
  • superior oblique muscle
  • supraorbital cell

ASJC Scopus subject areas

  • Immunology and Allergy
  • Otorhinolaryngology

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