Lesser Wing Of The Sphenoid Bone, Superior View

Description

Lesser wing of the sphenoid (ala minor) occupies the anterior cranial base, projecting laterally from the sphenoid body and forming a sharp sphenoidal ridge that separates the anterior cranial fossa superiorly from the middle cranial fossa inferiorly. In superior view, the smooth endocranial surface of the ala minor lies anterolateral to the sella turcica region and medial to the greater wing, with its posterior free margin contributing to the superior boundary of the superior orbital fissure. Medially, the wing’s root approaches the optic canal, while laterally it thins toward the orbital plate that will form part of the orbital roof. A crisp bony landmark. Clinically, the ala minor matters because its medial end is continuous with the anterior clinoid process, a key reference point in skull base surgery and in interpreting fractures that extend across the sphenoid ridge into the orbit. Lesions involving the optic canal, such as sphenoid wing meningioma or traumatic optic neuropathy, are often discussed in relation to the lesser wing’s root and the adjacent optic strut, so a superior perspective helps orient the canal’s location relative to the anterior cranial fossa floor. Subtle changes in contour along the sphenoidal ridge also guide readers when correlating dry skull anatomy with CT of the anterior skull base and orbital apex. Neuroanatomy and head and neck anatomy courses can pair this illustration with cranial fossa maps, optic canal diagrams, and superior orbital fissure content to reinforce boundaries students commonly confuse. Medical publishers will find it well suited for atlas plates on the sphenoid bone, anterior clinoid process, and orbital roof, and for surgical education materials describing pterional or orbitocranial approaches where the lesser wing is a first encountered landmark. Anatomical accuracy verified by SciePro's Medical Advisory Board.