Chiasmatic groove

Groove whose anterior border is a ridge bounding the sphenoid bone

The chiasmatic groove is a transverse groove upon the superior aspect of the body of sphenoid bone within the middle cranial fossa. It is bounded anteriorly by the sphenoidal limbus, and posteriorly by the tuberculum sellae. The opening of each optic canal is placed at either lateral end of the chiasmatic sulcus. The optic chiasm is situated superior and quite posterior to the chiasmatic groove.

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