Which bone forms the superior orbital fissure?

Which bone forms the superior orbital fissure?

• A. Sphenoid bone only
• B. Maxilla
• C. Frontal bone
• D. Zygomatic bone

Answer: (A)

The superior orbital fissure is formed by the sphenoid bone, specifically by its lesser and greater wings forming the boundary between the middle cranial fossa and the orbit. This gap is what lets important structures pass from the cranial cavity into the eye orbit—cranial nerves III, IV, V1 (ophthalmic branch), and VI, along with the superior ophthalmic vein. The frontal bone, maxilla, and zygomatic bone shape parts of the orbit’s walls, but they do not create this fissure. That’s why the sphenoid is the bone responsible for forming the superior orbital fissure.

The superior orbital fissure is formed by the sphenoid bone, specifically by its lesser and greater wings forming the boundary between the middle cranial fossa and the orbit. This gap is what lets important structures pass from the cranial cavity into the eye orbit—cranial nerves III, IV, V1 (ophthalmic branch), and VI, along with the superior ophthalmic vein. The frontal bone, maxilla, and zygomatic bone shape parts of the orbit’s walls, but they do not create this fissure. That’s why the sphenoid is the bone responsible for forming the superior orbital fissure.