Inferior Orbital Fissure Flashcards

Explore the inferior orbital fissure's bony boundaries, neurovascular contents, communications, anatomical relationships, and clinical significance.

Card 1 of 22Question

What is the inferior orbital fissure?

An elongated opening in the posterior orbit between the orbital floor and lateral wall.

In This Section

1. What is the inferior orbital fissure?

An elongated opening in the posterior orbit between the orbital floor and lateral wall.

2. Where is the inferior orbital fissure located?

In the posterolateral orbital floor, inferior to the superior orbital fissure.

3. Which bones form the principal boundaries of the inferior orbital fissure?

The maxilla and greater wing of the sphenoid bone.

4. Which bones contribute to the lateral and medial ends of the inferior orbital fissure?

The zygomatic bone laterally and the palatine bone medially.

5. Which surface of the maxilla forms the inferior boundary of the fissure?

The orbital surface of the maxillary body.

6. Which part of the sphenoid forms the superior boundary of the fissure?

The orbital surface of the greater wing.

7. Which two extracranial fossae communicate with the orbit through the inferior orbital fissure?

The pterygopalatine and infratemporal fossae.

8. Which region communicates with the medial part of the inferior orbital fissure?

The pterygopalatine fossa.

9. Which region communicates with the lateral part of the inferior orbital fissure?

The infratemporal fossa.

10. Which two major sensory nerves enter the orbit through the inferior orbital fissure?

The infraorbital and zygomatic nerves.

11. From which cranial nerve division do the infraorbital and zygomatic nerves originate?

The maxillary division of the trigeminal nerve (cranial nerve V2).

12. Where does the infraorbital nerve travel after entering the orbit?

Along the infraorbital groove and canal in the orbital floor.

13. Through which opening does the infraorbital nerve leave the orbit and emerge onto the face?

The infraorbital foramen.

14. Which sensory regions are supplied by the terminal branches of the infraorbital nerve?

The lower eyelid, lateral nose, cheek, and upper lip.

15. What is the course of the zygomatic nerve after entering the orbit?

It travels along the lateral orbital wall and divides into zygomaticofacial and zygomaticotemporal branches.

16. Which artery enters the orbit through the inferior orbital fissure?

The infraorbital artery, a branch of the maxillary artery.

17. Which vein may pass through the inferior orbital fissure?

The inferior ophthalmic vein, or a communicating branch connecting it with the pterygoid venous plexus.

18. Which autonomic nerve branches may enter the orbit through the inferior orbital fissure?

Orbital branches associated with the pterygopalatine ganglion.

19. What is the relationship between the inferior orbital fissure and the maxillary sinus?

The fissure lies near the posterior orbital floor, immediately superior to the maxillary sinus.

20. How does the inferior orbital fissure differ from the superior orbital fissure in its cranial nerve contents?

It transmits branches of V2, whereas the superior orbital fissure transmits nerves III, IV, V1, and VI.

21. Why can an orbital floor fracture cause sensory loss in the infraorbital nerve distribution?

Fracture displacement or swelling may compress the infraorbital nerve near the fissure, groove, or canal.

22. What is the clinical significance of the venous connections through the inferior orbital fissure?

They provide a potential route for infection to spread between the infratemporal region and orbital venous system.