Anatomy of the Bony Orbit

Introduction

• Presenter: Peter from Anatomy Zone
• Collaboration: Anatomy Zone and Teach Me Anatomy
• Focus: Anatomy of the Bony orbit (eye sockets)

Structure of the Bony Orbit

• Description: Bilateral, symmetrical cavities in the head.
• Function: Encloses the eyeball and associated structures.
• Shape: Pyramidal structure
  • Apex: Points posteromedially into optic foramen.
  • Base: Anteriorly opens up into the face, formed by the orbital rim.

Bones Forming the Orbit

Anterior View

• Frontal Bone: Red
• Maxilla: Purple
• Zygomatic Bone: Light Blue
• Sphenoid Bone: Yellow (posteriorly)
• Ethmoid Bone: Orange

Medial Aspect

• Lacrimal Bone: Green
• Ethmoid Bone: Orange
• Palatine Bone: Dark Blue

Boundaries of the Orbital Rim

• Superior Border: Frontal bone
• Medial Border: Frontal process of the maxilla
• Inferior Border: Zygomatic process of the maxilla and zygomatic bone
• Lateral Border: Frontal process of the zygomatic bone and zygomatic process of the frontal bone

Components of the Bony Orbit

Roof/Superior Wall

• Formed by the frontal bone and lesser wing of the sphenoid
• Separates orbit from the anterior cranial fossa

Floor/Inferior Wall

• Formed by maxilla, palatine, and zygomatic bones
• Separates orbit from maxillary sinus

Medial Wall

• Formed by ethmoid, maxilla, lacrimal, and sphenoid bones
• Separates orbit from ethmoid sinus

Lateral Wall

• Formed by zygomatic bone and greater wing of sphenoid

Apex

• Located at the optic canal opening

Contents of the Bony Orbit

• Eyeballs and Associated Structures
  • Extraocular muscles
  • Eyelids
  • Nerves and blood vessels
• Nerves
  • Cranial Nerves: Optic, Oculomotor, Trochlear, Trigeminal, Abducens
• Blood Vessels
  • Opthalmic artery, superior and inferior opthalmic veins

Pathways into the Orbit

• Optic Canal: Transmits optic nerve and opthalmic artery
• Superior Orbital Fissure: Transmits several nerves and superior opthalmic vein
• Inferior Orbital Fissure: Transmits zygomatic branch of maxillary nerve, inferior opthalmic vein, sympathetic nerves

Additional Openings

• Nasolacrimal Canal: Drains tears to nasal cavity
• Supraorbital and Infraorbital Foramina: Transmit small neurovascular structures

Conclusion

• Anatomy of the bony orbit covers several bones, nerves, and pathways essential for eye function.
• Additional resources available on Anatomy Zone and Teach Me Anatomy.
• Video models powered by Anatomy Learning App.