Bones of the Cranium & Orbit Flashcards
Cranium
What are the parietal (2) bones?
They form roof and sides of cranium
They articulate with each other at the midline
They articulate with the frontal bone anteriorly and the occipital bone posteriorly
Cranium
What is the occipital bone?
Forms the posterior aspect of the skull and the posterior floor of the orbital cavity
They articulate with temporal, parietal and sphenoid bones
Cranium
What are the temporal bones?
Forms the side of the cranium (squamous portion)
Houses middle/inner ear structures
Articulates with the parietal, sphenoid bones, occipital and zygomatic bone
Cranium
What is the frontal bone?
Forms the anterior portion of the cranium and anterior floor of orbital cavity
Cranium
What is the sphenoid bone?
Forms the base of the cranium and lateral walls of the orbital cavity
It is composed of the body, lesser wings and greater wings
What structures are involved in the sphenoid bone?
Sphenoid body - Hypophyseal fossa (Pituitary gland)
Gap between the lesser wing and sphenoid body - optic canal (optic nerve exits orbit)
What is the supraorbital margin?
Where the frontal bone sits
It allows passage of the supraorbital neurovascular bundle
What is the infraorbital margin?
contains the zygomatic bone (laterally)
maxillary bone (medially)
has the infraorbital foramen
What is found in the lateral (temporal) margin?
Frontal bone - zygomatic process
Zygomatic bone - frontal process
What is the optic canal?
It is found within the lesser wing of the sphenoid
It is also where the optic nerve exits and ophthalmic artery enters
What is the superior orbital fissure?
gap between lesser and greater wings of the sphenoid
Transmits most other vascular and neural structures into the orbit
Attachment point for LR
What is the inferior superior orbital fissure?
Greater wing of the sphenoid and maxilla
It is a passage between the orbit and the emporak fossae
What are paranasal sinuses?
Cavities within the bone of the face
- filled with air
- lighten the skull
- help voice resonate
- drain mucus secretions
What is the superior sinus?
Known as the frontal sinus
What is the inferior sinus?
Known as the maxillary sinus