Intracranial Anatomy Flashcards
Neurocranium Components
Cranial vault and cranial base
Cranial vault
- Calvaria or membranous neurocranium
- Develops from intramembranous ossification
Cranial base
- Basicranium or chondral neurocranium
- Develops from endochondral ossification
Viscerocranium
- Face and mandible
- Develops from branchial arches
Types of bone in cranial vault
- Compact bone of inner and outer tables
- Diploë: spongy bone in the middle
Cranial Sutures
- Fibrous joint: held together by Sharpey’s fibers (collagen type III)
- Sutural (Wormian) bones: small, irregular bones that develop within sutures
Cranial vault sutures
- Coronal
- Lambdoid
- Metopic/frontal (fuses at 9 months)
- Pterion
- Sagittal
- Squamosal
Facial (palatal) sutures
- Intermaxillary
- Transverse palatine
Emissary veins
External veins that drain through diploic veins to internal dural sinuses. These are a potential route of infection from the scalp into the cranial vault.
Cranial sinuses
- Frontal
- Ethmoidal
- Sphenoidal
- Maxillary (Antrum)
Also: mastoid air cells
Semilunar hiatus
Drains frontal, maxillary, and anterior ethmoidal sinuses into nasal cavity
Posterior ethmoidal and sphenoidal sinuses drain into…
nasopharynx
Maxillary Sinus (Antrum)
- contains the CN V2, maxillary nerve (GSA to upper teeth, palate, nasal cavity)
- Maxillary dental roots can project into sinus
Meninges from Superficial to Deep
- Dura mater
- Arachnoid mater
- Pia mater
Arterial supply to meninges
middle meningeal artery from maxillary artery
Innervation of meninges
- anterior and middle cranial fossae- CN V
- Posterior cranial fossa- CN IX, X C1-3