Skull Landmarks & Cranial Fossae Flashcards
1. Identify anterior skull landmarks 2. Identify major lateral skull landmarks 3. Identify major posterior skull landmarks 4. Identify external cranial fossae and their boundaries 5. Identify internal cranial fossae and their boundaries
Superciliary arches are more prominent in (males or females)
males
Prominent aspect of frontal bone, underlying the eyebrow
Superciliary arches
Smooth, slightly depressed and between the superciliary arches
Glabella
Point of fusion of frontal suture that is present only in infants
Glabella
Intersection between frontal and nasal bones
Nasion
Bridge of nose
Nasion
Triangularly bony elevation formed by fusion of two halves of mandible
Mental Protuberance (this is where butt chins are)
Prominence of the chin
Mental Protuberance
Shallow depression on lateral aspects of skull
Temporal Fossa
Bounded by: superior temporal line, inferior temporal line, frontal bone, zygomatic bone, zygomatic arch
Temporal fossa
Contains the Pterion
Temporal Fossa
Irregular space inferior and deep to the zygomatic arch and the ramus of the mandible located posterior to the maxilla
Infratemporal Fossa
The Infratemporal Fossa contains important _____ structures
Neurovascular
External opening into the auditory canal
External Acoustic Meatus
Sit of muscle attachment (sternocleidomastoid and posterior belly of the digastric)
Mastoid Process of Temporal Bone
Sit of muscle attachment (stylohyoid muscle)
Styloid Process of Temporal Bone
Formed by the zygomatic process of the temporal bone and the temporal process of the zygomatic bone, which are united by the zygomaticotemporal suture
Zygomatic Arch AKA CHEEKBONE
H-shaped formation of sutures that unite the frontal, sphenoid, temporal, and parietal bones
Pterion (where someone would normally hold the gun to their head if they wanted to shoot themselves)
Vulnerable to fracture from blunt trauma. Overlies middle meningeal artery on its internal surface, which can lead to epidural hematoma in cases of trauma
Pterion
Prominence of bone at the center of the occipital bone
External occipital protuberance
Overlies the confluence of sinuses, which is located internal to the bone
External Occipital protuberance
Shallowest and most elevated of the three cranial fossae
Anterior cranial fossa
Contains the anterior parts of the frontal lobes of the brain
Anterior Cranial Fossa
What 3 bones form the Anterior Cranial Fossa?
Frontal Bone (ant) Ethmoid Bone (med) Body of the Sphenoid and Lesser Wings of the Sphenoid (post)
Median bony extension of the frontal bone that contains Foramen Cecum
Frontal Crest of Anterior Cranial Fossa
This ridge of bone that projects superiorly from ethmoid bone
Crista Galli of ethmoid bone
Perforated by many small foramina to allow passage of the olfactory nerves into the nasal cavity
Cribiform Plate
Separated from the anterior cranial fossa by the sphenoidal crests, which are formed by the posterior borders of the lesser wing of the sphenoid bone
Middle Cranial Fossa
Bounded posterior by the superior border of the petrous part of the temporal bone
Middle Cranial Fossa
Composed of the greater wings and body of the sphenoid bone, part of the temporal bone and part of the parietal bone
Middle Cranial Fossa
Allow for the exit of many neurovascular structures
Middle Cranial Fossa
Supports the temporal lobes of the brain
Middle Cranial Fossa
Largest and deepest of the 3 cranial fossae
Posterior Cranial Fossa
Contains the cerebellum, pons, and medulla oblongata
Posterior Cranial Fossa
Formed mostly by the occipital bone, with small contributions by the temporal and parietal bones
Posterior Cranial Fossa
