N1 Skull meninges dural venous sinuses

What is the main to parts of the skull?

Neurocranium (cranial vault), viscerocranium (facial skeleton)

What is the neurocranium?

The bony case that protects the brain, meninges, cranial meninges, proximal parts of cranial nerves, and brain vasculature

What and how many bones form the neurocranium?

8 bones, frontal, ethmoid, sphenoid, occipital, temporal(2), parietal(2)

What and how many bones form the viscerocranium?

15 bones, mandible, ethmoid, vomer, maxilla(2), inferior nasal concha(2), zygomatic(2), palatine(2), nasal(2), and lacrimal(2)

Which bone forms the lower jaw?

Mandible

Which bones form the upper jaw?

Maxillae

Which bones form the cheekbones?

Zygomatic bones

Which bone forms the forehead?

Frontal bone

Which bones form the superior and lateral parts of the skull?

Parietal bones

Which bones contain the external auditory meatus?

Temporal bones

What is the orbit?

The bony part of the skull that contains and protects the eyeball and associated structures

What is the supraorbital notch or foramen?

The superior margin of the orbit formed by the frontal bone, can be a notch or foramen when it is completely enclosed by bone

What is the infraorbital foramen?

The inferior part of the orbital and is it an opening of the maxilla

What is the mental foramen?

An opening of the mandible that is inferior to the second premolar teeth

What is in the temporal bone?

external auditory meatus, mastoid process, styloid process, zygomatic process

What is in the occipital bone?

external occipital protuberance

What is the orbitomeatal plane?

the inferior margin of the orbit and superior to the external auditory meatus on both sides in the same horizontal plane

What are the sutures in the skull?

coronary, saggital, squamous, lambdoid

What do the coronary sutures do?

seperates frontal from 2 parietal

What does saggital sutures do?

seperates two parietals,

What do the squamous sutures do?

seperates parietal from temporal

What do the lambdoid suture do?

separates the parietal from the occipital

What are the three large depressions of the internal surface of the cranial surface?

anterior, middle, and posterior cranial fossae, form a bowl shape

Where is the anterior, middle, posterior fossa relatively at?

frontal lobe, temporal lobe(sphenoid/ethmoid), cerebellum(occipital/ethmoid)

What does the anterior fossa contain?

crista gali

What does the middle fossa contain?

superior orbital fissure, foramen rotundum, foramen ovale

What does the posterior fossa contain?

internal acoustic meatus, jugular foramen, foramen magnum, hypoglossal canal

Where are the structures in the middle fossa in the sphenoid ?

superior orbital fissures, foramen rotundum, foramen ovale

What structures are in the posterior fossa in the ethmoid?

internal acoustic meatus, jugular foramen

What are the three layers of the cranial meninges? deep to superficial

pia matter, arachnoid matter, dura mater

what to layers are in the dura mater, deep to superficial

meningeal layer, periosteal layer, loose connective tissue

What are the dural infoldings?

folds formed by the meningeal layer of the dura that is separated from the periosteal layer

What is the other name for dura infoldings?

dural reflections or dural septa

What is the dural venous sinuses?

endothelial-lined spaces between the periosteal and meningeal layers of the dura

what are the leptomenings?

Arachnoid mater(meningeal layer) and pia mater(cerebral cortex), both below dura mater

What is in between arachnoid and pia mater?

subarachnoid space, filled with cerebrospinal fluid

What are arachnoid granulations/villus?

Tufted projection of a collection of arachnoid villi into the superior sagittal venous sinus, protruding from the meningeal layer.

What is the function of arachnoid granulations/villus?

transfer cerebrospinal fluid (CSF) to the venous system

What is included in dural septa?

falx cerebri, flax cerebelli, and tentorium cerebelli

What is the falx cerebri?

The largest dural infolding that is sickle-shaped lies in the longitudinal cerebral fissure

What is falx cerbelli?

continues inferiorly and posteriorly to the flax cerebri, runs along the vermis of the cerebellum

What is tentorium cerebelli?

almost horizontal and the transverse fissure between the cerebral hemisphere and the cerbellum

The major dural venous sinuses

sigmoid, right/left transverse, confluence, falx cerebri, tentorium, straight, superior sagittal, inferior sagittal