cranium

bones of the neurocranium

frontal, parietal, occipital, temporal, sphenoid, ethmoid

Parietal bones joined by the

sagittal suture

is the most posterior bone

occipital bone

where muscles attach to the skull, a part of the occipital bone

superior nuchal lines, external occipital protuberance

Flat part of the temporal bone is the

squamous part

is the bump behind the ear, Attachment for sternomastoid muscle

mastoid process

is sharp protrusion close to the mastoid process

styloid process

is between frontal and parietal bones

coronal suture

sutures in the adult calvarium

coronal, sagittal, lambdoid

In the newborn infant the sutures are

flexible fibrous joints

fontanelles in the newborn

anterior and posterior

fontanelle that runs with the coronal suture, should close by the age of two

anterior fontanelle

fontanelle that runs with lambdoid suture, should close by 3-4 months of age

posteror fontanelle

forehead suture

metopic suture

Premature closure of cranial suture(s) causes abnormal head shape as the brain grows unevenly.  Can be part of various genetic syndromes

craniosynostosis

craniosynostosis where the sagittal suture closes prematurely the skull looks weird —-

posteriorly/anteriorly

two cerebral hemispheres separated by the

median longitudinal fissure

Lobes of the brain have their own divisions separate from the bone sutures, grooves of the brain

sulci

main sulci of the brain, separates frontal and parietal lobes

central sulcus

(5th lobe) is underneath the frontal and parietal lobe

insula

First part of the brainstem

medulla

parts of the brainstem inferior to superior

medulla, pons, midbrain

is where the cranial nerves come off of

brainstem

cranial meninges superficial to deep

dura, arachnoid, pia

dura mater has two different layers associated with it which are (superficial to deep)

periosteal, meningeal

follows all the sulci, Coats the outside of actual brain

pia mater

is filled with CSF and houses the vasculature running through it, No blood vessels in the neuronal tissue, underneath the arachnoid mater

subarachnoid space

is stuck on the inside of the dura mater

arachnoid mater

folds and goes into grooves like pia mater, layer of the dura mater, deeper layer

meningeal layer

(outer layer of the dura mater) - stuck on the bone, pretty difficult to detach from inside of the skull 

periosteal layer

Everywhere there’s a sulci, there is going to be a separation between the periosteal layer and the meningeal layer called ——, (filled with deoxygenated blood)- Help to drain the brain 

dural sinuses

Bacterial Infection of Meninges, rigid neck/ back, nausea/vomiting, photophobia, irritability, bulging fontanelle, abducens nerve palsy, fever, coma

bacterial meningitis

can pinch cranial nerves at the base of the brain - from bacterial infection

meningitis pressure

Wherever dura changes direction

Big dural fold in median longitudinal fissure, Sickle shaped, between the two cerebral hemispheres

falx cerebri

dural fold Sloped like the roof of a tent, Roof over the cerebellum - comes out horizontally 

tentorium cerebelli

dural fold that Separates the right and left side of cerebellum

falx cerebelli

on the outside of the dura, Blood accumulating between brain and bone, Not as serious as subdural, Often related to skull fracture or rupture of an artery

epidural hematoma

decreased consciousness, contusion, dilated, fixed pupil(s), coma, death (~25%), Causes: Arterial laceration- middle meningeal artery from skull fracture, Treatment: osmotic diuretic, surgical evacuation through burr hole/craniotomy

epidural hematoma

hematoma Below dura, No skull fra​​cture - more pressure, More likely to be fatal, Usually related to rupture of the dural sinuses

subdural hematoma

Accumulation of Blood in Subdural Space  - frequently leads to brain damage, altered consciousness, dilated/ nonreactive pupil, coma, death (~60% of cases)

subdural hematoma

cranial fossae include:

anterior, middle, posterior

crista galli, olfactory nerve foramina, orbital plate of frontal bone, cribriform plate, lesser wing of sphenoid

anterior cranial fossa

Attachment  of falx cerebri, in the anterior cranial fossa

crista galli

Attachment of tentorium cerebelli, in the anterior cranial fossa

lesser wing of the sphenoid

nerves in the anterior cranial fossa

CN I tract and bulb, CN I branches, CN II

goes through optic canal in lesser wing of sphenoid

CN II

is the roof of the nasal cavity, CN I sitting on top of the plate

cribriform plate

foramen rotundum, sella turcica, foramen ovale, foramen spinosum,

middle cranial fossa

maxillary branch (V2) of trigeminal nerve exits from —-, part of the middle cranial fossa

foramen rotundum

holds pituitary gland in the middle cranial fossa

sella turcica

mandibular branch (V3)  of trigeminal n. exits from —-, part of the middle cranial fossa

foramen ovale

middle meningeal artery enters through the —-, part of the middle cranial fossa

foramen spinosum

nerves of the middle cranial fossa

CN III - VI

Trigeminal nerve splits into the three roots: ——, Doesn’t divide until underneath the dura

V1-3

Space through which Cranial nerves III, IV, V1, VI travel from middle cranial fossa into orbit

superior orbital fissure

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

posterior cranial fossa

Glossopharyngeal, Vagus, Spinal Accessory nerves, & Internal Jugular vein exit from —-, part of posterior cranial fossa

jugular foramen

Facial, Vestibulocochlear nerves exit from —-, part of the posterior cranial fossa

internal auditory meatus

Hypoglossal n. exits from ——, part of the posterior cranial fossa

hypoglossal canal

Spinal cord, Vertebral arteries, & part of Spinal Accessory n. enter ——, part of the posterior cranial fossa

foramen magnum

posterior cranial fossa nerves

CN VII - XII

CNS starts out as —— and anterior part turns into brain 

neural tube

As brain swells and grows, there is going to be fluid filled space on center of that brain tissue called —— (four) - all filled with CSF

ventricles

connects the 3rd and 4th ventricles

cerebral aqueduct

ventricle Between right and left thalamus there’s a little slit filled with CSF

3rd ventricle

ventricle between cerebellum and pons

4th ventricle

connects the 3rd ventricle to the lateral ventricle

foramen of monro

is highly vascularized, Secretes CSF into the lateral ventricles (runs very closely with them), Then follows the other ventricles and coat the outside of the brain (empties into the subarachnoid space)

choroid plexus

little hands that project into the superior sagittal sinus, how CSF gets back into the vascular system (can also be called granulations)

arachnoid villi

Disturbed formation, flow, or absorption of CSF leading to increase volume in CNS, too much fluid in the ventricles

hydrocephaly

vasculature that goes up to the face and outside of the cranium

external carotid artery

A branch off the External Carotid Artery that supplies the dura, Enters the cranium through the foramen spinosum

middle meningeal artery

vertebral arteries - posterior part of the circle of willis

posterior cerebral, basilar, vertebral, cerebellar arteries

posterior cerebral, vertebral, and cerebellar arteries all branch off of the

basilar artery

most anterior in the vertebral arteries - circle of willis (top arms)

posterior cerebral

posterior to the posterior cerebral vertebral artery

cerebellar arteries

most posterior in the vertebral arteries - circle of willis (feet)

vertebral arteries

internal carotid branches into the

middle cerebral arteries

posterior communicating artery feeds into the

internal carotid artery

two major types of strokes:

ischemic, hemorrhagic

stroke where blood flow is blocked

ischemic stroke

stroke where blood is bleeding out

hemorrhagic stroke

loss of ability to produce/understand language

aphasia

loss of ability to recognize people, objects, sounds, smells, shapes

agnosia

aphasia, agnosia, loss of sensation and movement on contralateral side, damage to motor speech (Broca’s), and language (Wernickes’s) on left side, most common stroke

middle cerebral artery stroke

visual and sensory deficits, less overall chronic disability, midbrain, posterior thalamus—most lethal

posterior cerebral artery stroke

can affect pathways, cranial nerve nuclei, major defects are very damaging or lethal

vertebrobasilar stroke

is the main sinus draining the brain

transverse sinus

supplies the layers of the brain, often ruptures in a epidural hematoma, sandwiched between cranium and brain (makes an imprint on the bone) 

middle meningeal artery

Basilar branches go out to the

cerebellum

Most recoverable stroke is in the

middle cerebral artery

is supplying brain stem so a stroke here will probably be fatal

basilar artery

on the sides of the sella turcica, Damage here damages a lot of cranial nerves 

cavernous sinus

things that pass through the cavernous sinus

internal carotid artery, CN III, IV, V1, V2, VI, sympathetics