Cranium: osteology, dural sinuses, ventricular system and meninges Flashcards
The _________ is subdivided into two parts (calvaria and cranial base)
Neurocranium
the dome shape roof of neurocranium
Calvaria
floor of the neurocranium (underneath)
cranial base
The majority of bones in the calvaria are fused via fibrous joints called ________
sutures
separates the parietal and temporal bones
Squamous suture
separates the frontal and parietal bones
coronal suture
Separates the parietal and temporal bones form the occipital bone
Lambdoid suture
Separates the parietal bones
sagittal suture
Where the sphenoid, frontal, temporal, and parietal bones join is called the ________
Pterion
Where the sphenoid, frontal, temporal, and parietal bones join is called the ________
Pterion
What artery is deep to the Pterion_______
middle meningeal artery
What artery is a branch from the external carotid artery?
middle meningeal artery
Injury to the Pterion may produce _______ hematoma
extradural (EPIDURAL)
What bone touched the pillow when you lay down?
Occipital bone
The superior nasal conchae is apart of the ethmoid bone? T or F
true
Covered with muscosa
Increase vascular and mucosal surface area
Warms and moistens air
superior, middle and inferior nasal concha
Which of nasal conchae are apart of the ethmoid bone
Only superior and middle nasal concha
Features of the temporal bones:
external acoustic meatus, styloid process, and mastoid process
What bone is the crista galli, and cribriform plate located?
ethmoid bone
attachment point for the falx cerebri
crista galli
What is the tiny foramina that transmit the olfactory nerves (CN I) of the nasal cavities to the olfactory bulbs of the brain?
Cribriform plate
What artery passes through the foramen spinosum?
middle meningeal artery
What organ is located in the hypophyseal fossa?
pituitary gland
What are the 7 hormones secreted in the anterior pituitary gland?
Prolactin (PRL) Follicle-stimulating hormone (FSH) Luteinizing hormone (LH) Thyroid-stimulating hormone (TSH) Adrenocorticotropic hormone (ACTH) Human growth hormone (HGH) Melanocyte hormone (MSH)
remember “flat gray possum mashed”
What are the 2 hormones secreted by the posterior pituitary gland?
Antidiuretic hormone (ADH) Oxytocin
What artery runs through the carotid canal?
internal carotid artery
What are the 3 divisions of the cranial fossa?
Anterior cranial fossa, middle cranial fossa, and posterior cranial fossa
What lobe is the anterior cranial fossa located in?
frontal lobe
What lobe is the middle cranial fossa located in?
temporal lobe
Where is the posterior cranial fossa located?
cerebellum
Meninges and Spaces of the Spinal Cord:
- contains fat and internal vertebral venous plexus
- “True Space”
epidural space
Meninges and Spaces of the Spinal Cord:
- outermost meningeal layer
- “Tough mother”
dura mater
Meninges and Spaces of the Spinal Cord:
- between dura mater and arachnoid mater
- “potential space”
subdural space
Meninges and Spaces of the Spinal Cord:
- thin, delicate “Spider mother”
- adhered to dura mater
arachnoid space
Meninges and Spaces of the Spinal Cord:
- filled with cerebral fluid
- this is the space you access when doing a lumbar puncture
- “true space”
subarachnoid space
Meninges and Spaces of the Spinal Cord:
- “Tender mother”
- “saran wrap” adhering to cord
pia mater
What are the functions of the meninges?
-protect the nervous system, hold it in place, produce cerebrospinal fluid, and provide a passageway for fluids, nerves, and vessels.
Meninges and Spaces of the Brain:
- potential space
- no epidural fat and venous plexus
epidural space
Meninges and Spaces of the Brain:
- two layers in head
- periosteal layer
- meningeal layer continues with cord dura
- tightly adhered to skull eliminated epidural space
dura mater
Meninges and Spaces of the Brain:
- loosely attached to the dura
- contains arachnoid granulations- small protrusions of arachnoid through dura that absorb CSF flow
arachnoid mater
Meninges and Spaces of the Brain:
- true space
- contains CSF
- contains cerebral arteries and veins
subarachnoid space
Meninges and Spaces of the Brain:
“saran wrap” around the brain
pia mater
Due to trauma
between periosteal layer of dura and bone
arterial bleed require to peel tightly adherent dura
Doesn’t usually cross suture lines
-bi convex shape
Epidural hematoma
What ruptured artery is produces the epidural hematoma?
middle meningeal artery
- often due to trauma
- between the meningeal layer of dura and arachnoid
- may cross suture line
- crescent shape on CT scan
subdural hematoma
What has ruptured during the subdural hematoma?
bridging veins
Superior cerebral veins (_________) that empty into the superior sagittal sinus
Bridging veins
damage/bleeding of the bridging veins causes ________ hematoma
subdural
What hematoma does this describe:
- Deep to arachnoid mater
- Fluid-filled: CSF and blood vessels
subarachnoid hematoma
What has ruptured during a subarachnoid hematoma?
ruptured aneurysm
______ hematoma an accumulation of blood inside the brain, caused by rupture of _____
-most commonly caused by hypertension
Intracerbreal; cerebral artery
- Separates two hemispheres of the cerebrum
- vertical projection
Falx cerebri
- separates two hemispheres of the cerebellum
- vertical projection
Falx cerebelli
- Seperates cerebrum from cerebellum
- horizontal projection
tentorium cerebelli
- covers pituitary gland
- horizontal projection
Diaphragma sellae
What is anterior cranial fossa innervation?
Meningeal branches of V1 (ophthalmic)
What is the middle cranial fossa innervation (medial and lateral)?
medial; meningeal branches of V2 (maxillary)
lateral; meningeal branches of V3 (mandibular)
What is the posterior cranial fossa innervation?
CN X (vagus) C1-C3 (cervical nerves)
The dura mater receives its own vascular supply - primarily from the ________ artery and vein
middle meningeal
- major venous drainage system of the brain, meninges, calvarium, and other structures
- lack of valves
Dural venous sinuses
All dural sinuses ultimately drain into the _________
internal jugular vein
drain flat bones of calvarium
Diploic veins
connect extracranial veins with intracranial dural sinuses
emissary veins
- drain the brain parenchyma
- subarachnoid space
- pierce the meninges and drain into the cranial venous system
cerebral veins
- veins draining cerebrum and cerebellum
- cross subarachnoid and subdural spaces to drain into sinuses
bridging veins
drain CSF from subarachnoid space into dural sinuses
Arachnoid granulations
What is the major venous drainage system of the brain meninges, calvarium, and other structures of the head?
dural venous sinuses
The dural venous are located between what two layers?
periosteal and meningeal layers of dura mater
Do the dural venous have valves?
NO
What sinus is in the superior border of falx cerebri
Receives: superior, cerebral, diploic, and emissary veins and CSF
Superior Sagittal Sinus
What sinus is the inferior margin of falx cerebri?
Receives: a few cerebral veins and veins from the falx cerebri
inferior sagittal sinus
What veins join the inferior sagittal sinus to form the straight sinus?
Receives: superior cerebellar veins, and veins from falx cerebri; drains deep areas of the cerebral hemispheres
Great cerebral vein (vein of Galen)
Junction of falx cerebri and tentorium cerebelli
Receives: inferior sagittal sinus, great cerebral vein, posterior cerebral veins, and veins from falx cerebri
Straight sinus
- falx cerebelli against occipital bone
- Receives: communicates inferiorly w/vertebral plexus of veins
Occipital sinus
- Dilated spaces at the internal occipital protuberance
- Receives: superior sagittal, straight, and occipital sinuses
Confluence of sinuses
- Horizontal extensions from the confluence of sinuses along the posterior and lateral attachments of the tentorium cerebelli
- Receives: confluence of sinuses transverse, superior sagittal, straight superior petrosal inferior cerebral, cerebellar, dipolic and emissary veins
Transverse sinus
- continuation of transverse sinuses to internal jugular vein
- Receives: transverse sinuses, and cerebral, cerebellar, diploic and emissary veins
Sigmoid sinus
- both have a relationship with the petrous part of the temporal bone
- Receives: cavernous sinus and cerebral and cerebellar veins
*receives veins from the internal ear and brainstem
Superior and inferior petrosal sinuses
- Lateral aspect of the body of the sphenoid
- Receives: cerebral and ophthalmic veins, deep veins of the face, sphenoparietal sinuses, and emissary veins
Cavernous sinus
Communicates with the facial vein via the ophthalmic veins
Internal carotid artery passes through it
Cranial nerves going to orbit pass through it
Venous drainage provides pathways for infection
Cavernous Sinus
Infections in face can cause infection in _________ sinus and possibly into eye
cavernous sinus; “Triangle of Death”
What structures pass through the cavernous sinus:
O TOM CAT: Oculomotor nerve (CN III) Trochlear nerve (CN IV) Ophthalmic nerve (V1) Maxillary nerve ( V2) Internal carotid artery Abducent nerve (CN VI)
The CSF is produced in the ________ by the _______
ventricles; choroid plexus
What are the ventricles in the brain?
two lateral ventricles, a third ventricle and a fourth ventricle.
This occurs when blood enters the subarachnoid space after subarachnoid hemorrhage.
Can be caused by:
- overproduction of CSF
- obstruction of CSF flow from the ventricles
- the inability of arachnoid granulations to absorb CSF
- *most commonly at cerebral aqueduct**
Hydrocephalus
What happens when children have hydrocephalus?
size and dimensions of the ventricle increased and as a result the brain enlarges
skull sutures are not fused and head expands
What structure separates the two cerebral hemispheres?
longitudinal fissure
What are the cerebral lobes:
parietal, frontal, occipital and temporal lobes
Where is the Brocas area located?
frontal lobe
Where is the Wernicke area located?
Temporal lobe
Which lobe is being described:
- primary motor cortex
- Intelligence
- Self-control
- Personality
frontal lobe
Which lobe is being described:
- hearing and selective listening
- receives sensory information such as sounds and speech
Temporal lobe
What are acquired language disorders called ______
-fluent or nonfluent speech
aphasia
What area of the brain has the ability to comprehend language, including speech
Wernicke’s area
What area of the brain has the ability to think of the right words, program, and coordinate the sequence of muscle contractions to produce sounds and assemble words into meaningful sentences
broca’s area
What aphasia does this describe:
- broken speech
- frontal lobe
- non-fluent
- aware of deficit
- Writing is also impaired
broca’s aphasia
What aphasia does this describe:
- word salad
- temporal lobe
- impaired comprehension
- Usually unaware of deficit
Wernicke’s aphasia
This aphasia often occurs in the form of infarction from occultations of the internal carotid or middle cerebral artery
The large lesion in the dominant hemisphere affects:
- Broca’s area
- Wernicke’s area
- Arcuate fasciculus
Global aphasia
Which lobe is being described?
- sensory cortex
- reading
- Perception and integration of somatosensory information (e.g. touch, pain pressure, and temperature)
Parietal lobe
Which lobe is being described?
- Mapping the visual world, spacial reason, and visual memory
- Determining color properties of the items in the visual field
- Assessing distance, size, and depth
Occipital lobe
What is the primary sensory cortex?
parietal lobe
What structure coordinates balance and voluntary movement?
Cerebellum
What structure contains ascending and descending tracts
- location for most of the cranial nerve nuclei
- Site of the cardiovascular center
- SIte of the respiratory system
Brain stem
What external feature separates the right and left cerebral hemispheres
Longitudinal fissure
What external feature separates the cerebrum from the cerebellum?
Transverse fissure
What external feature separates the frontal and parietal lobes from the temporal lobe
Lateral fissure
Which of the following sulci separates the occiptal lobes from parietal and temporal lobe
parieto-occipital sulcus