neuro Flashcards
In which cranial cavity does the brainstem lie?
posterior cranial fossa
What connects the 3rd and 4th ventricles?
cerebral aqueduct
What groove separates the pons from the medulla?
pontomedullary junction
Which cranial nerve emerging from the pontomedullary junction has the longest intracranial course?
facial nerve (VII)
What makes up the pyramids of the medulla?
white matter - the corticospinal and corticobulbar tracts
What creates the decussation of the pyramids?
the crossing of the cortiospinal and corticobulbar tracts
What do the olives of the medulla contain?
oliviary nuclei
of the ‘open’ and ‘closed parts of the medulla, which is superior and which is inferior?
open is superior
closed is inferior
What structure does the ‘open’ part of the medulla open out onto?
the pons
Through which foramen does the medulla pass to become the spinal cord?
the foramen magnum
what ventricle is the cranial part of the medulla open with?
4th ventricle
What does the caudal part of the medulla surround?
the central canal
What is the middle cerebellar peduncle made up of?
centripetal fibres
What is immediately superior to the midbrain?
the thalamus
What is immediately inferior to the midbrain?
the pons
What makes up the cerebral peduncles (crus cerebri)?
white matter - ascending and descending tracts
What ventricle lies in the thalamus?
3rd ventricle
What two structures make up the diencephalon?
the thalamus and hypothalamus
Which two parts of the brain does the diencephalon lie between?
midbrain and cerebrum
What is the name of the structure connecting the two cerebellar hemishpheres?
vermis
To what parts of the brain is the cerebellum connected to by peduncles?
connected to…
midbrain by the superior peduncle
pons by the middle peduncle
medulla by the inferior peduncle
What is the ventricular space that lies immediately anterior to the cerebellum?
the 4th ventricle
What cranial cavity is the cerebellum in contact with?
posterior-parietal
What foramen does the cerebellum sit directly above?
foramen magnum
What is cerebellar coning?
when there is a sudden drop in intracranial pressure, and the cerebellar tonsils herniate through the foramen magnum
What is the large fissure separating the 2 cerebral hemispheres?
the median longitudinal fissure
What connects the 2 cerebral hemispheres?
the corpus callosum
What nerve fibres are carried in the corpus callosum?
commissural fibres
what cranial cavities does the cerebral hemispheres sit on top of?
the anterior and middle cranial fossa
which lobe contains the primary motor cortex?
frontal
which lobe contains the primary sensory cortex?
parietal
which lobe contains the primary visual cortex?
occipital
which lobe contains the primary auditory cortex?
temporal
name the three layers of the vertebral canal from inside to outside..
pia
arachnoid
dura
at what level does the spinal cord terminate in an adult?
L1/2
at what level does the spinal cord terminate in an infant?
L3
at what level does the dura mater terminate?
L2
at what level does the arachnoid mater terminate?
L2
between which two landmarks does the dura mater extend?
from the foramen magnum to the filum terminale
what happens to the pia mater inferior to the spinal cord?
it fuses with the filum terminale
What is the filum terminale?
a continuation of the conus medullaris, it is made up of pia mater and extends to the coccyx
What is the conus medullaris?
the tapered, lower end of the spinal cord
What is the cauda equina, and where does it begin?
a bundle of spinal nerves arising from lumbar enlargement
it begins at L4 and surrounds filum terminale
What occupies the space between the end of the spinal cord and the termination of the dura and arachnoid? What does it contain?
dural sac, it contains cerebrospinal fluid
At what level would you perform a lumbar puncture in an adult?
between L3/4
How would you position the patient to perform a lumbar puncture, why?
curled forward in foetal position - this increases intervertebral space
What are upper and motor neurons and where are they located?
a neuron with a cell body inside the spinal cord and axon projecting out to effector organ
Is damage to the cauda equina considered an upper or lower motor neuron lesion?
lower
Name the 7 layers of the spinal cord from inside to outside…!!
central canal –> ependymal cells –> grey matter –> white matter –> pia mater –> arachnoid mater –> dura mater
what is the central canal a continuation of? What does it contain?
the 4th ventricle, contains CSF
what is the function of the ependymal cells?
helps CSF circulate, takes part in CSF production
from which arteries do the L & R vertebral arteries arise?
subclavian
from which arteries do L & R internal carotid arteries arise?
common carotids
which arteries connect the internal carotids with the posterior cerebrals?
posterior communicating
which artery connects the anterior cerebrals?
anterior communicating
in which fissure does the anterior cerebral artery travel?
median longitudinal fissure
in which sulcus does the middle cerebral artery travel?
lateral sulcus
which cerebral artery is most commonly affected by a stroke?
middle cerebral artery
which parts of the brain does the vertebro-basilar system supply?
brainstem, occipital lobes and cerebellum
which cerebral artery runs immediately superior to the vertebro-basilar system?
posterior cerebral artery
which cranial nerve emerges just above the superior cerebellar artery? what are the clinical manifestations of palsy of this nerve?
oculomotor nerve (III) - palsy would result in drooping of eye (ptosis)
What is the dilatation on the terminal part of the common carotid artery called? what is its function?
the carotid sinus - it is a pressure receptor which monitors blood flow to the head
Where is the carotid body located? what is its function?
it is an area on the posterior wall of the terminal common carotid artery, it contains chemoreceptors that are sensitive to low oxygen levels (anoxia).
what do the veins of the brain drain into?
dural venous sinuses
into which vein do the dural venous sinuses drain?
internal jugular vein
What 4 veins drain into the cavernous sinus?
superior and inferior opthalmic, superficial middle cerebral and sphenoparietal
What structure in the skull base is the cavernous sinus closely related to?
the body of the sphenoid
cavernous sinus thrombosis might result in what clinical features? why?
loss of vision and bulging eyes, due to compression of optic chiasm
branches of which artery fuse to form the anterior spinal artery?
vertebral artery
which arteries are the posterior spinal arteries branches of? (directly and indirectly)
posterior inferior cerebellar arteries (indirectly) vertebral artery (directly)
what fluid circulates in the subarachnoid space?
CSF
what other structures are present in the subarachnoid space?
blood vessels, spongy bone/trabeculae, arachnoid villi
what structures does the falx cerebri separate?
cerebral hemispheres
which dural sinus runs within the upper border of the falx cerebri?
superior saggital
which structures does the tentorium cerebelli separate
occipital lobes from the cerebellum
what is the middle meningeal artery a branch of?
maxillary artery
what foramen does the middle meningeal artery enter the cranial cavity through?
foramen spinosum
What embryological structure does the ventricles form from?
neural tube
where does the anterior horn of the lateral ventricle lie?
frontal lobe
where does the body of the lateral ventricle lie?
partietal lobe
where does the posterior horn of the lateral ventricle lie?
occipital lobe
where does the inferior horn of the lateral ventricle lie?
temporal lobe
where does the interventricular foramen (foramen f monro) lie?
temporal lobe
where does the 3rd ventricle lie?
temporal lobe - in the thalamus
What are the specialised structures that generate CSF?
choroid plexus
how does CSF pass into the subarachnoid space from the 4th ventricle?
either through the foramina of Luschka or through the foramen of Magendie
at which location is CSF reabsorbed back into general circulation?
superior saggital sinus
What kind of fibres pass through the corpus callosum?
commissural fibres
what are the 4 parts of the corpus callosum?
rostrum, genu, body, splenium
what is the bulbous projection on the floor of he lateral ventricle?
the caudate nucleus
What is most sensory information related to?
the ventro-postero-lateral (VPL) nucleus of the thalamus
what is the dural fold overlying the pituitary gland?
diaphragma sellae
what are the colliculi in relation to the pineal gland
inferiormedially
what structures constitute the basal ganglia?
globus pallidus and thalamus
what are the fibres that connect the cerebral hemispheres with other parts of the brain?
geniculate fibres
which group of structures is the substantia nigra functionally a part of?
basal ganglia
where is the red nucleus in relation to the substantia nigra?
anterior
which part of the pons do motor fibres and sensory fibres that form the medial lemniscus supply occupy?
mid-pons
what fibres make up the olive?
inferior olivary nuclei
what feature can allow a cervical spinal cord section to be identified?
cervical swelling, well developed ventral horn
what feature can allow a thoracic spinal cord section to be identified?
small ventral horn
what feature can allow a lumbar spinal cord section to be identified?
lumbar swelling, well developed ventral horn- more rounded than cervical segment
what feature can allow a sacral spinal cord section to be identified?
small amount of white matter, predominantly grey matter. Spinal cord significantly narrower
from which aspect of the spinal cord do motor fibres project?
anterior
why does the size of ventral grey horn vary along the spinal cord?
cervical enlargement - brachial plexus
lumbar enlargement - lumbosacral plexus
