Transcript The Meninges and Blood Vessels of Brain and Spinal Cord, and the

The Meninges and Blood Vessels
of Brain and Spinal Cord,
and the Cerebrospinal Fluid
SHANDONG UNIVERSITY
Liu Zhiyu
Meninges of Brain and Spinal Cord
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The spinal cord and brain are surrounded by
three membranes, the meninges.
Named from the outside inward they are
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Dura mater
Arachnoid mater
Pia mater
The Meninges of Spinal Cord
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Spinal dura mater
Spinal arachnoid mater
Spinal pia mater
Spinal Dura Mater
Characters
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A dense, fibrous membrane
that encloses the spinal cord
and cauda equina
Above, attached to
circumference of foramen
magnum
Below, becomes thinner at
level of S2, invests filum
terminale to attach at back of
coccyx
On each side, continuous with
external membrane of spinal
nerves at intervertebral
foramina
Spinal Dura Mater
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Epidural space
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Position: lies between spinal dura
mater and periosteum of vertebral
canal
Contents: a quantity of loose
connective tissue, fat, lymphatic
vessels and vertebral venous
plexus, the spinal nerves on each
side pass through the epidural
space which is applicable for block
anesthesia
Subdural space
Spinal Arachnoid Mater
Characters
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A thin, delicate, tubular
membran loosely
investing spinal cord
Above, it is continuous
with cerebral arachnoid
mater
Subarachnoid Space
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Position: lies between pia
and arachnoid maters
containing cerebrospinal
fluid
Terminal cistern: the
largest part of subarachnoid
space extending from
termination of spinal cord to
level of S2, where it is
occupied by nerves of
cauda equina, so it is the
best site for a lumbar
puncture
Lumbar spinal puncture (spinal tap)
Spinal Pia Mater
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A delicate vascular membrane
that closely invests the spinal
cord
Denticulate ligament: consist
of 21 pairs triangular
ligaments extending from
spinal cord on each side
between anterior and posterior
roots of spinal nerves to
spinal dura mate; these
ligaments help to fix position
of spinal cord.
Filum terminale: an
extension of pia beyond conus
medullaris
The Meninges of Brain
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Cerebral dural mater
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Cerebral arachnoid mater
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Cerebral pia mater
Cerebral Dural Mater
Characters
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A thick and dense
inelastic membrane that
composed of two layers,
an inner or meningeal
and outer or endosteal
It is in loose contact with
calvaria, and most
strongly adherent to
base of skull
Cerebral dural mater
Four septa
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Cerebral falx
Tentorium of cerebellum
－
in front there is a gap, the
tentorial incisure, for
passage of midbrain
Cerebellar falx
Diaphragma sellae
Cerebral Dural Mater
Sinuses of duramater
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Superior sagittal sinus
Inferior sagittal sinus
Straight sinus
Confluence of sinus
Cerebral Dural Mater
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Transverse sinus
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Sigmoid sinus
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Superior petrosal sinuses
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inferior petrosal sinuses
Cerebral Dural Mater
Cavernous sinus
 Position: lies on each side of
sella turcica
 Traversing the cavernous sinus
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Internal carotid artery
Abducent nerve
Traversing the lateral wall of the
cavernous sinus
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Oculomotor nerve
Trochlear nerve
Ophthalmic nerve
Maxillary nerve
Cerebral Dural Mater
The flowing of the blood in dural sinus
Sup. sagittal sinus
Inf. sagittal sinus
Straight sinus
Confluence of sinus
Transverse sinus
Sup. petrosal sinus
Sigmoid sinus
Cavernous sinus
Inf. petrosal sinus
Internal jugular vein
Cerebral Arachnoid Mater
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Characters: a delicate
membrane covering
brain loosely, passing
over sulci and entering
only cerebral
longitudinal and
transverse fissures
Cerebral Arachnoid Mater
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Arachnoid granulations
－ project into sinuses of dura
mater, serve as sites where
cerebrospinal fluid diffuses into
bloodstream
Subarachnoid Cisterns
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Cerebellomedullary cistern
Chiasmatic cistern
Interpeduncular cistern
Pontine cistern
Superior cistern
Cerebellomedullary cistern
Intracranial hemorrhages…
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Extradural or epidural hemorrhage: blood collects
between the calvaria and the periosteal layer of dura
Intracranial hemorrhages…
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Subdural hematoma: blood collects between the
dura and arachnoid
Intracranial hemorrhages
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Subarachnoid hemorrhage: blood flows into the
subarachnoid space and mixes with cerebrospinal
fluid
Cerebral Pia Mater
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Closely invests brain
surface
In some areas the pia
invaginates into ventricles
to take part in the
formation of choroids
plexus
Circulation of Cerebrospinal Fluid (CSF)
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Cerebrospinal fluid is a
clear colorless fluid
Nourishes brain
Removes waste
Conducts chemical signals
between parts of CNS
Liquid cushion for brain and
spinal cord
Production: produced by the
choroids plexuses within the
lateral, third and fourth
ventricles
Choroid plexus = choroidal epithelium
surrounding brain capillaries
CSF volume = 150 ml
75 ml in cisterns
50 ml in subarachnoid space
25 ml in ventricles
CSF formation = 450-600 ml/day
Circulation of Cerebrospinal Fluid (CSF)
CSF drains from lateral ventricle
mesencephalic aqueduct
interventricular foramina
fourth ventricle
third ventricle
median and two lateral apertures
subarachnoid space arachnoid granulations superior sagittal sinus
vein
Hydrocephalus
Hydrocephalus
Arteries of Brain
Two sources
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Internal carotid artery:
supplies anterior 2/3 of
cerebral hemisphere and parts
of diencephalon
Vertebral artery: supplies
postterior 1/3 of cerebral
hemisphere and parts of
diencephalon, brain stem and
cerebellum
Internal Carotid Artery
Branches
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Anterior cerebral artery
Middle cerebral artery
Anterior choroidal artery
Posterior communicating artery
Internal Carotid Artery
Anterior cerebral artery
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Joined the fellow of the opposite
side by the anterior
communicating artery
Cortical branches: supply all
medial surface of the cerebral
cortex as far back as the
parietooccipital sulcus and
superior border of the
suprolateral surface of the
cerebral hemisphere
Central branches: supply
caudate nucleus, anterior part of
lentiform nucleus and anterior
limb of internal capsule
Internal Carotid Artery
Middle cerebral artery
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Cortical branches: supply
most of superolateral surface
of cerebral hemisphere and
insular lobe
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Central branches: supply
lentiform and caudate nuclei,
genu and posterior limb of
internal capsule
(lenticulostriate artery)
Internal Carotid Artery
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Anterior choroidial artery：
passes backward, enters inferior
horn of lateral ventricle, and
ends in choroid plexus. It
supplies lateral geniculate body,
posterior limb of internal capsule,
middle 3/5 of crus cerebri and
globus pallidus
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Posterior communicating
artery: runs backward to join
posterior cerebral artery
Vertebral Artery
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Cranial branches
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Anterior and posterior spinal
arteries
Posterior inferior cerebellar
artery
Branches of basilar artery
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Anterior inferior cerebral
artery
Labyrinthine artery
Pontine arteries
Superior cerebellar artery
Posterior cerebral artery
Vertebral Artery
Posterior cerebral
artery
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Cortical branches: supply
medial and inferior surfaces
of temporal lobe and
occipital lobe
Central branches: supply
dorsal thalamus, medial
geniculate body,
hypothalamus and
subthalamus
Cerebral Arterial Circle ( Circle of Willis )
Formation
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Anterior communicating artery
Both anterior cerebral arteries
Internal carotid arteries
Posterior communicating arteries
Posterior cerebral arteries
Position: lies on sella turcica around
optic chiasma, tuber cinereum and
mamillary bodies
Microaneurysm
Lenticulostriate arteries
Subarachnoid hemorrhage
Veins of Brain
Superficial cerebral veins
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Drain blood from cortex and subcortical
medullary substance and empty into
adjacent sinuses of dura mater
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Superior cerebral v. ascend over
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the lateral surface of the cerebral
hemisphere and drain into the superior
sagital sinus.
Inferior cerebral v. drain into the.
transverse sinus and cavernous sinus
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Superficial middle cerebral v.
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drains the lateral surface of the
cerebral hemisphere . it empties into
the cavenous sinus.
Deep middle cerebral v. drains
insula and is joined by the anterior
cerebral and striate veins to form the
basal vein.
Veins of Brain
Deep cerebral veins
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Drain deeper parts of
hemispheres, basal nuclei,
internal capsule diencephalon and
choroid plexus
Ultimately form great cerebral
vein which enter straight sinus
Arteries of Spinal Cord
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Two sources
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Anterior and posterior spinal arteries
Branches of segmental arteries:
radicular arteries of posterior intercostals
arteries, lumbar arteries, and lateral
sacral arteries
Damage area: T1~T4,ventral part of L1
vascular ring ( vasocorona )
Arteries of Spinal Cord
Posterior spinal a.
Vascular ring
Anterior spinal a.
Radicular a.