Transcript Ventricles & CSF cisterns

Ventricles & CSF cisterns
Ventricles
• CSF filled spaces in the brain related to
development of the nervous system as a
tubular structure with central canal
• Lined with ependyma
• Plexuses of highly vascular pia mater form
choroid plexuses which produce CSF
Lateral Ventricles
• C-shaped facing anteriorly
• Occupy each cerebral hemisphere
• Communicates with 3rd ventricle at
junction of anterior horn and body –
interventricular foramen (of Monro)
Lateral Ventricles
• Anterior horn – within frontal lobe
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Anterior: genu corpus callosum
Roof: body corpus callosum
Medial: septum pellucidum
Floor/lateral wall: head of caudate nucleus
• Body – within parietal lobe
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Roof: body corpus callosum
Medial: septum pellucidum
Lateral wall: body of caudate nucleus
Floor: thalamus (medially)
Lateral Ventricles
• Temporal (inferior) horn
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Roof: tail of caudate nucleus
Floor: hippocampus
Lateral: tapetum (fibres of corpus callosum)
Anterior: amygdaloid nucleus
• Occipital horn (posterior)
– Extends from posterior convexity of the “C” – trigone
– Lateral: tapetum & optic radiation
– Medial: white matter indented by grey matter of
calcarine sulcus (calcar avis)
Choroid plexus
• Composed of invaginated highly vascular pia called tela
choroidea
• Extends from inferior horn, body into intraventricular
foramen and continuous in 3rd ventricle. 4th ventricle also
contains a chorioid plexus.
• Blood supply
– Anterior choroidal (br internal carotid) enters anterior part of
temporal horn
– Posterior choroidal (br PCA) enters body of lateral ventricle
above the thalamus
• Venous drainage
– Choroidal v in inferior horn, passing anteriorly to intraventricular
foramen, joins with thalamostriate v to form internal cerebral v
Third ventricle
• Slit like space between the thalami
• Thin anterior wall (lamina terminalis) from
anterior commissure superiorly to optic chiasm
inferiorly
• Inferiorly extension into optic chiasm
(supraoptic recess) and infundibulum
(infundibular recess)
• Posterior extension into pineal stalk (pineal
recess) and suprapineal recess above this
Third ventricle
• Anterior: anterior commissure
• Roof: anterior commissure, intraventricular
foramen, body of the fornix
• Floor: structures of hypothalamus incl. pituitary
• Lateral: thalami
• Thalami are connected across the ventricle in
60% of people by a non-neural connection –
massa intermedia
Cerebral Aqueduct
• Narrow channel passing through
brainstem connects posterior end of 3rd
ventricle and superior end of 4th ventricle
• 1.5cm length, 1-2mm diameter
• Anterior: cerebral peduncles & tegmentum
• Posterior: tectum
• Nuclei of CN III, IV, V surround aqueduct
Fourth ventricle
• Extends as a widening of the aqeduct posterior to the
pons to the obex (caudal tip of the fourth ventricle; a
marker for the level of the foramen magnum of the skull)
• Floor: rhomboid fossa (pons and upper part of medulla)
• Roof: cerebellum (superior and inferior medullary vela)
• Lateral: cerebellar peduncles
• Communicates with the subarachnoid space through
– Median aperture (foramen of Magendie) in the inferior medullary
vellum open into the cerebellomedullary cistern (cisterna magna)
– two lateral foramina of Luschka in the lateral recesses open
anteriorly into the pontine cistern
Cisterns
• Collections of deep CSF spaces around the brain
• Cerebellomedullary cystern
– posterior to medulla and inferior to cerebellar hemispheres
– Receives CSF from 4th ventricle via median aperture
– Continues as spinal subarachnoid space through foramen
magnum
– Contents: vertebral a and posterior inferior cerebellar branch
• Pontine cistern
– Between pons and clivus
– Cerebellomedullary cystern above, Interpenduncular cistern
below
– Contents: basilar artery and assoc branches
• Interpenduncular cistern