This document provides information on the ventricular system of the brain. It describes the lateral ventricles, third ventricle, cerebral aqueduct, and fourth ventricle. It discusses the relations, choroid plexuses, and radiological appearance of each part of the ventricular system. Radiological features on plain X-rays, CT, and MRI are also summarized.

1. C.N.SC.N.S..
Ventricular systemVentricular system

2. Dr.Mohamed Ashraf Zaitoun, MD
Interventional Radiology Consultant, Zagazig University
Hospitals, Egypt
FINR-Switzerland
zaitoun82@gmail.com
www.zaitounclinic.com

3. DedicationDedication
To the memory of my late father, Prof Ashraf ZaitounTo the memory of my late father, Prof Ashraf Zaitoun
Interventional
Radiology Unit,
Zagazig University,
Egypt

4. Ventricular systemVentricular system
**They are fluid filled spaces within the brain related to theThey are fluid filled spaces within the brain related to the
development of the nervous system as a tubulardevelopment of the nervous system as a tubular
structure within the central canalstructure within the central canal..
**They includeThey include::
22lateral ventricleslateral ventricles
33rdrd
ventricleventricle
44thth
ventricleventricle
**33rdrd
, the aqueduct & 4, the aqueduct & 4thth
are midline in position &are midline in position &
continuous with the central canal of the cordcontinuous with the central canal of the cord..

6. MRI Sagittal sectionMRI Sagittal section
Lat vent
Genu
3rd
vent
Sphenoid
sinus
Nasopharynx
Body of CC
Splenium
Quadrigemina
cistern
Pons
4th
vent
Medulla
Cerebellum
Tonsil
Cingulate gyrus
Prepontine cistern

7. Ventricular systemVentricular system
**The ventricular system is also continuous with theThe ventricular system is also continuous with the
subarachnoid space via foramen in the 4subarachnoid space via foramen in the 4thth
ventricleventricle..
**Approximately 25 ml of CSF is fill these spaces inApproximately 25 ml of CSF is fill these spaces in
adultsadults..
**The ventricles are lined by ependyma which isThe ventricles are lined by ependyma which is
invaginated by the choroid plexus >> the bloodinvaginated by the choroid plexus >> the blood
vessels which produce the CSFvessels which produce the CSF..

8. Ventricular systemVentricular system
Lateral ventricleLateral ventricle::
--Each lateral ventricle lies within the corresponding cerebralEach lateral ventricle lies within the corresponding cerebral
hemispherehemisphere..
--They are connected to the 3They are connected to the 3rdrd
ventricle through >> interventricularventricle through >> interventricular
foramen of monro ( at the junction of the ant. Horn of theforamen of monro ( at the junction of the ant. Horn of the
bodybody(.(.
--Each is C-shaped with the limbs of the C facing anteriorly & eachEach is C-shaped with the limbs of the C facing anteriorly & each
one hasone has::
Frontal ( ant. ) hornFrontal ( ant. ) horn
Body ( atrium ) hornBody ( atrium ) horn
Temporal ( inf. ) hornTemporal ( inf. ) horn
Occipital ( post. ) hornOccipital ( post. ) horn

9. Ventricular systemVentricular system
**Frontal ( anterior ) hornFrontal ( anterior ) horn::
--It extends in the frontal lobeIt extends in the frontal lobe..
--It has no choroid plexus withinIt has no choroid plexus within..
--RelationsRelations<<<<
Anterior : genu of corpus callosumAnterior : genu of corpus callosum
Floor : rostrum of corpus callosumFloor : rostrum of corpus callosum
head of caudate ( below & lateralhead of caudate ( below & lateral((
Roof : body of corpus callosum & tapetumRoof : body of corpus callosum & tapetum
Medially : septum pellucidumMedially : septum pellucidum

10. Ventricular systemVentricular system
**Body ( atriumBody ( atrium( :( :
--Lies within the parietal lobeLies within the parietal lobe..
--It has a choroid plexus in the choroidal fissure ( groove betweenIt has a choroid plexus in the choroidal fissure ( groove between
the fornix & the thalamusthe fornix & the thalamus((
--RelationsRelations<<<<
Roof : as frontal hornRoof : as frontal horn
Medially : as frontal hornMedially : as frontal horn
Floor & lateral wall : Thalamus ( mediallyFloor & lateral wall : Thalamus ( medially((
Head of caudate ( latHead of caudate ( lat. (. (
Thalamostriate groove & vein ( inThalamostriate groove & vein ( in
betweenbetween((
Fornix ( above the thalmausFornix ( above the thalmaus((

11. Ventricular systemVentricular system
**Temporal ( inferiorTemporal ( inferior((
--It extends anteriorly into the temporal lobeIt extends anteriorly into the temporal lobe
--It extends down & laterally from the body & then curvesIt extends down & laterally from the body & then curves
somewhat medially towards the temporal polesomewhat medially towards the temporal pole
--It has choroid plexus continuous with that of the bodyIt has choroid plexus continuous with that of the body
--RelationsRelations<<<<
Roof : tail of caudate & amygdaloidRoof : tail of caudate & amygdaloid
Floor : hippocampusFloor : hippocampus
Lateral : tapetumLateral : tapetum

12. Ventricular systemVentricular system
**Occipital ( posteriorOccipital ( posterior((
--It extends posteriorly into the occipital lobeIt extends posteriorly into the occipital lobe
--Trigone is the post. Projection of the body from which it arisesTrigone is the post. Projection of the body from which it arises
--They are usually asymmetrical & if presents on one side only >> it is usually theThey are usually asymmetrical & if presents on one side only >> it is usually the
left , also may be absent or poorly developedleft , also may be absent or poorly developed
--It has no choroid plexusIt has no choroid plexus
--RelationsRelations<<<<
Roof & lateral wall : taperal fibers & opticRoof & lateral wall : taperal fibers & optic
radiationsradiations
Infero-medial : 2 elevationsInfero-medial : 2 elevations<<<<
bulb of post. Horn : produced by fibers of forceps minorbulb of post. Horn : produced by fibers of forceps minor
calcar avis : produced by calcarine sulcus ( ant. Limbcalcar avis : produced by calcarine sulcus ( ant. Limb((
****N.B. >> the ant. & the post. Horns are devoid of choroid plexusN.B. >> the ant. & the post. Horns are devoid of choroid plexus

13. Ventricular systemVentricular system
**Choroid plexus of the lateral ventricleChoroid plexus of the lateral ventricle::
--The choroid plexus of the lateral ventricle >>The choroid plexus of the lateral ventricle >>
production of most of CSFproduction of most of CSF
--Extends from the inferior horn through the bodyExtends from the inferior horn through the body
to the inter-ventricular foramento the inter-ventricular foramen<<<<
Where it is continuous with the 3Where it is continuous with the 3rdrd
ventricleventricle
--They are invaginated into the lateral ventricleThey are invaginated into the lateral ventricle
medially through the choroidal fissuremedially through the choroidal fissure

14. Ventricular systemVentricular system
--Tela choroidaeTela choroidae<<<<
**It is the fold of pia containing the plexusIt is the fold of pia containing the plexus
**It has narrow rounded apex (ant.) at the level of theIt has narrow rounded apex (ant.) at the level of the
inter-ventricular forameninter-ventricular foramen
**Wide (post.) where it is continuous with theWide (post.) where it is continuous with the
subarachnoid spacesubarachnoid space
**If CSF accumulates in this foldIf CSF accumulates in this fold<<<<
Forms a flat trigonal cavum or cistern of the valumForms a flat trigonal cavum or cistern of the valum
interpositum that may be visible on axial CT or MRIinterpositum that may be visible on axial CT or MRI

15. Ventricular systemVentricular system
--Arterial supplyArterial supply<<<<
**Ant. Choroidal arteries ( branches of ICAAnt. Choroidal arteries ( branches of ICA((
**Post. Choroidal arteries ( branch of PCAPost. Choroidal arteries ( branch of PCA((
--Venous drainageVenous drainage<<<<
Choroidal vein which joins the thalamo-striate &Choroidal vein which joins the thalamo-striate &
septal veins to form >> internal cerebral veinseptal veins to form >> internal cerebral vein

16. CT Axial section at 3CT Axial section at 3rdrd
ventricleventricle
Genu of corpus
callosum
Caudate nucleus
Int.capsule
3rd
ventricle
Pineal gland
vermisOccipital lobe
Choroid plexus
Thalamus
Lentiform nucleus
Frontal horn
Pericallosal A

17. CT Axial section at mid ventriclesCT Axial section at mid ventricles
Cingulate gyrus
Body of
lateral
ventricle
Corpus callosum
Falx
cerebri
Occipital horns
Parietal lobe
Corona radiata
Frontal horns
Confluence of
Sinuses (torcula)

18. MRI Coronal section at 3MRI Coronal section at 3rdrd
ventricleventricle
Frontal horns
Fornix
3rd
ventricle
Clivus
Interpeduncular
cistern
Insula
Sylvian fissure
Temporal lobe
Parotid
gland
Odontoid (dens)

19. Ventricular systemVentricular system
Third ventricleThird ventricle >> Slit like>> Slit like
--A narrow cleft in the midline between the 2A narrow cleft in the midline between the 2
thalami which extendsthalami which extends
FromFrom::
Foramen of monro (antForamen of monro (ant.(.(
ToTo::
Aqueduct of sylvius (postAqueduct of sylvius (post.(.(

20. Ventricular systemVentricular system
--RelationsRelations::
**RoofRoof<<<<
Anteriorly : by ant. Commisure , column of fornixAnteriorly : by ant. Commisure , column of fornix
& inter-ventricular foramen of monro& inter-ventricular foramen of monro
Behind this : body of the fornix & choroid plexusBehind this : body of the fornix & choroid plexus
in the choroidal fissurein the choroidal fissure
**floor : hypothalamus with all its structuresfloor : hypothalamus with all its structures
optic chiasmoptic chiasm

21. Ventricular systemVentricular system
**AnteriorAnterior::
Lamina terminalis ( this is the thin ant. Wall of theLamina terminalis ( this is the thin ant. Wall of the
33rdrd
ventricle between the ant. Commisure aboveventricle between the ant. Commisure above
& the optic chaism below& the optic chaism below((

23. Ventricular systemVentricular system
The cerebral aqueductThe cerebral aqueduct::
--Narrow communication between the post. End ofNarrow communication between the post. End of
the 3the 3rdrd
ventricle & superior end of the 4ventricle & superior end of the 4thth
ventricleventricle
--It passes through the brain stem withIt passes through the brain stem with<<<<
Tectum postTectum post..
Tegmentum & cerebral peduncles antTegmentum & cerebral peduncles ant..

24. Ventricular systemVentricular system
--The peri-aqueductal gray matter is the nuclei ofThe peri-aqueductal gray matter is the nuclei of
>> 3>> 3rdrd
, 4, 4thth
& 5& 5thth
cranial nerves which surroundcranial nerves which surround
the aqueductthe aqueduct

26. MRI Sagittal sectionMRI Sagittal section
Lat vent
Genu
3rd
vent
Sphenoid
sinus
Nasopharynx
Body of CC
Splenium
Quadrigemina
cistern
Pons
4th
vent
Medulla
Cerebellum
Tonsil
Cingulate gyrus
Prepontine cistern

27. Ventricular systemVentricular system
Fourth ventricleFourth ventricle
--Lies betweenLies between::
Ant. Surface of the cerebellumAnt. Surface of the cerebellum&&
Post. Surface of the pons & upper medullaPost. Surface of the pons & upper medulla
--Continuous above with the aqueduct & belowContinuous above with the aqueduct & below
with the central canalwith the central canal

28. Ventricular systemVentricular system
--ItIt’’s choroid plexus is invaginated in the lower part of its roof &s choroid plexus is invaginated in the lower part of its roof &
supplied by branch of the inferior cerebellar arterysupplied by branch of the inferior cerebellar artery
--RelationsRelations::
**Floor ( rhomboid fossaFloor ( rhomboid fossa((
Post. Surface of ponsPost. Surface of pons
Upper part of medullaUpper part of medulla
**RoofRoof
Superiorly >> sup. Cerebellar peduncles & sup. Medullary velum inSuperiorly >> sup. Cerebellar peduncles & sup. Medullary velum in
betweenbetween
Inferiorly >> inf. Cerebellar peduncles & inf. Medullary vermis inInferiorly >> inf. Cerebellar peduncles & inf. Medullary vermis in
betweenbetween

29. Ventricular systemVentricular system
--ForaminaForamina::
Three foramina present at the lower part of theThree foramina present at the lower part of the
roofroof<<<<
**Foramen of magendiForamen of magendi
It is a large opening in the inf. Medullary velum &It is a large opening in the inf. Medullary velum &
connects the 4connects the 4thth
ventricle with the cisterna magnaventricle with the cisterna magna
**22foramina of luschkaforamina of luschka
Open into pontine cisternOpen into pontine cistern

31. Ventricular systemVentricular system
Radiological featuresRadiological features
Plain x-raysPlain x-rays
CT & MRI axial cutsCT & MRI axial cuts
MRI sagittalMRI sagittal

32. Ventricular systemVentricular system
Plain x-raysPlain x-rays
--The ventricular system canThe ventricular system can’’t be seen on plaint be seen on plain
radiographyradiography
--But the position of the lateral ventricle isBut the position of the lateral ventricle is
indicated by calcification of the choroid plexusindicated by calcification of the choroid plexus
>> lateral view 2.5 cm above the pineal body>> lateral view 2.5 cm above the pineal body
In OF or FO views it is seen nearly >> alwaysIn OF or FO views it is seen nearly >> always
bilateral & symmetricalbilateral & symmetrical

33. Ventricular systemVentricular system
--The normal position of the 4The normal position of the 4thth
ventricle is seen inventricle is seen in
>> mid-point of Twining>> mid-point of Twining’’s line which runs froms line which runs from
tuberculum sellae to the internal occipitaltuberculum sellae to the internal occipital
protuberanceprotuberance

34. Ventricular systemVentricular system
CT & MRI axial cutsCT & MRI axial cuts
Lower cutsLower cuts
Mid brain levelMid brain level
Higher cutsHigher cuts

35. Ventricular systemVentricular system
**Lower cutsLower cuts::
--44thth
ventricle appears as a CSF filled structureventricle appears as a CSF filled structure
between the brain stem & cerebellumbetween the brain stem & cerebellum

36. CT Axial section above foramenCT Axial section above foramen
magnummagnum
Frontal sinus
Sphenoid sinus
Temporal lobe
Basilar A.
Mastoid cells
Cerebellar
hemisphere
Cisterna magna
Medulla
Optic nerve
Pituitary
Sphenoid bone
Temporal bone
Cerebellar tonsils

37. CT Axial section at 4CT Axial section at 4thth
ventricleventricle
Frontal sinus
Frontal bone
Mid.cerebral A
Basilar A.
Pons
4th
vent
cerebellum
Mid cerebellar
peduncle
Petrous bone
Temporal horn
Ant.cerebral a
Sella turcica
Vermis

38. CECT Axial sectionCECT Axial section aboveabove 44thth
ventricleventricle
Frontal lobe
Ant cerebral A.
4TH
vent
Cerebellum
Pons
Temporal horn
Infundibulum
Post.cerebral A.
Sphenoid bone
Frontal bone
Frontal sinus
Mid.cerebral A

39. Ventricular systemVentricular system
**Mid brain levelMid brain level::
--The aqueduct may be seen with high attenuationThe aqueduct may be seen with high attenuation
peri-aqueductal gray matterperi-aqueductal gray matter

41. Ventricular systemVentricular system
**Higher cutsHigher cuts::
--33rdrd
ventricle between the 2 thalamiventricle between the 2 thalami
--Anterior horns of the lateral ventricles separated by theAnterior horns of the lateral ventricles separated by the
septum pellucidum with the head of caudate indentingseptum pellucidum with the head of caudate indenting
its lateral aspectits lateral aspect
--Post. Horns with the choroid plexus in the trigonePost. Horns with the choroid plexus in the trigone
--Bodies of the lateral ventricles separated by the septumBodies of the lateral ventricles separated by the septum
pellucidum or the corpus callosumpellucidum or the corpus callosum
--Body & head of caudate are seen as high attenuation atBody & head of caudate are seen as high attenuation at
the lateral wall of the lateral ventriclethe lateral wall of the lateral ventricle

42. CT Axial section at 3CT Axial section at 3rdrd
ventricleventricle
Genu of corpus
callosum
Caudate nucleus
Int.capsule
3rd
ventricle
Pineal gland
vermisOccipital lobe
Choroid plexus
Thalamus
Lentiform nucleus
Frontal horn
Pericallosal A

43. CT Axial section at mid ventriclesCT Axial section at mid ventricles
Cingulate gyrus
Body of
lateral
ventricle
Corpus callosum
Falx
cerebri
Occipital horns
Parietal lobe
Corona radiata
Frontal horns
Confluence of
Sinuses (torcula)

44. Ventricular systemVentricular system
**Sagittal MRISagittal MRI::
--33rdrd
ventricle , aqueduct & 4ventricle , aqueduct & 4thth
ventricle can be seenventricle can be seen
in continuity with each other & with the centralin continuity with each other & with the central
canal of the medulla & of the spinal cordcanal of the medulla & of the spinal cord
--The communication of the 4The communication of the 4thth
ventricle with theventricle with the
cisterna magna at the foramen of magendi cancisterna magna at the foramen of magendi can
also be seenalso be seen

45. MRI Sagittal sectionMRI Sagittal section
Lat vent
Genu
3rd
vent
Sphenoid
sinus
Nasopharynx
Body of CC
Splenium
Quadrigemina
cistern
Pons
4th
vent
Medulla
Cerebellum
Tonsil
Cingulate gyrus
Prepontine cistern

46. Ventricular systemVentricular system
CSF prodcution & flowCSF prodcution & flow
ProductionProduction
FlowFlow
AbsorptionAbsorption

47. Ventricular systemVentricular system
**ProductionProduction::
--Total volume of the CSF is 150 ml , 25 ml of itTotal volume of the CSF is 150 ml , 25 ml of it
lies within & around the spinal cordlies within & around the spinal cord
--Produced by the choroid plexus of all ventriclesProduced by the choroid plexus of all ventricles
but mainly from the lateral ventriclebut mainly from the lateral ventricle

48. Ventricular systemVentricular system
**CSF flowCSF flow::
--Lateral ventricle >>foramen of monroLateral ventricle >>foramen of monro<<<<
33rdrd
ventricle >> cerebral aqueductventricle >> cerebral aqueduct<<<<
44thth
ventricleventricle
--Few amount of CSF from the 4Few amount of CSF from the 4thth
ventricle circulates inventricle circulates in
the >>central canal of the spinal cordthe >>central canal of the spinal cord
--Most of the amount pass & leave it through foramen ofMost of the amount pass & leave it through foramen of
magendi >> cisterna magnamagendi >> cisterna magna
Foramina of luschka >> pontine cisternForamina of luschka >> pontine cistern

49. Ventricular systemVentricular system
**CSF absorptionCSF absorption::
--Arachnoid villi & granulations >> SSSArachnoid villi & granulations >> SSS
--Absorption is passive & depends on theAbsorption is passive & depends on the
hydrostatic pressurehydrostatic pressure

51. Ventricular systemVentricular system
Radiological featuresRadiological features
--Skull radiographySkull radiography
--Radionuclide cisternographyRadionuclide cisternography
--Magnetic resonance CSF flow studyMagnetic resonance CSF flow study

52. Ventricular systemVentricular system
--Knowledge of the CSF pathway is important toKnowledge of the CSF pathway is important to
know the site of obstructionknow the site of obstruction<<<<
**lesion obstructing the cerebral aqueduct >>lesion obstructing the cerebral aqueduct >>
dilatation of the lateral & 3dilatation of the lateral & 3rdrd
ventricles , but notventricles , but not
the 4the 4thth
ventricleventricle
**Arachnoiditis blocking the exit foramina of the 4Arachnoiditis blocking the exit foramina of the 4thth
ventricle >> dilatation of all ventriclesventricle >> dilatation of all ventricles

53. Ventricular systemVentricular system
Skull radiographySkull radiography::
--Arachnoid granulations are seen as relativeArachnoid granulations are seen as relative
translucencies or small bony defectstranslucencies or small bony defects
Tangential views show that they are indentation ofTangential views show that they are indentation of
the inner table onlythe inner table only
--Calcification of the arachnoid granulation mayCalcification of the arachnoid granulation may
occur & could be seen on plain filmsoccur & could be seen on plain films
--They are mostly seen along the SSS but also seenThey are mostly seen along the SSS but also seen
around the troculaaround the trocula

54. Ventricular systemVentricular system
Radionuclide cisternographyRadionuclide cisternography::
--The radionuclide is injected into the CSF via lumbarThe radionuclide is injected into the CSF via lumbar
routeroute
--After 1-3 hrs : isotope could be seen in the cisternAfter 1-3 hrs : isotope could be seen in the cistern
--After 3-6 hrs : sylvian & interhemispheric fissureAfter 3-6 hrs : sylvian & interhemispheric fissure
--After 24 hrs : the activity surrounds the brainAfter 24 hrs : the activity surrounds the brain
--In children : circulation is rapid , so it takes less timeIn children : circulation is rapid , so it takes less time
--Normally : seen in ventricles in no timeNormally : seen in ventricles in no time

55. Ventricular systemVentricular system
Magnetic resonance CSF flow studyMagnetic resonance CSF flow study::
--Phase contrast with cardiac gating can be used forPhase contrast with cardiac gating can be used for
>> quantitative & qualitative assessment of CSF>> quantitative & qualitative assessment of CSF
flowflow
--Used to visually demonstrate CSF flow &Used to visually demonstrate CSF flow &
distinguish arachnoid cysts from CSF spacesdistinguish arachnoid cysts from CSF spaces
--Calculate CSF flow velocity & to quantifyCalculate CSF flow velocity & to quantify
volumetric flowvolumetric flow