Dural venous sinuses and cerebral venous system Radiology

1. VASCULAR ANATOMY OF BRAIN
DR.D.SUNIL
KUMAR
PART – II VENOUS
SYSTEM

2. • The cerebral venous system, unlike the
majority of the rest of the body, does not
follow the cerebral arterial system.
• Cerebral veins have thin walls with no
muscular tissue and possess no valves.
• They emerge from the brain and lie in the
subarachnoid space, coursing over the surface
of the brain, agregating into larger channels
until they pierce the arachnoid mater and the
meningeal layer of the dura mater and drain
into the dural venous sinuses.

3. • The whole system may be divided
into a number of sections:
–cerebral veins
• superficial
• deep
–dural venous sinuses

4. DURAL VENOUS SINUSES
• Dural venous sinuses are venous channels
located intracranially between the two layers
of dura mater (endosteal layer and meningeal
layer).
• Receive blood from the brain through the
cerebral veins and, CSF from the subarachnoid
space through the arachnoid villi .
• Connected to the diploic veins and the veins of
the scalp through the valveless emissary veins

6. • Lined by endothelium, thick walls, no
muscular tissue and, no valves allowing for
bidirectional blood flow in intracranial veins.
• Blood ultimately drains into the internal
jugular veins

7. The Dural venous sinuses are classified as:
• Unpaired
 superior sagittal sinus
 inferior sagittal sinus
 straight sinus
 occipital sinus
 intercavernous sinus
•Paired
transverse sinus
Sigmoid sinus
inferior petrosal sinus
superior petrosal sinus
cavernous sinus
Sphenoparietal sinus
basilar venous plexus

8. SUPERIOR SAGITTAL SINUS
• It is the largest dural venous sinus.
• It runs in a sagittal plane and occupies the fixed
part of the falx cerebri.
• Begins at the foramen cecum, grooves the vault
of the skull, and terminates at the internal
occipital crest where it usually deviates to the
right to become continuous with the transverse
sinus
• Receives cerebrospinal fluid from the venous
lacunae and blood from the superior cerebral
veins .

9. INFERIOR SAGITTAL SINUS
• The inferior sagittal sinus runs along the
inferior free edge of the falx cerebri.
• It runs from front to back (same as
the superior sagittal sinus) and drains into
the straight sinus.
• It receives tributaries from the falx as well as
some small veins from the medial surface of
the cerebral hemispheres.

12. STRAIGHT SINUS
• It is found at the junction between the falx
cerebri and the tentorium cerebelli and is
triangular in cross section.
• It receives the inferior sagittal sinus, the vein of
Galen at its anterior end and some superior
cerebellar veins along its course, and runs
posteroinferiorly towards the confluence of
sinuses, although the exact drainage is variable:
– confluence of sinuses (56%)
– left transverse sinus (21%)
– right transverse sinus (13%)

15. • It is occasionally duplicated or hypoplastic.
• When absent a persistent falcine sinus is
usually identified, draining directly into the
superior sagittal sinus.

16. . a normal straight sinus.
a h straight sinus, which is smaller than the
internal cerebral veins

17. PERSISTENT FALCINE SINUS
• It is a normal structure in the foetus and is
located within the falx cerebri draining the deep
cerebral venous system to the superior sagittal
sinus.
• Normally it involutes after birth.
• If the straight sinus is absent or thrombosed then
the falcine sinus may recanalise or persist.
• This is frequently seen in association with a vein
of Galen malformation.

18. An Absent Straight Sinus With Duplication Of
The Persistent Falcine Sinus Receiving Inferior
Sagittal Sinus And Vein Of Galen

19. OCCIPITAL SINUS
• It is the smallest of the dural venous sinuses and
lies, on the inner surface of the occipital bone.
• Formed by tributaries from the margins of the foramen
magnum, some of which connect with both
the sigmoid sinus and internal vertebral plexus,
coalesce to pass in the attached margin of the falx
cerebelli to drain postero-superiorly at the confluence
of the sinuses.
• The occipital sinus is worth mentioning when reporting
posterior fossa masses or conditions that will require a
posterior fossa craniotomy, as the sinus may be large
or, more importantly, off midline.

21. INTERCAVERNOUS SINUS
• The intercavernous sinus (anterior and posterior)
are dural venous sinuses which connect the left and
right cavernous sinuses, along with the basilar sinus
(plexus).
• They lie in the anterior and posterior borders of
the diaphragma sellae.
• Additional small venous sinuses in the base of the
pituitary fossa drain into the intercavernous sinuses,
and are a cause of bleeding during transphenoidal
hypophysectomy.
• Dilatation of the intercavernous sinuses on contrast-
enhanced MR images may serve as an ancillary sign for
the diagnosis of carotid-cavernous or carotiddural
fistulas near the sella.

24. TRANSVERSE SINUS
• It drains the superior sagittal
sinus the occipital sinus and the straight sinus,
and empties into the sigmoid sinus which in
turn reaches the jugular bulb.
• The two transverse sinuses arise at the
confluence of the three sinuses at the torcula
herophili or confluence of sinuses.

25. • The transverse sinus is more often asymmetric
than not — usually the right one is bigger, some
say because pulsations of the right atrium are
propagated cranially in a valveless system to
impart a larger capacitance to the ipsilateral
jugular system and intracranial sinuses.
• Highly variable anatomy.
– 20% aplasias of the left sinus
– 39% hypoplasia of the left sinus
– 31% symmetric
– 6% hypoplasia of the right sinus
– 4% aplasias of the right sinus

28. MRV image shows
hypoplastic transverse sinus
without evidence of
thrombosis

29. SIGMOID SINUS
• The sigmoid sinus is the continuation of the transverse
sinus (which is similarly variable in size) as the
tentorium ends. It is here that the transverse sinus
receives the superior petrosal sinus.
• It passes inferiorly in an S shaped groove
posteromedial to the mastoid air-cells to the jugular
foramen, where it ends in the jugular bulb, in the
posterior half of the foramen (pars vascularis).
• It has connections via mastoid and condylar emissary
veins with pericranial veins.

32. INFERIOR PETROSAL SINUS
• It is a plexus of venous channels rather than a
true sinus and drains blood from the cavernous
sinus to the jugular foramen (pars nervosa) or
sometimes via a vein which passes through
thehypoglossal canal to the suboccipital venous
pelxus.
• It runs in a shallow groove between the petrous
temporal bone and basilar occipital bone (on
either side of the clivus). It is connected across
the midline by the basilar plexus.

33. • Along with the cavernous sinus, is receives
tributaries from the medulla
oblongata,pons and inferior surface of
the cerebellum as well as labyrinthine veins
(via the cochlear canaliculus and the
vestibular aqueduct)

36. Inferior Petrosal Sinus MRI — some cross-sectional imaging to help identify sinus
outflow pathways; inferior petrosal sinus extends along the lateral aspect of the dorsum
sella towards the jugular foramen. Cavernous Sinus=blue; inferior petrosal sinus=light
blue; sigmoid sinus=purple

37. SUPERIOR PETROSAL SINUS
• The drains the cavernous sinus,
posterolaterally to the transverse sinus. It
runs along superior aspect of the petrous
temporal bone. It receives:
– cerebellar veins
– inferior cerebral veins
– labyrinthine vein - draining the inner ear
structures

39. SPHENOPARIETAL SINUS
• It is located along the posteroinferior ridge of
the lesser wing of the sphenoid bone. It drains
into the cavernous sinus and receives
tributaries from:
– superficial middle cerebral vein
– middle meningeal vein (frontal ramus)
– anterior temporal diploic vein

43. BASILAR VENOUS PLEXUS
• The basilar venous plexus lies between the
endosteal and visceral layers of the dura on the
inner surface of the clivus.
• It connects the:
– inferior petrosal sinuses
– cavernous sinuses
– intercavernous sinuses
– superior petrosal sinuses
– internal vertebral venous plexus
– marginal sinus (around the margins of foramen
magnum)

46. CAVERNOUS SINUS
• The cavernous sinus is located on either side
of the pituitary fossa and body of the
sphenoid bone between the endosteal and
meningeal layers of the dura.
• It extends from superior orbital fissure
anteriorly to apex of petrous bone posteriorly

47. • Superiorly : optic tract,
optic chiasma, internal
carotid artery
• Inferiorly : greater wing
of sphenoid bone
• Medially : sella turcica
and sphenoidal air
sinus
• Laterally : temporal
lobe with uncus
• Anteriorly : superior
orbital fissure
• Posteriorly : apex of
petrous temporal bone

48. Contents

49. VASCULAR CONNECTIONS
• It receives venous blood
from:
– superior and
inferior ophthalmic veins
– sphenoparietal sinus
– occasionally
• central retinal vein
• frontal tributary of
the middle meningeal vein

50. • Drainage of the cavernous sinus is via:
– superior petrosal sinus to the transverse sinus
– inferior petrosal sinus directly to the jugular bulb
– venous plexus on the internal carotid artery to
the basilar venous plexuses
– emissary viens passing through the:
• sphenoidal foramen
• foramen ovale
• foramen lacerum
• Additionally the cavernous sinuses connect to
each other via the intercavernous sinuses.

52. Cavernous sinus=purple
Inferior petrosal
sinus=orange.
Ovale drainage of the
cavernous sinus=white.
Pterygopalatine fossa
veins=red.
Sphenoparietal sinus-
light blue

55. CEREBRAL VEINS
• They drain the brain parenchyma and are
located in the subarachnoid space. They
pierce the meninges and drain further into the
cranial venous sinuses.
• The cerebral veins lack muscular tissue and
valves. The cerebral venous system can be
divided into:
– superficial (cortical) cerebral veins
– deep (subependymal) cerebral veins

56. SUPERFICIAL VENOUS SYSTEM
• The superficial venous system comprises the
sagittal sinuses and cortical veins.
• The cortical veins course along the cortical sulci,
drain the cortex and some of the adjacent white
matter.
• There are numerous cortical veins and most of
them are unnamed, however the large cortical
veins can be identified and according to their
locations cortical venous system can be
subdivided into superior, middle and inferior
groups.

57. SUPERIOR CEREBRAL VEINS
• Eight to 12 superior cerebral veins drain the
superolateral and medial surfaces of each
hemisphere.
• They ascend to the superomedial border of
the hemisphere, where they receive small
veins from the medial surface, and then open
into the superior sagittal sinus.

58. Superior cerebral veins
(bridging veins) (penetrating
arachnoid and dura mater to
enter superior sagittal sinus)

60. MIDDLE CEREBRAL VEIN
• The superficial middle cerebral vein drains
most of the lateral surface of the hemisphere,
and follows the lateral fissure to end in the
cavernous sinus via sphenoparietal sinus.

62. INFERIOR CEREBRAL VEINS
• Inferior cerebral veins on the orbital surface of
the frontal lobe join the superior cerebral
veins and thus drain to the superior sagittal
sinus.
• Those on the temporal lobe anastomose with
basal veins and middle cerebral veins, and
drain to the cavernous, superior petrosal and
transverse sinuses.

63. SUPERIOR ANASTOMOTIC VEIN OF
TROLARD
• It connects the superior sagittal sinus and
the superficial middle cerebral vein (of
Sylvius).
• Its size is dictated by the relative size of the
superficial middle cerebral vein and the
anastomotic vein of Labbé. The vein of Trolard
is smaller than both of these.

66. INFERIOR ANASTAMOTIC VEIN OF
LABBÉ
• It is the largest channel that crosses the
temporal lobe between the Sylvian fissure and
the transverse sinus and connects
the superficial middle cerebral vein and
the transverse sinus.

69. • The frequency with which the vein of Labbé is
identified varies between 25 and 97% of cases.
• Its location is also highly variable:
– mid-temporal region: 60%
– posterior temporal: 30%
– anterior temporal: 10%
• The anatomy of the vein itself is also variable,
with a dominant single channel, multiple
branching channels and even venous lakes having
been described.

70. DEEP VENOUS SYSTEM
• It consist of lateral sinuses, sigmoid sinuses,
straight sinus and draining deep cerebral veins
(subependymal and medullary veins).

71. Medullary veins
• They are numerous and originate 1-2 cm below
cortical gray matter and pass through deep
medullary white matter and drain into
subependymal veins.
• The medullary veins are arranged in a wedge
shaped manner and distributed at a right angle to
subependymal veins.

74. a microcatheter injection of the distal pericalossal artery (left) and a specimen
(different brain, right). The medullary veins (pink) are collected into the
thalamostriate vein (yellow). The larger sulcal veins (blue) collect the territory of the
cortex (purple)

75. SIGNIFICANCE
• DMV engorgement/thrombosis (even without
major sinus thrombosis) may be part of the
pathologic chain of events that leads to
neonatal encephalopathy associated with WM
lesions , both in preterm and fullterm
patients.

76. Coronal and axial T2-
weighted sections in a full-
term neonate (C/O DIFFICULT
DELIVERY) examined at 9
days (A and B ) and 18
months (C and D ) of life.
Bilateral anterior and
posterior
periventricular radial WM
lesions are due to DMV
pathology in the first
examination (arrows in A and
B). A PVL-like pattern with
hyperintense signal intensity
and reduced thickness of
periventricular WM is evident
on follow-up (C and D ).

77. SUBEPENDYMAL VEINS
• They receive medullary veins and aggregate
into greater tributaries, mainly into
– septal veins
– thalamostriate veins
– internal cerebral veins
– basal vein of Rosenthal
– Vein of Galen.

78. INTERNAL CEREBRAL VEINS
• They are paired, paramedian veins which course
posteriorly along the roof of the third ventricle,
between the two leaves of the velum interpositum.
• Each is formed at the foramen of Monro by the
confluence of the choroidal vein (draining the choroid
plexus of the lateral ventricle), and the thalamostriate
vein (which lies in the groove between the thalamus
and caudate nucleus and receives blood from both).
• The veins of the septum pellucidum usually join the
thalamostriate vein.

82. BASAL VEIN OF ROSENTHAL
• The basal vein, also known as vein of
Rosenthal, originates on the medial surface of
the temporal lobe by the union of anterior
cerebral artery and deep middle cerebral vein.
• It runs posteriorly and medially, passes lateral
to the midbrain through the ambient
cistern to drain into the vein of Galen.
• It is closely related to the posterior cerebral
artery (PCA).

85. VEIN OF GALEN
• The vein of Galen, also known as the great
cerebral vein or great vein of Galen, is a short
trunk formed by the union of the two internal
cerebral veins and basal veins of Rosenthal.
• It curves backward and upward around the
splenium of the corpus callosum and ends at
the confluence of the inferior sagittal
sinus and the anterior extremity of
the straight sinus.