1. Venous sinuses
Dr.Saeed Mustafa

2. Cranial Meninges

3. Meninges of the Spinal Cord
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Spinal cord
Ventral root
Subarachnoid
Pia mater space
Dorsal root
Spinal nerve Arachnoid mater
Epidural space
Dorsal root Dura mater
ganglion
Dorsal root
Dorsal branch
Spinal
(dorsal ramus)
nerve
Ventral branch
Dorsal root (ventral ramus)
ganglion
Spinal cord
Ventral root
Epidural
space
Thoracic
vertebra Body of
vertebra
(a) (b)
3

5. CRANIAL MENINGES
• Dura:
– an inner (meningeal) layer and outer (periosteal) layer
– Most of the dura’s venous sinuses lie between the dural layers
– Dural layers are generally fused, except where they separate to
provide space for the venous sinuses and where the inner
layer forms septa between the brain portions
– Outer layer firmly attached to inner surface of cranial bones;
inner layer continuous with spinal dura

6. Meninges: Dura Mater
• Reflections:
Falx cerebri:
Midline fold of dura mater
extending between two cerebral
hemispheres.
Tentorium cerebelli:
Dural fold located between
cerebellum and occipital lobes of
cerebral hemispheres.

7. Meninges: Dura Mater
• Reflections:
Falx cerebelli:
Dural fold between two cerebellar
hemispheres.
Diaphragma sellae
Dural fold over hypophyseal
fossa.

8. CRANIAL MENINGES
CRANIAL MENINGES
• Arachnoid:
– Delicate avascular membrane covers the subarachnoid
space
– Between the arachnoid and dura mater lies the subdural
space
– Arachnoid granulations project into the superior sagittal
sinus

9. • Arachnoid granulations－ project into sinuses of dura mater, serve as
sites where cerebrospinal fluid diffuses into bloodstream

10. Circulation of cerebrospinal fluid
CSF drains from lateral ventricle interventricular foramina third ventricle
mesencephalic aqueduct median and two lateral apertures
fourth ventricle
subarachnoid space arachnoid granulations superior sagittal sinus vein

11. CRANIAL MENINGES
• Pia:
– Thin connective tissue membrane that covers the brain
surface and extends into sulci and fissures and around
blood vessels throughout the brain
– Beyond the end of the spinal cord continues as the
filum terminale

12. Dural Nerve Supply
• Branches of trigeminal,vagus
and 1st 3 cervical nerves
• Sensitive to streching which produces the sensation
of headache

13. Dural arterial supply
Int. carotid artery
Maxillary
Ascending pharyngeal
Occipital
Vertebral
*Middle meningeal artery

14. Intra cranial hemorrhage
1.Extra dural (middle meningeal artery)
2.Subdural (sup.cerebral vein)
3.Subarachnoid (the circle of willis)
Blood stained csf
4.Cerebral (lenticulostriate artery)

15. VENOUS DRAINAGE
• Venous drainage of the brain and
coverings includes veins of the brain
itself, dural venous sinuses, dura’s
meningeal veins, and diploic veins
• Eventual cerebral venous drainage is
the internal jugular vein
• Cerebral veins contain no valves

16. Vasculature: Venous Sinuses

17. Dural venous sinuses
• :
Superior sagittal sinus:
Lies along superior margin of falx
cerebri.
receives in its course the sup.cerebral vein
Inferior sagittal sinus:
Lies along inferior margin of falx
cerebri.
joins great cerebral vein

18. 18

19. Meninges: Dura Mater
• Dural venous sinuses:
Straight sinus:
Lies at intersection of falx cerebri and
tentorium cerebelli.
Confluence of sinuses:
Common confluence of superior
sagittal sinus and straight sinus.

20. Venous sinuses

21. Meninges: Dura Mater
• Dural venous sinuses:
Transverse:
Begins at confluence of sinuses.
Extends along edges of tentorium
cerebelli.
Right receives blood from superior
sagittal sinus.
Left receives blood from straight sinus.
receives sup.petrosal sinus,inf.cerebral n cerebellar veins n
diploic veins

23. Meninges: Dura Mater
• Dural venous sinuses:
Sigmoid:
Continuation of straight sinus.
“S”-shaped.
Ends at jugular foramen:
Joins internal jugular vein.

24. • Superior n inferior petrosal sinuses
• Petrous part of temporal bone
• Sup.petrosal sinus drains the cavernous sinus
into transverse sinus
• Inf.petrosal sinus drains the cavernous sinus
into IJV

25. Vasculature: Venus Sinuses

26. 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

27. Cavernous sinus
• Middle cranial fossa
• Extends from Sup.orbital fissure to petrous part
of temporal bone
• Tributaries
• Sup.n inf.ophthalmic veins,cerebral veins,the
sphenoparietal sinus n the central vein of retina
• Drains Posteriorly into sup n inf petrosal sinuses
and inferiorly into pterygoid venous plexus

28. Cavernous sinus
• Position: lies on each side of sella turcica
• Relations of cavernous sinus:
– Internal carotid artery and abducent nerve run through the sinus
– Oculomotor and trochlear nerves and ophthalmic and maxillary
divisions of trigeminal nerve lie in the lateral wall of the sinus

29. Veins of brain
Superficial cerebral veins
• Drain blood from cortex
and subcortical medullary
substance and empty into
adjacent sinuses of dura
mater

30. Veins of brain
• Deep cerebral veins:
drain deeper parts of
hemispheres, basal
nuclei, internal
capsule, diencephalon
and choroid
plexus, ultimately form
great cerebral vein which
enter straight sinus

33. Thanku