SPACES FORMED BY MENINGES AND MENINGEAL COVERINGS OF SPINAL CORD

Presented by

Jega Subramaniam

Guided by Dr Mannah Chandra and Dr Venugopal

SPACES FORMED BY MENINGES AND

MENINGEAL COVERINGS OF SPINAL CORD

Extradural, Subdural,

Subarachnoid Spaces in Brain

Subarachnoid Cisterns

Meningeal Coverings of Spinal Cord

Clinical Anatomy

Outline

= Extradural Space

Potential Space between the inner aspect of skull bone and the endosteal layer of dura mater

Normally absent or very minute space

Epidural Space

Epidural Hematoma• Blood escapes from the

ruptured blood vessel --Meningeal Artery

• Lucid Interval

Subdural Space

Potential Space between the dura mater and arachnoid mater

Traversed by cerebral veins before draining into dural venous sinuses

Subdural Space

Head injury that tears a blood vessel

Blood escapes from the ruptured blood vessel --- Cerebral Veins

Subdural Hematoma

Space between the arachnoid and pia mater

Surrounds brain and spinal cord – Ends at Lower Border of S2 vertebra

Contains - Cerebrospinal Fluid , large vessels of brain

Collagen and elastic fibrous tissue arranged in network manner

Cranial nerves passes through the space

At base of the brain and around the brain the stem , It opens/enlarges into Cisterns

Subarachnoid Space

Blood clot in the subarachnoid space

Can be due to Bleeding from a cerebral aneurysm

Head injury

SUBARACHNOID HEMATOMA

Latin = “ Box ”

Intercommunicating pools at the base and around the brain stem

Enlarged Subarachnoid Space

Function – Having more amount of CSF it can give extra protection to underlying tissue . Forms cushions around the medulla oblongata.

Subarachnoid Cisterns

Cerebellomedullary Cistern /

Cisterna Magna *

Cisterna Pontis *

Interpeduncular Cistern

Lumbar Cistern *

Cistern of Great

Cerebral Vein

Cistern of Lateral Sulcus

Cerebellomedullary Cistern / Cisterna Magna

Largest

Connects the inferior surface of cerebellum and medulla oblongata

Receives the CSF from the fourth ventricle through Median Foramen of Magendie

Cisterna Pontis On the ventral aspect pons

Contains Basilar artery and its branches

Interpeduncular Cistern

• Between two temporal lobes

• Contains important Circle of Willis

Cistern of Great Cerebral Vein• Between the splenium

of corpus collosum and superior surface of cerebellum

• Contains pineal gland and great cerebral vein

Lumbar Cistern At Lumbar Region. Distal to

termination of spinal cord(LB of L1)

Lumbar Puncture – Space between L3 and L4

Communicates through apertures in the 4th ventricles

- Median Foramen of Megendie -

Drains the CSF to Subarachnoid Space mainly to Cisterna Magna

- 2 Lateral Foramina of Luschka Opening in each lateral extremity of the lateral recess of the fourth ventricle

How CSF flows from Ventricular System to Subarachnoid Space

Fourth Ventricle

Lateral Foramen

Median Foramen

Third Ventricle

Lateral Ventricle

Foramen of Monro

Cerebral Aqueduct

Spinal Cord is surrounded by 3 meninges . Dura , Arachnoid and Pia mater

Dura Mater

Arachnoid Mater

Pia Mater

Subdural Space

Subarachnoid Space --- contains CSF

Vertebral Canal

Epidural Space --- Epidural anaesthesia is given

Dura Mater , Arachnoid Mater , Subarachnoid

Space extends up to S2 vertebra.

Meningeal Covering Of Spinal Cord

Spinal Cord ends at lower border of L1 as conus medularis . So Below L2 – Lumbar Puncture is done without any damage to the spinal cord

Below Conus Medularis - Only pia mater is continued as thin fibrous cord = filum terminale ---attach to periosteum of dorsal surface of Co 1 segment

Conus Medular

is

Filum Terminal

e

l.B of L 1

Co 1

Lateral projection of pia mater to the dura mater = denticulate ligament – 21 pairs –teeth like projection – keeps the spinal cord in position

Linea splendens – thickening at anteromedian sulcus

denticulate

ligament

Cauda Equina ---- Resembles horse tail

Dorsal and Ventral nerve roots of right and left sides of L2 to S5 nerves lies almost vertically around the filum terminale

Cauda Equina = This nerves roots + conus medularis + filum terminale

( bundle )

Clinical Anatomy

Conus Medularis Syndrom

e

Cadua Equina

Syndrome

Epidural Hematoma

Subdural Hematoma

Subarachnoid

Hematoma

Injury to S2,S3,S4 spinal segment --- Anaesthesia in Perineum . Sexual Fx effected --- lower bowel and bladder dysfunction

Injury to Cauda inguina . Maybe due to compression. Leads to Lower Motor Neurone type of paralysis--- Anaesthesia to lower extremity

DearLecturers and Friends

Reference Sincere thanks to lecturers from Anatomy Department of IMS – MSU , Shah Alam. Each of you have helped me

a lot by explaining the concepts and guided my presentation too. Thank you

Dr Mannah – Dr Venu – Dr Gargi – Dr Thim – Dr Ravi

Gratitude