div style=”display:none;”>

Meninges and Compartments

Main Text

TERMINOLOGY

Definitions

• Meninges = collective term for dura, arachnoid, pia

Pachy (“thick”) meninges = dura

Lepto (“thin”) meninges = arachnoid, pia
• Spaces = real or potential spaces between meningeal layers or adjacent structures
• Ligaments = suspend spinal cord within thecal sac
• Compartments = anatomic construct for location-based imaging differential diagnoses

GROSS ANATOMY

Overview

• Meninges

Dura

– Dense, tough outermost layer of connective tissue

– Only 1 dural layer in spine

– Attached by fibrous bands to posterior longitudinal ligament

– Tubular prolongations (nerve sheaths) of dura/arachnoid extend around roots/nerves through intervertebral foramina, terminate near dorsal root ganglia (DRG)

– Dura fuses with epineurium of spinal nerves distal to DRG

Arachnoid

– Thin, delicate, continuous with cranial arachnoid

– 2 layers: Outer (loosely attached to dura), intermediate (attached to pia)

Pia

– Delicate, innermost layer of meninges

– Closely applied to cord, spinal nerves
• Ligaments

Denticulate ligaments

– Flat, fibrous, serrated sheets that support spinal cord

– Collagenous core is continuous with pia

– Extend laterally from pia along each side of cord, between ventral/dorsal roots

– Insert into dura mater

Dorsal, dorsolateral, ventral spinal cord ligaments

– Thin, irregular, fenestrated; extend from cord to arachnoid

Septum posticum

– Incomplete longitudinal midline membrane

– Connects pia/cord dorsally to dura

– Partially divides subarachnoid space (SAS), creating “pseudocompartments”
• Spaces

Epidural space (extradural compartment)

– Between dura and surrounding vertebral canal

– Extends from foramen magnum to posterior sacrococcygeal ligament

– Contains fat, loose connective tissue, small arteries, veins, lymphatics

Subdural space

– Potential space between dura, outer surface of arachnoid

SAS

– Between inner surface of arachnoid, pia

– Contains CSF, vessels, spinal cord ligaments, nerves, filum terminale

– Continuous with intracranial SAS

Subpial space (potential space only)
• Compartments

Extradural compartment

– Epidural space

– Vertebral bodies, neural arches, intervertebral discs, paraspinous muscles

Intradural extramedullary compartment

– SAS

– Spinal cord ligaments, nerve roots, cauda equina, filum terminale

Intramedullary compartment

– Spinal cord, pia

IMAGING ANATOMY

Overview

• Meninges

Dura

– Thin black line on T2WI

– Vessels lack endothelial tight junctions so dura enhances strongly, uniformly

Only gold members can continue reading. Log In or Register to continue

Share this:
X
Facebook

Related posts:

Frontal Pole (Area 10) Intracranial Venous System Overview Inferior Parietal Lobule (Areas 39, 40) Attention Control Network Medulla Ventricles and Choroid Plexus

Stay updated, free articles. Join our Telegram channel

Tags: Imaging Anatomy Brain and Spine

Mar 13, 2021 | Posted by admin in NUCLEAR MEDICINE | Comments Off

Main Text

TERMINOLOGY

Definitions

GROSS ANATOMY

Overview

IMAGING ANATOMY

Overview

Stay updated, free articles. Join our Telegram channel

Radiology Key

Fastest Radiology Insight Engine

Meninges and Compartments

Meninges and Compartments

Full access? Get Clinical Tree

Fastest Radiology Insight Engine

Meninges and Compartments

Share this:

Related posts:

Stay updated, free articles. Join our Telegram channel

Full access? Get Clinical Tree