Support Systems: Cerebrospinal Fluid System Vascular Supply Flashcards
Support Systems: CFS System and Vascular Supply
Three layers of meninges cover the brain and spinal cord include?
- Dura mater = Surrounds the brain and consists of an outer layer firmly bound to the inside of the skull and an inner layer, layers are fused together except at the dural sinuses, which are spaces for collection of venous blood and CSF.
- Arachnoid = Is a delicate membrane loosely attached to the dura. Projections of arachnoid form arachnoid villi, pierce the dura and protrude into the venous sinuses, clusters of arachnoid villi form arachnoid granulations, they allow CSF to flow into the sinuses.
- Pia mater = Innermost layer, is tightly apposed to the surfaces of the brain and spinal cord. Subarachnoid space (between arachnoid and dura), is filled with CSF
Three spaces: subdural (between dura and arachnoid), epidural (between skull and dura) and subarachnoid (between arachnoid and pia).
Support Systems: CFS System and Vascular Supply
The CSF-filled spaces inside the brain form a system of four ventricles = ?
- Pair of lateral ventricles = (C shaped) located in the cerebral hemispheres.
- Pair of lateral ventricles = “”
- Third ventricle = narrow slit in the midline of diencephalon.
- Fourth ventricle = located posterior to the pons and medulla and anterior to the cerebellum.
Support Systems: CFS System and Vascular Supply
What ventricle?
Pair of Lateral ventricles = (C shaped) located in the cerebral hemispheres.
* Consist of a body; an atrium; and the anterior, posterior, and inferior horns.
* Lateral ventricles are connected to the third ventricle by the interventricular foramina (or foramina of Monro).
- (Purple) = Posterior horn of lateral ventricle
- (Green) = Anterior horn of lateral ventricle
- (Red) = Inferior horn of lateral ventricle
- (Pink) = Lateral ventricle
Support Systems: CFS System and Vascular Supply
What ventricle?
Third Ventricle = is a narrow slit in the midline of diencephalon.
- Third and fourth ventricles are connected by the cerebral aqueduct.
Support Systems: CFS System and Vascular Supply
What ventricle?
Fouth Ventricle = Is located posterior to the pons and medulla and anterior to the cerebellum.
- 4th ventricle continues through the spinal cord as the central canal
- 4th ventricle drains into subarachnoid space via 3 small openings:
- 2 lateral openings (foramina of Luschka) and a
- midline opening (foramina of Magendie)
Support Systems: CFS System and Vascular Supply
What structure?
Cerebral Aqueduct = Third and fourth ventricles are connected by the cerebral aqueduct.
Support Systems: CFS System and Vascular Supply
Describe CFS formation and circulation.
- Most CSF is secreted by choroid plexuses (a network of capillaries) while some is formed by extracellular fluid leaking into the ventricles.
- CSF is formed from blood by filtration, active transport, and facilitated transport of certain substances, results in formation of fluid similar to plasma.
CSF flows from:
- Lateral ventricles into third ventricle via interventricular foramina.
- Third ventricle into the fourth ventricle via the cerebral aqueduct.
- CSF exits the fourth ventricle, and enters the subarachnoid space via lateral & medial foramina
- Flows around the brain and spinal cord within subarachnoid space.
- CSF is absorbed into the venous sinuses via arachnoid ville (or granulations, which project through the dura into the venous sinuses).
Support Systems: CFS System and Vascular Supply
Indentify
green
Choroid Plexus = a network of capillaries.
- Most CSF is secreted by choroid plexuses (a network of capillaries) while some CSF formed by extracellular fluid leaking into the ventricles.
Support Systems: CFS System and Vascular Supply
Indentify x 3
- Green = ?
- Blue = ?
- Orange = ?
- Green = Lateral Ventricle = CFS flows from lateral ventricles into third ventricle via interventricular foramina
- Blue = Third Ventricle = From the third ventricle into the fourth ventricle via the cerebral aqueduct.
- Orange = Fourth Ventricle = CSF exits the fourth ventricle, and enters the subarachnoid space via lateral & medial foramina.
Support Systems: CFS System and Vascular Supply
CSF is primarily formed in the = ? , and circulates through the ventricles and into the = ?
CSF is primarily formed in the ventricles; circulates through the ventricles and into the subarachnoid space (between arachnoid & pia maters) before being absorbed into the venous circulation.
Support Systems: CFS System and Vascular Supply
CSF protects the _ ? _ and regulates _ ? _ .
- Protects CNS by absorbing some physical/mechanical impact (cushion).
- Regulates the content of extracellular fluid; CFS supplies water, certain amino acids, vitamins, proteins and specific ions to extracellular fluid and removes metabolites from the brain.
Support Systems: CFS System and Vascular Supply
What artery?
blue
Blood supply to the brain
Internal carotid artery = Anterior Circulation
Support Systems: CFS System and Vascular Supply
What artery?
blue
Blood supply to the brain
Vertebral Artery = Posterior Circulation
Support Systems: CFS System and Vascular Supply
Identify
pink
Internal carotid artery
Support Systems: CFS System and Vascular Supply
Identify
pink
external carotid artery
Support Systems: CFS System and Vascular Supply
Identify
pink
right common carotid