Meninges and Ventricular System Flashcards
(19 cards)
what are the 3 meninges layers of the brain
- Dura mater
- Arachnoid
- Pia mater
what are 5 features of dura mater
- outer most layer of meninges
- dense and fibrous
- consists of 2 layers
- space between the layers forms venous sinuses - only in some places
- inner layer forms Dural folds
what are 3 features of Dural folds
- formed from inner layer of dura mater
- separate major divisions of the brain
- provide stability of brain within cranium
what are the 3 Dura folds
- falx cerebri
- separates cerebral hemispheres
- median plane - falx cerebelli
- separates cerebellar hemispheres
- median plane - tentorium cerebelli
- separates cerebrum from cerebellum
- horizontal plane
what are 3 features of venous sinus
- located where the 2 layers of dura mater separate
- collecting veins
- they collect 2 things
- venous blood from the brain
- old cerebrospinal fluid after it has cycled through the ventricular system
what are 5 features of the arachnoid layer
- layer beneath the dura mater
- layer above the pia mater
- does not extend into sulci
- contains 3 special features
- subarachnoid space
- arachnoid granulations
- arachnoid trabeculae - contains blood vessels which is within the subarachnoid space, lying on top of pia mater
what is the subarachnoid space
the space between the arachnoid and the pia mater
- the outer layer of arachnoid is bound with tight junctions
- filled with cerebrospinal fluid
what are arachnoid trabeculae
delicate, spider-web-like strands of connective tissue that span the subarachnoid space, connecting the arachnoid and pia mater, the two innermost layers of the meninges
what are arachnoid granulations
small projections of the arachnoid membrane that protrude (penetrate) into the Dural sinuses, allowing cerebrospinal fluid (CSF) to drain into the venous system
what are the 4 features of pia mater
- inner layer of the meninges
- transparent and delicate
- blood vessels in arachnoid sit on top of pia mater
- adheres to brain and follows gyri and extends into sulci
what are the 4 features of the ventricular system
- network of interconnected spaces (ventricles) within the brain
- filled with cerebrospinal fluid
- spaces lined with ependymal cells which circulate the CSF
- CSF is produced by the choroid plexus
what are the 5 compartments of the ventricular system
- lateral ventricles
- third ventricle
- cerebral aqueduct
- fourth ventricle
- central canal
where are the lateral ventricles
there are 2, one in each of the cerebral hemispheres
where is the 3rd ventricle
located in the diencephalon
where is the cerebral aqueduct
located in the midbrain where it connects the 3rd and 4th ventricle
where is the 4th ventricle
located at the level of the cerebellum
what are the 4 features of cerebrospinal fluid
- produced by choroid plexus within the ventricles
- surrounds the CNS within the subarachnoid space
- provides support and cushion
- transports nutrients and waste
how is CSF generated by the choroid plexus
- epithelial cells of the choroid plexus make up the blood/CSF barrier
- villi of these cells help push the CSF around
what is the circulation path of CSF
starts at lateral ventricles then goes
- 3rd ventricle
- cerebral aqueduct
- 4th ventricle
- subarachnoid space where it flows around brain and spinal cord
exits through arachnoid granulations into venous sinus
