Flashcards in Meningeal Coverings and CSF Deck (34):
What are the 3 layers of the meningeal coverings?
The dura mater is pain sensitive. What innervates these sensory parts?
Front: Trigeminal Nerve
Back: Cervical Nerves
What is the main function of the dura mater?
Provides mechanical strength
What is located beneath the tentorium cerebella?
What is the danger with infections of the skin on the head?
Infections have a chance of spreading to the CNS because blood vessels run from the skin through the skull into the dura mater.
What is the arachnoid mater and its function?
It is thin, avascular, and several layers of cells adhering to the dura and it has its main function as a barrier.
What are the arachnoid trabeculae?
They are strands of collagenous connective tissue and scattered cells and function to suspend the brain.
What is the subarachnoid space?
Space between the arachnoid and the pia mater
How does the CSF enter the venous system?
Through the arachnoid villi
What is the pia mater?
It closely covers the surface of the brain and is very thin
What cells lie directly underneath the pia mater?
Where are the two places where the pia mater thickens?
Where do vessels enter and leave the brain?
Perivascular Space (Virchow-Robin Space)
What holds the spinal cord in place?
What is the cranial epidural space?
There is none in normal cases
What is the spinal epidural space?
It is the space between the periosteum and the dura and it is filled with connective tissue and vertebral venous plexus.
Where do the spinal dura and arachnoid end?
What is a subarachnoid cistern? Where is the large subarachnoid cistern located?
It is a surface irregularity of the arachnoid space. The large cistern is located at the lumbar cistern.
Describe the ventricular system of the brain.
The lateral ventricle is tubular and empties into the 3rd ventricle which is like a slit and it empties into the 4th ventricle which then goes down the central canal.
What connects the lateral ventricle and the 3rd ventricle?
Interventricular Foramen (Foramen of Monro)
What connects the 3rd and 4th ventricle?
Cerebral Aqueduct (Sylvius)
What is the canal of the median aperture and what does it connect?
Canal of Magendie and it connects the 4th ventricle and the subarachnoid space
What is the canal of the lateral aperture and what does it connect?
Canal of Luschka and it connects the 4th ventricle and the subarachnoid space
Where is the CSF made?
What are some important features of the choroid plexus?
It acts as a CSF-blood barrier with the choroid epithelium, which is a specialized ependyma.
What makes up the choroid plexus?
What is the difference between the ependyma and the choroid epithelium?
The choroid epithelium has cells connected by tight junctions that form the CSF-blood barrier
Where is the choroid plexus found?
The choroid plexus occurs near the central ventricles where the pia is close to the choroid epithelium. It is found in all of the ventricular components except for the cerebral aqueduct, frontal horn of the lateral ventricle, and occipital horn of the lateral ventricle.
What are the functions of the CSF?
Mechanically supports the brain by making it lighter.
Acts as a medium for neuroactive hormones to travel through.
What is the most common cause of hydrocephalus?
Malfunction in the resorption of CSF
What is a sensory circumventricular organ?
What is a secretory circumventricular organ?
What are tanycytes?
They are specialized ependymal cells that overlie circumventricular organs; barrier between organ and ventricular CSF