Ventricular System Flashcards
CNS ventricles
*four structures in the brain that contain CSF: 2 lateral ventricles, the third ventricle, and the fourth ventricle
*continuous with the central canal of the spinal cord
pathway of CSF in brain
lateral ventricles -> interventricular foramen -> third ventricle -> cerebral aqueduct -> fourth ventricle -> central canal (of spinal cord)
what ventricle is seen in a cross-section of the midbrain
cerebral aqueduct
what ventricle is seen in a cross-section of the pons
4th ventricle
what ventricle is seen in a cross-section of the medulla
4th ventricle
cerebrospinal fluid (CSF)
*clear, colorless fluid
*acts as a cushion for brain (mechanical protection & shock absorber)
*circulates nutrients & removes waste
CSF production
ependymal cells of the choroid plexus (one in each of the ventricles) produces CSF
CSF absorption
arachnoid villi (granulations) reabsorb CSF, then drain into superior sagittal sinus, and then to venous system (internal jugular vein)
how does the CSF get out of the ventricles and into the subarachnoid space
lateral and median apertures of the 4th ventricles flow CSF into subarachnoid spaces and then into cisterns
superior sagittal sinus
receives CSF from the arachnoid villi
all of the dural sinuses drain into ?
internal jugular vein
is the choroid plexus part of the blood-brain barrier?
YES
pyogenic bacterial meningitis - appearance of CSF
yellowish, turbid
CSF with pyogenic bacterial meningitis -protein
markedly increased
CSF with pyogenic bacterial meningitis - glucose
decreased
viral meningitis - appearance of CSF
clear fluid
CSF with viral meningitis - polymorphonuclear cells
slightly increased or normal
CSF with viral meningitis - lymphocytes
markedly increased
CSF with viral meningitis - protein
slightly increased or normal
CSF with viral meningitis - glucose
normal
tuberculous meningitis - appearance of CSF
yellowish and viscous
CSF with tuberculous meningitis - polymorphonuclear cells
slightly increased or normal
CSF with tuberculous meningitis - lymphocytes
markedly increased
CSF with tuberculous meningitis - protein
increased
CSF with tuberculous meningitis - glucose
decreased
fungal meningitis - appearance of CSF
yellowish and viscous
CSF with fungal meningitis - polymorphonuclear cells
slightly increased or normal
CSF with fungal meningitis - lymphocytes
markedly increased
CSF with fungal meningitis - protein
slightly increased or normal
CSF with fungal meningitis - glucose
normal or decreased
hydrocephalus
*characterized by an excessive amount of cerebrospinal fluid, resulting in :
-ventricular dilation
-increased intracranial pressure (ICP)
*can be congenital or acquired
communicating hydrocephalus
primarily a failure to REABSORB CSF (inability to get CSF into venous system)
obstructive (non-communicating) hydrocephalus
due to the STRUCTURAL BLOCKAGE of ventricular system (ex. blockage of cerebral aqueduct)
CSF with pyogenic bacterial meningitis - lymphocytes
slightly increased or normal
CSF with pyogenic bacterial meningitis - polymorphonuclear cells
markedly increased
