Ventricular System And Cerebrospinal Fluid Flashcards
What is the ventricular system continuous with?
Subarachnoid space and central canal
What separates the bodies of the lateral ventricles?
Septum pellucidum, with corpus callosum sitting on the roof
Hippocampus sits in the?
Inferior horn
Caudate nucleus sits in the?
Laterally to the lateral ventricles
How do lateral ventricles communicate with 3rd ventricle?
Interventricular Foramen, also called Foramen of monro
What forms roof of 3rd ventricle?
Fornix
Third ventricle communicates with the 4th ventricle via?
Cerebral aqueduct, aqueduct of Sylvius, surrounded by midbrain
Fourth ventricle is surrounded by?
Hindbrain
Cerebellum posterior
Pons and medulla anterior
Cerebellar peduncles lateral
3 foramina exit into subarachnoid space?
2 foramina of luschka lateral
One Foramen of magendie middle
Into the cisterna manga
CSF is produced by?
Choroid plexus
What does choroid plexus do?
Filters blood from branches of internal carotid and basilar arteries
What is structure of choroid plexus?
Capillary network surrounded by cuboidal epithelium, blood filtered through fenestrated capillaries
What are the tight junctions for?
Prevent macromolecules from entering CSF
What is different about CSF to plasma?
Low protein
Very few leukocytes
Where are arachnoid granulations?
In superior Sagittal sinuses and transverse sinuses
Why is high CSF pressure compared to venous pressure good?
Prevents blood pooling in subarachnoid space
If venous pressure exceeds CSF pressure then?
Tip of arachnoid granulations close off
Volume of CSF produced per day?
600-700 ml
How much fluid in ventricles?
25 ml
How often is CSF replaced a day?
4 times
If CSF is yellow, orange or pink?
Xanthocromia
Subarachnoid haemorrhage, lysis of red blood cells and haemoglobin release
Cloudy turbid CSF?
Bacterial meningitis
Leukocytes increased
Indicative of infection
Where does CSF sampling happen?
Lumbar cistern
L3/4- adults
L4/5 children
Non communicating hydrocephalus?
Blockage within ventricular system, e.g cyst tumour stenosis
Surgery inset shunt to reduce intracranial pressure
Dandy walker syndrome?
Congenital malformation of cerebellum, 1:30,000 births
Obstruction within foramina of 4th ventricle, dilation of lateral ventricle, 3rd and 4th
Communicating hydrocephalus?
Obstruction in arachnoid villi, movement of CSF into venous sinuses is impeded
E.g impaired absorption following subarachnoid haemorrhage trauma or bacterial meningitis
