ventricles, meninges, BBB, spinal cord Flashcards
how many ventricles in the brain and what are they?
4 ventricles
- 2 lateral ventricles
- 3rd ventricle
- 4th ventricle
features of ventricles of the brain
- fluid filled spaces within the brain
- formed from canal of embryonic tube
- contain CSF
- protect and support brain
where do lateral ventricles lie
below corpus callosum
body and three horns of lateral ventricles
- anterior - frontal lobe
- posterior - occipital lobe
- inferior - temporal lobe
shape of lateral ventricles
paired c-shaped chambers in each cerebral hemisphere
what does the lateral ventricle communicate with
communicates with 3rd ventricle through foramen of monroe
what is the shape of the 4th ventricle and where is it located
- diamond shaped
- located in midline of front of cerebellum and behind pons
- inferiorly continuous with central canal
- superiorly + posteriorly = 3 foramina
what does the 4th ventricle link to
subarachnoid space
what is cerebrospinal fluid
- clear colourless transparent tissue fluid
what is cerebrospinal fluid (CSF) present in
- cerebral ventricles
- spinal canal
- subarachnoid spaces
composition of CSF
- glucose
- proteins
- lipids
- electrolytes
total quantity of CSF
150 ml
functions of CSF
- shock absorber
- cushions brain and spinal cord
- acts as reservoir + regulates content of CNS
- keeps brain and spinal cord moist
- facilitate exchange of nutrients of CNS - transports hormones and hormone releasing factors
- removes metabolic waste products
how is CSF produced
- secreted by specialized ependymal lining of choroid plexus
- released into ventricular system
- fills ventricles
- central canal of spine
- subarachnoid space
what happens to CSF in the subarachnoid space
- eventually reabsorbed through outpouchings into superior sagittal sinus (SSS)
- aka arachnoid granulations
related pathologies to CSF
- meningitis
- hydrocephalus
- CSF leak
- subarachnoid haemorrhage
- lumbar puncture
where is lumbar puncture on the spine
L3/4
what are meninges
3 layers of membranes that cover brain and spinal cord
what are meninges
3 layers of membranes that cover brain and spinal cord
what are the meninges made of
- dura mater
- arachnoid mater
- pia mater
what is the blood brain barrier
a semipermeable membrane which acts as a physiological separation of circulating blood from tissues
4 types of intracranial bleeds
- extradural
- subdural
- subarachnoid
- intracerebral
what are the 3 layers of the blood brain barrier
- endothelia
- basement membrane
- astrocytes
what are the functions of the blood brain barrier
- managing the microenvironment
- regulates entry of nutrients
- regulates exist of wastes
- regulates passage of ions + fluids
