Physiology Flashcards
(39 cards)
what does CSF look like and what is it mainly made of?
clear and colourless, mainly water
large amounts of what in the CSF can indicate pathology
protein, blood etc
where is CSF formed and by what cells
produced by choroidal cells of choroid plexus in the lateral ventricles
where is CSF absorbed intp
venous circulation
what are the 3 main functions of CSF
1) mechanical protection and shock absorption 2) homeostatic function eg pH and hormones 3) circulation and minor exchange of nutrients and waste eg supplies water, amino acids
what is CSF analysis used for and how would you obtain a sample
for diagnosis of brain, meninges and spinal cord - obtain via lumbar puncture
in embryology, what does the CNS arise from
neural canal (week 3)
in embryology, where does the choroid plexus develop from
walls of ventricles
what is the choroid plexus made of and where are they found
made of ependymal cells and capillaries - found in the 4 ventricles of the brain
what is transported in the CSF
Na, Cl and HCO3
describe the circulation of CSF (6)
formed in choroid plexus of lateral ventricles –> flows to 3rd ventricle via inter-ventricular foramina –> 4th ventricle via cerebral aqueduct –> subarachnoid space –> circulates spinal canal –> absorbed via arachnoid granulations to venous blood
what is the function of the blood brain barrier
prevent toxins and infection entering the brain
what are 3 tumours that can arise from the ventricles, choroid plexus and CSF
colloid cysts (inter-ventricular foramen) / ependymomas (ependymal cells of choroid plexus) / choroid plexus tumours
what are 3 types of haemorrhage that can occur in the ventricles, choroid plexus and CSF
epidural (between skull and dura) / subdural (venous bleed between dura and arachnoid) / subarachnoid haemorrhage
what is hydrocephalus and what does it cause
accumulation of CSF in ventricular system or around the brain - causes and increased CSF pressure and swelling
what is idiopathic inter-cranial hypertension
increased CSF pressure but no imaging of hydrocephalus
what is papilloedema
optic disc swelling transmitted to subarachnoid space around optic nerve from raised ICP
what is aqueous humour
specialised fluid in anterior chamber that provides oxygen and metabolites for vascular components of the eye
what secretes aqueous humour
epithelial later of ciliary body
what drains aqueous humour
scleral venous sinus at iridocorneal angle
what 4 things are required for vision
pattern of object what fall onto photoreceptors in retina / light regulation / energy transduction/ reception of electrical signals by brain
what is the pathway light follows from the retina to the optic nerve
hits photoreceptor –> bipolar cells –> ganglion cells –> CNII
what do does the retina convert electromagnetic radiation into
neural signals
what are the regions of the retina
outer segment, inner segment, cell body, synaptic terminal
