Papilloedema

Question 1

what is papilloedema

Answer 1

swollen optic discs secondary to raised intracranial pressure

Question 2

what should you suspect in a patient with bilateral optic disc swelling

Answer 2

papilloedema due to space occupying lesion until proven otherwise

raised ICP is a medical emergency

Question 3

how do you exam cranial nerve II

Answer 3

opthalmoscopy 
visual acuity 
pupil exam 
visual field assessment 
colour vision

Question 4

what covers the optic nerves

Answer 4

meninges- extension of the brain

Question 5

what is the pathophysiology of papilloedema

Answer 5

subarachnoid space around the optic nerve is continuous with the subarachnoid space surrounding the brain

when intracranial pressure increases this is transmitted to the SAS then on the the ON

this causes unterruption of axoplasmic flow and venous congestion= swollen discs

Question 6

what is the monro- kellie hypothesis

Answer 6

an increase in one variable (either the brain, blood of CSF) will cause a decrease in one/both other variables as cranium is ridgid and cannot expand

Question 7

what happens when ICP rises

Answer 7

when a mass expands compensatory mechanisms maintain a normal pressure

further increases in volume cause blood vessels to be compressed, global brain ischaemia/ swelling with herniation though foramen magnum, brainstem compression and death

Question 8

what are the three components of intracranial pressure

Answer 8

brain (80%)
blood (10%)
(CSF (10%)

Question 9

what is the importance of cerebral blood flow

Answer 9

brain is very intolerant of hypo/hyperperfusion

auto regulation maintains a constant flow of blood despite changes in perfusion pressure

Question 10

what is malignant hypertension

Answer 10

extremely high hypertension- can cause papilloedema

Question 11

how does hypertension cause papilloedema

Answer 11

leakage and ischaemia of arterioles surrounding the optic disc

Question 12

what are the functions of CSF

Answer 12

maintains stable extracellular environment for the brain 
buoyancy 
mechanical protection 
waste removal 
nutrition

Question 13

what is the choroid plexus

Answer 13

network of capillaries which filter blood to form CSF

Question 14

what is the path of CSF

Answer 14

produced in lateral ventricles by choroid plexus

travels through 3rd and 4th ventricles into subarachnoid space

Question 15

what CSF problems can cause ICP to increase

Answer 15

obstruction to CSF circulation
over production of CSF
inadequate absorption

idiopathic intracranial hypertension

Question 16

what test shoes CSF opening pressure

Answer 16

lumbar puncture

Question 17

what happens if disc swelling is chronic

Answer 17

disc swelling subsides, discs become atrophic and pale

loss of visual function occurs and blindness may result

Question 18

what test detects disc swelling

Answer 18

opthalmoscopy

Question 19

what should you always test in swollen discs

Answer 19

blood pressure