Raised intracranial pressure

Question 1

what is raised intracranial pressure

Answer 1

increased pressure within the cranial cavity

Question 2

what can cause an increase in intracranial pressure

Answer 2

fluid surrounding the brain, due to brain tumour, head injury, hydrocephalus, meningitis, stroke

Question 3

what 2 organs (kind of) can be damaged by raised intracranial pressure

Answer 3

spinal cord and brain

Question 4

what factors make up the intracranial volume

Answer 4

brain, blood, CSF, other components

Question 5

can the cranial cavity expand?

Answer 5

no- thus increase in pressure causes damage to tissues, herniation and constriction of blood vessels

Question 6

what symptoms do 65-75% of patients present with in ICP

Answer 6

transient blurred vision, double vision, loss of vision, papilloedema, pupillary changes

Question 7

what is the sing called where patients with hydrocephalus cannot look up

Answer 7

sunset sign

Question 8

why does vision problems arise with increased intracranial pressure

Answer 8

compression of the optic nerve

Question 9

what are th optic nerves covered in?

Answer 9

meninges

Question 10

what are the 3 layers of the meninges

Answer 10

dura, arachnoid and pia

Question 11

what is the space called between arachnoid and pia

Answer 11

sub- arachnoid space

Question 12

what is enclosed between the dura layers?

Answer 12

dural venous sinuses

Question 13

what cranial nerve supplies the dura mater?

Answer 13

CN V

Question 14

what is contained within the subarachnoid space?

Answer 14

blood vessels and CSF

Question 15

what does the pia layer attach on to

Answer 15

brain + vessels/ nerves

Question 16

what does the subarachnoid space surround?

Answer 16

brain and spinal cord

Question 17

where is CSF produced within the brain?

Answer 17

choroid plexus of the ventricles

Question 18

where is the CSF reabsorbed after being made in the choroid plexus of the ventricles

Answer 18

dural venous sinuses via arachnoid granulations

Question 19

what procedure can be used to access the sub arachnoid space

Answer 19

lumbar puncture at L3/4 or L4/5

Question 20

what does the cerebral aqueduct do

Answer 20

connects the 3rd and 4th ventricles in the midline

Question 21

where is the 4th ventricle

Answer 21

between the cerebellum and the pons

Question 22

where is the 3rd ventricle?

Answer 22

in the midline within the diencephalon

Question 23

what are the laterals and 3rd ventricles connected by

Answer 23

foramen of Munro

Question 24

what 2 things does the CSF drain into

Answer 24

central canal and subarachnoid cisterns

Question 25

what is the circulation of CSF in 8 steps

Answer 25

1- made in the choroid plexus in lateral and 3rd ventricles
2- then drain into right and left lateral ventricles
3- then the 3rd ventricle
then the cerebral aqueduct
4th ventricle
6- pass into central canal or subarachnoid cisterns/ space
7- then reabsorbed from subarachnoid space through arachnoid granulations
8- drain into dural venous sinuses

Question 26

what 3 things will be compressed in the eye due to ICP

Answer 26

optic nerve, central artery and vein of retina

Question 27

how could the oculomotor nerve be damaged

Answer 27

compression and tectorial herniation

Question 28

what 4 muscles does the oculomotor nerve supply

Answer 28

medial recuts, superior rectus, inferior rectus, inferior oblique

Question 29

is oculomotor nerve sympathetic or parasympathetic

Answer 29

parasympathetic (3,7,9,10)

Question 30

if paralysis of oculomotor nerve, will the pupil be dilated or constricted?

Answer 30

dilated

Question 31

so if oculomotor nerve is damaged, what eye position would the eye rest in

Answer 31

down and out (lateral rectus and superior oblique)

Question 32

what muscle would cause ptosis

Answer 32

levator palpebrae superioris

Question 33

what nerve would be damaged in paralysis of superior oblique

Answer 33

trochlear

Question 34

what eye position can the eye not be in when superior oblique paralysis is present

Answer 34

inferomedial

Question 35

what would you get in trochlear nerve palsy when trying to look down?

Answer 35

diplopia