Anatomy of raised ICP Flashcards
What are some causes of raised ICP?
head injury
space occupying lesion - tumour, abscess
hydrocephalus (blockage of CSF circulation)
meningitis
What are the meninges?
layers that surround the brain
List the meninges from skul -> brain?
dura mater
arachnoid mater
pia mater
What is contained in the dura mater?
venous sinuses - pools of venous blood
What is contained in the arachnoid mater?
arachnoid-vili - how CSF is drained
What passes through the tentorial notch?
the brainstem
in the dura mater
What are ventricles?
holes filled with CSF
What are the symptoms of a raised ICP?
transient blurred vision double vision loss of vision pupillary changes papilloedema
What will be compressed alongside the optic nerve?
artery and vein
What is the optic nerve covered by?
subarachnoid space
What cranial nerve is the oculomotor nerve?
CN III
What is the oculomotor nerve damaged by?
compression tentorial herniation aneurysms (posterior communicating aneurysm) MS congenital
What the sign of a damaged CN III?
eye looks down and out
ptosis
What does a fixed dilated pupil indicate?
BAD sign
What does CN III supply?
somatic motor to the extra ocular muscles
parasympathetic control to the constrictor pupillae
What cranial nerve is the trochlear nerve?
CN IV
What causes CN IV damage?
tumour
stretching
What is the characteristic sign of a compensated CN IV problem?
head tilt
What does CN IV problems cause?
paralysis of the superior oblique
eye cannot move in and down
double vision when looking down
What is the presentation of a decompensated CN IV problem?
double vision
What cranial nerve is the abducens nerve?
CN VI
What can damage CN VI?
papilodema stretch tumour microvascular congential IMPINGEMENT - BILATERAL PALSY
What does damage to CN VI cause?
paralysis of the lateral rectus
eye cannot move laterally, resulting in a medial deviation of the eye
What can the CN VI become impinged on?
outer petrous tip in the brain
What is inter nuclear opthamopia?
problem with the gray matter in the brainstem - not the actual nerves themselves
What are the sign of inter nuclear opthamopia?
If the problem is on the left: eyes will try to look to the left, right eye will look to the left, left eye will look straight ahead but you will see the twitching of the left eye
What are the causes of inter nuclear opthamopia?
MS
stroke
vascular
