Extra Neuro Flashcards
Where is CSF made?
in the choroid plexus
Define hydrocephalus?
Excessive volume of CSF in ventricular system
Define the 2 main groups of hydrocephalus?
obstructive (non-communicating) - physical blockage to the flow of CSF
non obstructive (communicating) - imbalance in resorption or production of CSF
Describe examples of obstructive (non-communicating) hydrocephalus?
congenital anomalies:
congenital stenosis or atresia of the Sylvian aqueduct
atresia of the foramen of luschka or magendie
arnold chiari malformation (may be associated with spina bifida)
acquired:
posterior fossa and brainstem tumours
3rd ventricle colloid cyst
choroid plexus papilloma (rare)
What is Arnold Chiari malformation?
part of the cerebellum and medulla bulges through the foramen magnum
Describe examples of non-obstructive (communicating) hydrocephalus?
Descreased resorption e.g. meningitis or post haemorrhage
increased production - choroid plexus tumour (very rare)
Presentation of hydrocephalus in infants?
since sutures are not fused there is an increase in head circumference, failure of upward gaze and sunsetting eyes
Presentation of hydrocephalus in adults?
causes raised ICP so presents with headache with red flags, papilloedema, nausea and vomiting, coma
Investigations for hydrocephalus?
CT head
MRI
Lumbar puncture can be both diagnostic and therapeutic since it allows sampling of the CSF, measuring of opening pressure but also to drain and reduce some of the pressure
Management of hydrocephalus?
treat underlying cause
external ventricular drains
ventriculoperitoneal shunting
Cause of normal pressure hydrocephalus?
mainly unknown
Define normal pressure hydrocephalus?
non obstructive hydrocephalus characterised by large ventricles with normal intracranial pressure
Presentation of normal pressure hydrocephalus?
triad of gait disturbance, dementia and urinary incontinence
Management of normal pressure hydrocephalus?
ventriculoperitoneal shunt
What is syringomyelia / syringobulbia?
can be called syrinx for shot
collection of CSF in the spinal cord
if in the medulla it is called synrigobulbia
Causes of syringomyelia?
strong association with arnold chiari malformation
trauma, tumours, idiopathic
Presentation of syringomyelia?
cape like loss of temperature sensations, spastic weakness, in LL
upgoing planters
Investigations for syringomyelia?
MRI whole spine and brain (to rule out arnold chiari malformation)
Investigations for syringomyelia?
MRI whole spine and brain (to rule out arnold chiari malformation)
Management of syringomyelia?
may need a shunt
C5 Dermatome?
Badge patch
C6 Dermatome?
Thumb
C7 Dermatome?
middle finger
C8 Dermatome?
pinky
T1 Dermatome?
above and below elbow on anterior arm
T2 Dermatome?
medial top of arm
T3 Dermatome?
Just above the nipple
T4 Dermatome?
in line with the nipple
T10 Dermatome?
At the umbilicus
L1 dermatome?
at the groin
L2 Dermatome?
upper anterior thigh
L3 dermatome?
Knee
L4 Dermatome?
Medial leg
L5 Dermatome?
Lateral leg and big toe
S1 Dermatome?
pinky toe
Femoral nerve roots?
L2, L3, L4
Sciatic nerve roots?
L4-S3
Sciatic nerve divides into what 2 nerves?
tibial and common peroneal
Anterior compartment of the thigh is supplied by and does what?
Femoral nerve, flexion at the hip, extension at the knee
Posterior compartment of the thigh is supplied by and does what?
tibial nerve, extension at the hip, flexion at the knee
The medial thigh is supplied by what and does what?
obturator nerve, adduction of the thigh
The lateral leg is supplied by what and does what?
superficial peroneal nerve, eversion
Anterior leg is suppled by what and does what?
deep peroneal nerve, dorsiflexion, extend toes, inversion and eversion
Posterior leg is suppled by what and does what?
tibial nerve, plantar flexion of ankle and flexion of toes
Lesion of the femoral nerve means?
won’t be able to flex hip or extend knee
Lesion of sciatic nerve?
lose full leg extension, will get a foot drop
Lesion of common peroneal nerve?
associated with fibula neck fractures, will get a foot drop
lesion of obturator nerve?
loss of adduction
Cutaneous nerve supply to the hand?
ulnar - pinky plus half the ring both sides
radial - dorsal side of hand (dorsal web spaces!) - thumb plus two and half fingers
median nerve - palmar side of hand - thumb plus two and half fingers
Axillary nerve lesion?
dislocation of shoulder
loss of sensation to the badge patch
loss of shoulder abduction
Radial nerve lesion?
wrist drop - humeral shaft fractures (loss of wrist extension)
Median nerve lesions?
carpal tunnel syndrome
Ulnar nerve lesions?
weakness of hand - loss of sensation in digits 4 and 5
Ankle jerk reflex?
S1, S2 (buckle my shoe)
Knee jerk reflex?
L3, L4 (kick the door)
Biceps reflex?
C5, C6 (pick up sticks)
Triceps reflex?
C7, C8 (lay them straight)
Loss of sensation in big toe and no reflexes affected ?
L5
L5 root damage?
loss of big toe sensation and big toe extension
S1 root damage?
loss of ankle plantar flexion, ankle reflex may be affected, loss of sensation in little toe and potentially heel
Hip replacement can damage?
The sciatic nerve
Stenosis
narrowing of canal
lumbar spinal stenosis is the most common cause of neurogenic claudication
Spondylosis
age related wear and tear of the intervertebral discs
can cause a myelopathy or a radiculopathy
Spondylolithesis
vertebra falls forward and pushes on the spinal cord (anterior direction)
Disc prolapse
= disc herniation = slipped disc
IV disc protrudes posteriorly and can compress the spinal cord
Cauda equina syndrome?
syndrome from compression of cauda equine most commonly caused by disc prolapse but could be trauma, tumours, infections, etc
Myelopathy
compression of spinal cord, UMN signs
Radiculopathy
compression of spinal roots LMN signs
What is raised 10-20 minutes after a true seizure?
raised serum prolactin
What is a rare but serious side effect of lamotrigine?
Steven Johnson syndrome
patients must look out for the rash - seek medical help
T1 myotome?
thumb adduction - T1 bring in the thumb
Klumpkes palsy is what type of injurY?
a traction injury
First line for absence seizures?
ethosuximide
