neuro key notes Flashcards
which cranial nerves carry parasympathetic fibres?
1973
10 - Vagus (heart and abdnominal viscera)
9 - Glossopharyngeal (parotid)
7 - Facial (lacrimal gland, submandibular and sublingual)
3 - Oculomotor (pupillary constriction and accommodation)
34 y/o female, severe headache, both sides, blurring vision RHS. RHS papilloedema and CNVI palsy. Hypertensive
classic presentation of:
Idiopathic intracranial hypertension
mneumonic for branches off the posterior cord of the brachial plexus
Andy you’re a….
Subscapular (upper and lower)
Thoracodorsal
Axillary
Radial
Common peroneal nerve lesion
The common peroneal nerve provides sensation and motor function to the lower leg.
When compressed or damaged it can cause foot drop.
Other features include:
1. weakness of foot dorsiflexion
- weakness of foot eversion
- weakness of extensor hallucis longus
- sensory loss over the dorsum of the foot and the lower lateral part of the leg
- wasting of the anterior tibial and peroneal muscles
A young woman presents with right-sided loss of fine-touch and vibration sensation. She also exhibits ipsilateral loss of proprioception. Which anatomical structure has likely been damaged?
- Right Dorsal Column,
- involved in fine touch, vibration sensation and proprioception
- patients symptoms RHS, right dorsal column ipsilateral innervation
Dorsal column lesions commonly caused by
vitamin B12 deficiency
A 48-year-old man presents to the neurology clinic with a right sided intention tremor. He is also found to have right sided dysdiadochokinesia.
Which part of the brain is a lesion most likely to be located?
right cerebellum.
Unilateral cerebellar lesions cause ipsilateral signs. what signs are consistent with cerebellar disease
- unilateral dysdiadochokinesia
- unilateral intention tremor
- patients may appear drunk
- Hypotonia
- Ataxia
- Nystagmus
lesion in basal ganglia would cause patient to likely have
resting tremor
38 y/o unilateral drooping of LHS of mouth, can’t smile LHS. Can frown, lift eyebrows.
asthma and four previous miscarriages, non-smoker, drinks alcohol moderately.
Sparing of forehead: UMN
Stroke
- patient is young, although multiple miscarriages suggestive of anti-phospholipid syndrome which is major risk factor for stroke
innervation of scrotum
anterior and posterior
anterior: ilioinguinal nerve
posterior: pudendal nerve
what cells provide the inner lining of ventricles in brain and are responsible for CSF production?
Ependymal cells
cells important in forming the blood brain barrier
astrocytes
which cells form the myelin sheath in the CNS and which form the myelin sheath in the PNS?
CNS ————–> oligodendrocytes
PNS ————–> schwann cells
what are microglia?
central nervous system macrophage cells.
first line of active immune defence in CNS.
A 43-year-old woman is being reviewed on the ward one day post-op from a thyroidectomy. She has been generally well, but her voice sounds hoarse.
What nerve has been damaged during the surgery?
we know its recurrent laryngeal but is it right or left!
right recurrent laryngeal
—-> crosses neck diagonally
—-> more prone to injury during surgery
eclampasia
high blood pressure in pregnancy
A 53-year-old male attends the neurology clinic with his wife. She tells you that she has noticed changes to his speech over the past four months. She tells you it is loud and jerky and he pauses between syllables. However he is able to understand everything that he hears. When you speak to him, he is able to understand what you say but his speech is jerky with pauses. He has no problems with repetition and you find no weakness or changes to the sensation in any of his limbs. You suspect a lesion in his brain may be causing this pattern of speech.
Lesion in cerebellar disease:
- scanning dysarthria (jerky loud speech with pauses)
- dysdiadochokinesia
- nystagmus
- intention tremor
Lesion in superior temporal gyrus may cause?
Wernicke’s aphasia
- sentences that do not make sense
- comprehension impaired
as opposte to broca’s aphasia
- defective production of language
- intact understanding
Damage to tibial nerve results in
loss of plantar flexion,
loss of flexion of toes
weakened inversion
neuropraxia
nerve intact
but electrical conduction affected
A 31-year-old man presents to the emergency department with left sided chest pain after falling from a ladder whilst doing some DIY. A chest X-ray is ordered and reveals no fractures but an incidental finding of a cervical rib. He is told that this increases his risk of developing thoracic outlet syndrome (TOS).
What is the most accurate information about this condition to relay to the patient?
involves compression of brachial plexus
subclavian artery or vein at the site of thoracic outlet.
vagus nerve passes through what foramen
jugular foramen
A 25-year-old patient presents to GP with wasting of the leg muscles, foot drop, and a high-arched foot. The patient has a past medical history of type 1 diabetes mellitus. The GP notices the patient’s leg resemble ‘champagne bottles’. The patient denies any sensory deficits, recent trauma or back pain.
What is the most likely diagnosis?
Charcot-Marie-Tooth disease
- High arched foot
- foot drop
- chronic —-> muscular atrophy —-> high arched foot and champagne bottle appearance
A patient becomes deplete in one particular hormone and consequently develops cranial diabetes insipidus.
In which part of the hypothalamus is this particular hormone normally secreted?
SADH
ADH produced in the supraoptic nucleus in the hypothalamus
A 54-year-old male, who is known to have high blood pressure, presents with a stroke. On examination, he has right sided facial and arm weakness and an expressive dysphasia. He is diagnosed with a stroke and thrombolysis is arranged. Which artery is most likely to have been occluded?
middle cerebral artery.
if patient RHS affected we know artery is on LHS.
Left middle cerebral!
muscles innervated by radial nerve
you’re the …..
BEST
B- brachioradialis
E - extensors
S - suprinator
T - triceps
damage to anterior interosseous nerve may result in….
- inability to make OK sign
Tinel’s test asses for…
- carpal tunnel compression of the median nerve
During a cranial nerve examination of a 70-year-old male, it is noted that when he is told to stick his tongue out, it deviates to the left.
A lesion of which cranial nerve would produce this sign?
Left hypoglossal.
palsy of hypoglossal nerve causes tongue to deviate towards the site of lesion.
Remember a homonymous hemianopia is indicative of an lesion in the…
optic tract
optic chiam lesion or pituitary tumours lead to…
bitemporal hemianopia
broca’s aphasia due to lesion of the…
inferior frontal gyrus
lesion in primary motor cortex results in
contralateral motor deficit
third nerve palsy results in what
occulomotor palsy
- down and out eye
- ptosis
Features of Klumpkes Paralysis
- claw hand
- loss of sensation over medial aspect of forearm and hand
- Horner’s syndrome
- Loss of flexors of wrist
A middle-aged man presents with progress paralysis and difficulty swallowing. Examination reveals spastic paralysis of the arms and decreased knee reflexes. He is subsequently diagnosed with amyotrophic lateral sclerosis (ALS). Which pattern of cell death explains the mixed upper and lower motor neurone lesion signs observed in ALS?
Motor cortex neuronal damage
—-> upper motor lesions
Anterior horn cell damage
—-> lower motor lesions
Thus mixed signals seen in ALS.
what nerve responsible for pupillary sphincter
oculomotor
A 55-year-old male presents to the emergency department with left sided vision loss, headache and scalp tenderness. On examination, he has a temperature of 38.5°C, jaw claudication and a relative afferent pupillary defect.
A diagnosis of what is made?
Giant cell arteritis.
Ishcaemic optic neuropathy occurs in giant cell arteritis,
calcitonin released from
C cells of thyroid.
inhibits osteoclast activity.
inhibits renal tubular absorption of calcium.
What nerve supplies the external anal sphincter?
inferior rectal branch of the pudendal nerve
A 35-year-old man who was last seen for gastroenteritis 3 weeks ago comes to see you saying that he has noticed that his hands and feet have felt numb and painful since this morning. On examination, he has a reduced power of 3/5 in his upper and lower limbs, bilaterally. His speech is normal. He is usually fit and well and does not suffer from any other medical problems.
Guillain-Barre syndrome
- immune-mediated demyelination of the peripheral nervous system
- triggered by an infection
- presents with ascending motor neuropathy which is often rapidly advancing.
- Proximal muscles are more affected than distal muscles.
transient ischaemic attack
- sudden onset
- unilateral symptoms
- facial droop
- arm weakness
- slurred speech
ALS - amyotrophic lateral sclerosis
- selective degeneration of motor neurons
- progressive muscle weakness and spasticity
Sensation and sensory attention are associated with what lobe?
- associated with parietal lobe
- damage causes contralateral deficitis
intention tremor may be witnessed during what test
- finger to nose test
- feature of cerebellar disease
- other features: ataxia, dysdiadochokinesia
vision worse going down the stairs
4th nerve palsy.
A young man gets into a fight in a bar and is stabbed with a broken bottle in the back and sustains a spinal cord injury where half the spinal cord is cut.
How is pain sensation going to be affected following this injury?
Spinothalamic tract decusates in the spinal cord one level above where the sitmulus enters.
thus loss of pain sensation on opposite side of body below the injury.
What is the most useful test to clinically distinguish between an upper and lower motor neurone lesion of the facial nerve?
options:
a) blow cheeks out
b) loss of chin reflex
c) close eye
d) raise eyebrow
e) open mouth against resistance
Get patient to to raise eyebrows.
Upper motor neuron lesions of facial nerve
———> paralysis of lower half of face
Lower motor neurone lesion of facial nerve
———> paralysis of the entire ipsilateral face
coarse facial appearance, spade-like hands, increase in shoe size, large tongue, prognathism, interdental spaces, excessive sweating and oily skin
acromegaly!
due to growth hormone overproduction
from anterior pituitary
which seizures cause visual changes such as floaters and flashes?
occipital lobe seizure
which seizures can cause hallucinations and automatisms?
temporal lobe seizures
which seizures can cause head/leg movements and post-ictal weakness?
frontal lobe seizures
which seizures can cause paraesthesia?
parietal lobe seizures
A 33-year-old man sustains an injury to his forearm and wrist. When examined in clinic he is unable to adduct his thumb. What is the most likely underlying nerve lesion?
deep branch of ulnar nerve
- inability to adduct thumb
- withdrawing paper between patients hand grasped between thumb and index finger
A 34-year-old man is stabbed in the back causing a hemisection of the spinal cord at the level T5. You assess the patient’s sensory function, with respect to temperature, vibration, fine touch. You also assess the patient’s muscle strength. Which signs would you expect to see?
- contralateral loss of temperature
- ipsilateral loss of fine touch and vibration
- ipsilateral spastic paresis
why is temperature loss contralateral in spinothalamic lesions?
- spinothalamic carries sensory fibres for pain and temp
- decussates at same level the nerve root enters spinal cord
- thus contralateral temperature loss
why is fine touch and vibration loss ipsilateral in dorsal column medial lemniscus lesions?
- DCML carries sensory fibres for fine touch and vibration
- decussates at medulla
- hence fine touch and vibration loss is ipsilateral
which side does lesion in corticospinal tract result in?
- corticospinal is descending tract
- already decussated in medulla
- responsible for inhibitng movement of muscles
- loss of function causes UMNL on ipsilateral side.
triad of wernicke’s encephalopathy
- acute confusion
- ataxia
- opthalmoplegia
- ——> paralysis of muscles surrounding eye
You have been called to see a patient on your ward because the nurse is concerned about his breathing and thinks he may be deteriorating. The patient is 79-years-old. He is responsive to pain only. His respiratory rate is 6 breaths per minute. You note he has pinpoint pupils. The muscle that causes pupil constriction is called constrictor pupillae. The nerve fibres innervating this muscle are derived from which nerve?
oculomotor
A patient presents with difficulties with swallowing, muscle cramps, tiredness and fasciculations. A diagnosis of motor neuron disease is made.
What is the most common type of this condition?
ALS
A 35-year-old male presents to the emergency department with a severe headache which began today. He says the pain is located at the back of his head and is worse when he coughs and leans forward. He has vomited twice and is experiencing some blurred vision. He is sent for an MRI scan which shows a downward herniation of the cerebellar tonsils.
Arnold chiari malformation
downward herniation of cerebellar tonsils through the foramen magnum.
middle cerebral artery is a branch of…
maxillary artery
parkinsons triad
- tremor at rest
- bradykinesia
- rigidity
A 19-year-old patient presents to primary care with loss of sensation in the dorsal web between the 1st and 2nd metacarpals. He spent the entire night sleeping with his arm hanging over the back of a chair.
Which nerve has he most likely compressed?
Radial nerve
‘saturday night palsy’
one arm’s hanging over chair.
compresses radial nerve and causes wrist drop.
