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Amir Sam DPD 2018 > DPD 4 - Neuro > Flashcards

Flashcards in DPD 4 - Neuro Deck (54)
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1

A 59 y/o man presents w/ exertional chest pain. He has long standing HTN and has a normal ECG. O/E: Frank's sign. What is the most likely diagnosis?
1. Coronary artery stenosis
2. Musculoskeletal
3. Pericarditis
4. Relapsing polychrondritis
5. Vasculitis

Coronary artery stenosis
Note that this is exertional chest pain. Frank's sign is a diagonal crease in ear lobe extending from the tragus across the lobule to the rear edge of the auricle and is assoc. w/ ischaemic heart disease. Indicative of CVD and/or diabetes.

2

What can be seen in a UMN lesion e.g. brain tumour, specifically regarding the tone, power + reflex?

Increased tone = spasticity - reduced central descending inhibition
Decreased power
Increased reflexes = brisk + upgoing plantars

3

What can be seen in a LMN lesion, specifically regarding the tone, power + reflex?

Decreased tone = flaccid
Decreased power
Decreased reflexes

4

An IVDU presents w/ slurred speech, dysphagia, diplopia, bilateral ptosis + has a sluggish pupillary response to light. He has descending symmetric muscle weakness + multiple skin abscesses on arms + legs. Where is the issue likely to be located anatomically?
1. Brain
2. Brainstem
3. Spinal cord
4. Nerve root
5. NMJ

NMJ
Unlikely to be in the brainstem as this would mean CN 3/4/6/9/10/11 would be knocked off so he would be dead. This is likely to be a diffuse neuromusular issue due to the diplopia and dysphagia so a NMJ issue is likely. The multiple abscesses suggests that he has run out of veins and this is an example of skin popping (injecting heroin under the skin). Infected heroin results in causing abscess infected with Botulinum toxin - this inhibits ACh release hence NMJ issue

5

Name 5 cerebellar signs to do with coordination.

Ataxia = uncoordinated movements
Nystagmus
Dysdiadochokinesia = rapidly alternating movement
Intention tremor = dysmetria + pass pointing on the finger-nose-finger test
Speech = slurred, scanning

6

What can cause a cerebellar lesion? (x 5)

Remember V, 2 I's and 2 T's
Vascular - Bleed
Infection - TB, VZV, cerebellitis
Inflammation - MS
Tumour - Primary, secondary mets
Toxin - alcohol, phenytoin

7

A pt presents w/ a hemisensory loss, where is the damage likely to be?
1. Cerebral cortex
2. Spinal cord
3. Nerve roots
4. Mononeuropathy
5. Polyneuropathy

Cerebral cortex
Hemisensory loss = different between L and R side

8

A pt presents w/ a sensory loss around the umbilicus. Where is the damage likely to be?
1. Cerebral cortex
2. Spinal cord
3. Nerve roots
4. Mononeuropathy
5. Polyneuropathy

Spinal cord - the distribution loss is at the same level i.e. difference at particular level

9

A pt presents w/ sensory loss in the lateral side of their outer thigh. Where is the damage likely to be?
1. Cerebral cortex
2. Spinal cord
3. Nerve roots
4. Mononeuropathy
5. Polyneuropathy

Nerve roots (radiculopathy) as it is a dermatomal distribution

10

A pt presents w/ sensory loss of their lateral three fingers in the right hand. Where is the damage likely to be?
1. Cerebral cortex
2. Spinal cord
3. Nerve roots
4. Mononeuropathy
5. Polyneuropathy

Mononeuropathy - specific area e.g. median nerve in CTS

11

A diabetic pt presents w/ sensory loss in their feet and fingers. Where is the damage likely to be?
1. Cerebral cortex
2. Spinal cord
3. Nerve roots
4. Mononeuropathy
5. Polyneuropathy

Polyneuropathy - glove + stocking distribution e.g. diabetic neuropathy

12

A 55 y/o man presents w/ numbness + tingling in hands and feet. PMHx: T1DM. DHx: On basal/bolus insulin. Ix: HbA1c 50 mmol/mol; B12: 500 PG/ML (200-900); eGFR: 90. There is decreased sensation to peripheries (glove + stocking distribution). What would you prescribe? (Not essential)
1. Codeine
2. Duloxetine
3. Hydroxocobalamin
4. Paracetamol
5. Pregabalin

Pregabalin for peripheral neuropathy

13

What are the causes of peripheral neuropathy? (x 6 broad categories)

1. Infection e.g. HIV
2. Inflammation/Autoimmune e.g. GB syndrome (= acute inflammatory demyelinating polyneuropathy assoc. w/ campylobacter jejuni infection); chronic inflammatory demyelinating polyneuropathy; CTD; Vasculitis
3. Toxin e.g. alcohol, cisplatin, amiodarone, metronidazole etc
4. Metabolic e.g. diabetes, B12 deficiency, amyloidosis, chronic kidney disease
5. Hereditary e.g. hereditary sensory motor neuropathy - pes cavus due to long standing peripheral neuropathy. A prominent example of this is Charcot-Marie-Tooth disease

14

What Ix would you do if you suspected alcohol was the cause of peripheral neuropathy?

Hx
Raised GGT
Raised MCV

15

What Ix would you do if you suspected B12 deficiency was the cause of peripheral neuropathy?

FBC to look for anaemia
Increased MCV - macrocytic anaemia
Serum B12

16

Define amyloidosis

Deposition of abnormal protein in various organs which affects the function. These abnormal proteins have precursors.

17

What are the 2 types of amyloidosis?

1. Amyloidosis w/ myeloma: myeloma = increased production of immunoglobulin w/ light chain. These light chains become the precursors of amyloid fibrils
2 Chronic infection/inflammation: serum amyloid A is an inflammatory protein

18

A 34 y/o woman presents w/ weakness in the legs + blurred vision. She has increased tone + hyperreflexia but decreased power and pinprick sensation in the legs. Fundoscopy shows an ill-defined optic disc. What is the cause of her blurred vision?
1. Amaurosis fugax
2. Anterior uveitis
3. Papilloedema
4. Papillitis
5. Vitreous haemorrhage

Papillitis = optic neuritis = inflammation of head of optic nerve
This is associated w/ pain on eye movements + blurred vision + demyelination e.g. multiple sclerosis.
Papilloedema also has a blurred optic disc on fundoscopy but is due to increased ICP + is not painful
Her weak legs suggests lesions affecting the spinal root - spastic paraparesis = increased tone w/ weak legs

19

What would a lesion in the corticospinal tract cause?

Weakness, hyperreflexia + upgoing plantars - the descending motor pathway is in the corticospinal tract so a lesion would result in weakness. These pathways are inhibitory therefore lesion results in increased brisk reflexes + upgoing plantars

20

What would a lesion in the spinothalamic tract cause?

Loss of sensation to a level. The spinothalamic tract is the ascending sensory tract therefore a lesion would result in loss of sensation

21

Give examples of pathology of the spinal cord (x 4 main ones)

1. Spinal cord compression
2. Vascular e.g. defect of anterior spinal artery
3. Infection e.g. Pott's disease (TB of the spine)
4. Inflammation (demyelination) e.g. transverse myelitis = inflammation of spinal cord assoc. w/ mycoplasma pneumonia
Other causes include:
- Toxic/metabolic: subacute combined demyelination of the spinal cord
- Tumour/malignancy: primary or secondary spinal metastasis/spinal cord tumour

22

Describe generally the presentation of multiple sclerosis

2 lesions; separated in TIME + SPACE
e.g. papillitis - optic nerve affected; spinal cord lesion - weakness

23

A 60 y/o man presents w/ pain + paraesthesia on anteriolateral thigh. PMHx: T2DM. DHx: Metformin. Ix: HbA1c: 60 mmol/mol; BMI: 30 kg/m^2. O/E: Decreased pinprick sensation on anterolateral thigh. What is the most appropriate next step in his management?
1. Lose weight
2. Insulin
3. Statin
4. Aspirin
5. MRI brain

Lose weight
First, you need to identify where the issue is. The dermatomal distribution suggests it is in the nerve roots (radiculopathy) so MRI brain is not needed because lesion is not in the brain. This dermatomal loss can be explained by meralgia paraesthetica

24

What is the definition and management of meralgia paraesthetica?

Compression of lateral femoral cutaneous nerve (L2, L3)
Tx: Reassure, avoid tight garments, lose weight. If persistent, carbamazepine, gabapentin

25

Which nerve supplies the sensory innervation to the lateral 3 fingers (thumb, index finger and middle finger)?

Median nerve

26

Which nerve supplies the pinky finger and half of 4th finger?

Ulnar nerve

27

Which nerve supplies the back of the thumb?

Radial nerve

28

What is the definition of radiculopathy?

Disease of nerve roots

29

What are the causes of radiculopathy?

Compression by:
1. Disc herniation
2. Spinal canal stenosis (degenerative changes) e.g. lumbosacral radiculopathy

30

What is sciatica?

Pain in buttock, radiating down to leg below the knee