Specific Diseases of CNS

Question 1

Multiple Sclerosis

Answer 1

Inflammatory, autoimmune disease involving demylination of oligodendrites and neurones in the CNS creating plaques. Mediated by T cells. Cell loss, gliosis and demyelination.

Question 2

Types of multiple sclerosis

Answer 2

Relapsing-remitting - periods of exaceration then recovery.
Secondary progressive - initial RRMS but disease progresses to no remission periods.
Primary progressive - Never any remission, constant deterioration.

Question 3

Pathophysiology of MS

Answer 3

T cell mediated demylination. Poor recovery leads to neuronal loss, scarring (plaques).

Question 4

Risk factors for MS

Answer 4

Genetic
Epstein-barr virus (trigger?)
Female
Smoking
Low vit D
Adolescent obestity

Question 5

Complications of MS

Answer 5

Fatigue
Spasicity (stiffness + muscle spasm)
Ataxia
Incontinence
Sexual dysfunction
Tremor
Visual impairments (optic neuritis, diplopia)
Pain
Poor mobility
Poor mental health

Question 6

Differential diagnosis of MS presentation

Answer 6

Neuromyelitis optica (worse mortality than MS)
SLE
Sarcoidosis
Lyme disease
Vitamin B12 deficiency
Behcet’s syndrome (+oral and genital ulcers, and uveitis)
Neurosyphilis

Question 7

Uhthoff’s phenomenon

Answer 7

Heat and exercise potentiate ON/MS symptoms (with hot food or in a hot bath vision can decrease)

Question 8

Optic neuritis symptoms

Answer 8

Partial or total unilateral visual loss
Pain behind the eye, particularly on eye movement
Decrease in acuity of eyesight.
‘Washed-out’ colours
Rarely Argyle Robertson type pupil (lesion near edinger-westphal nucleus)

Question 9

S+S of MS

Answer 9

Females between 20 and 30 years
Symmetrical or asymmetrical possible.

Symptoms:
Optic neuritis
Paraesthesia
Weird walking
Urinary urgency/frequency/retention
Constipation
Swallowing problems

Signs:
Weakness
Lhermitte’s sign -neck flexion causes shocking pain through trunk.
Brainstem/Cerebellar - ataxia, diplopia, dysarthria, dysphagia

Question 10

Diagnosis and investigations for MS

Answer 10

Ix = FBC, CRP/ESR, LFT, renal function, HbA1c, TFT, Vit B12, calcium. LP for CSF electrophoresis, CNS MRI, evoked potential test.

MacDonald’s Criteria.

• 2 episodes of a relapse disseminated in time and space lasting greater than 1hr. MRI scan lesion evidence.
• Delayed evoked potentials
• Lumbar puncture CNS has oligocloncal bands of IgG in CSF on electrophoresis.

Question 11

Treatment of an acute relapse

Answer 11

Methylprednisolone to shorten duration.

Question 12

Long-term treatment and management of MS

Answer 12

Interferons 1beta and 1alpha or monoclonal antibodies (Alemtuzumab) to reduce relapse occurrence.
Manage complications e.g. Baclofen for spasticity, self-catheterisation.
Stress-free life
Stop smoking
Regular exercise
Sign post to information to patient and carer.

Question 13

Ramsay Hunt Syndrome

Answer 13

Varicella zoster virus/Herpes simplex 3 reactivated in geniculate ganglion of 7th cranial nerve (facial).
Auricular pain is often the first feature
Ipsilateral facial nerve palsy, forehead NOT spared.
Vesicular rash around the ear/pinna
Vertigo and tinnitus
RX = prednisolone + acyclovir.

Question 14

Carotid artery stenosis

Answer 14

Bruit
Carotid Doppler
Cause anterior circulation stroke
Treat with carotid endarterectomy

Question 15

Horner’s syndrome

Answer 15

Constricted pupil (miosis), drooping of the upper eyelid (ptosis), absence of sweating of the face (anhidrosis).
Caused by lateral medullary syndrome (from a stroke in posterior inferior cerebral artery), Pancoast tumour in chest, carotid artery dissection.

Question 16

Pathogenesis of Parkinson’s disease

Answer 16

Chronic, progressive neurodegeneration of dopamine-containing cells in the substantia nigra in basal ganglia. Parkinson’s disease becomes apparent at 50% loss neurones.
Lewy bodies present in remaining neurons.
Effects nigro-striatal pathway signalling.

Question 17

Cause of Parkinson’s

Answer 17

Genetic predisposition and environmental factors.

Question 18

Motor clinical features of Parkinson’s disease

Answer 18

Tremor - pill-rolling
Rigidity - cog-wheel in combo with tremor or lead-pipe
Bradykinesia - reduced blinking, swallowing difficulty, difficulty in initiating movements (start hesitation), micrographic handwriting, mask-like expression, drooling, stiff shuffling gait, reduced asymmetrical arm swing, stooped posture, freeze on turning.

Question 19

Non motor features of Parkinson’s

Answer 19

Constipation
Urinary difficulties
Depression
Dementia
Pressure sores

Question 20

Management of Parkinson’s

Answer 20

MDT
NICE recommends not to start drug until diagnosis confirmed by a specialist.
Vit D supplements
NOTIFY DVLA

L-dopa  + dopa-decarboxylase inhibitor.
Dopamine agonist (Ropinirole)
oral monoamine oxidase B inhibitor

Question 21

L-dopa

Answer 21

+ dopa-decarboxylase inhibitor to prevent peripheral dopamine decarboxylation. Co-carelopa.
Improve motor symptoms but so much tremor and non-motor symptoms.
Efficacy reduces with time (end-of-dose) but up the dose, increase SE. Also get on and off periods of effect.
SE = IMPULSIVITY!! visual hallucinations, drowsy, painful dystonia, nausea and vomiting.

Question 22

Oral monamine oxidase B inhibitors

Answer 22

Selegiline.
Early PD
SE = postural hypotension, AF.

Question 23

oral dopamine agonists

Answer 23

Ropinirole
Delay use of L-dopa so efficacious for longer.
Less effective at improving motor symptoms.
Can get transdermal patches.

Question 24

Causes of parkinsonism

Answer 24

Lewy body dementia
Wilson's disease
HIV
Repeated head injury (boxers)
Huntington's disease
First generation antipsychotics
Antiemetics

Question 25

Myasthenia Gravis pathophysiology

Answer 25

Autoimmune disease where B cells and T cells target the nicotinic acetylcholine receptor reducing the number of working post-synaptic Ach receptors.

Question 26

Epidemiology of Myasthenia Gravis and its associated disease

Answer 26

Women aged 20-35, more likely to have thymus hyperplasia. | Older men over 60 who are more likely to have thymus atrophy to thymoma tumour.

Question 27

Differential diagnosis of dysphasia

Answer 27

``` Stroke. Bulbar palsy Pseudobulbar palsy Myasthenia Gravis Oesophageal cancer ```

Question 28

Clinical features of myasthenia gravis

Answer 28

Fatiguability on repeated use of muscles. Speech and swallow bulbar symptoms common in elderly. Ocular - ptosis, diplopia Cranial Nerve - Dysarthria, dysphasia, dysphagia, face and jaw weakness. Causes poor chewing, jaw open when chewing, head drop. Muscle groups affected - face, trunk, limbs. Difficulty getting out of chair, SOB when lying down. Normal reflexes but fatigue on repeated testing.

Question 29

Exacerbating factors for symptoms of myasthenia gravis

Answer 29

Beta-blockers, quinine, opiates, exercise, infection, hypokalaemia, pregnancy, change in climate.

Question 30

Investigations for myasthenia gravis

Answer 30

Tensilon test. Serum anti-acetylcholine receptor antibodies, serum anti-muscle-specific kinase antibodies. Thyroid CT and thyroid function test. Neurophysiology testing - repetitive nerve stimulation gives decreases response.

Question 31

Management of myasthenia gravis

Answer 31

Pyridostigmine - anti-cholinesterase helps control symptoms. 2nd line = prednisolone to help relapses and control symptoms. Give bone density protection. Consider thymectomy. Ensure no medications are potentiating the disease.

Question 32

Complications of myasthenia gravis

Answer 32

1) Myasthenia crisis - weakness of respiratory muscles. Life-threatening emergency!!!!!! Immunoglobulins (IV Ig), plasmapheresis and steroids (prednisolone). 2) Cholinergic crisis - too much medication. Muscle fasciculation, pallor, sweating, hypersalivation and small pupils, bradycardia. Rapidly decrease meds.

Question 33

Lambert-Eaton myasthenia syndrome

Answer 33

Occurs as autoimmune disease target presynaptic calcium channels or in paraneoplastic small cell lung cancer. No acetylcholine release. Weak proximal muscles = unsteady gait. Autonomic symptoms (constipation, dry mouth). Weakness improves on exercise. Hyporeflexia.

Question 34

Bell's palsy and treatment

Answer 34

Acute, unilateral facial nerve paralysis where the cause is unknown (diagnosis of exclusion). ∆∆ for CN7 palsy but in Bell's pt can not raise their eye brows as not forehead sparing. Rx = Prednisolone within 72hrs of onset, lubricate eyes with drops,

Question 35

Causes of facial nerve/CN7 palsy

Answer 35

``` Ramsay-Hunt syndrome + HSV3. Lyme disease Meningitis Stroke Tumour Multiple sclerosis Gullian-barre syndrome Parotid gland tumours ```

Question 36

Symptoms of facial nerve/CN7 palsy

Answer 36

``` Facial weakness - Unilateral sagging of mouth, saliva drooling, speech difficulty. Numbness or pain around ear. Decrease taste Hypersensitivity to sounds Forehead sparing - can raise eye browns ```

Question 37

Bulbar palsy

Answer 37

Impairment in nuclei of cranial nerves 9-12 in medulla. Gives lower motor neuron signs in the tongue. Tongue fasciculation, flaccid tongue, quiet, nasal or hoarse voice. Caused by Guillian-barre syndrome, myasthenia gravis, motor neurone disease, brainstem tumour, polio.

Question 38

Pseudobulbar palsy

Answer 38

UMN signs due to UMN lesion in muscles of mastication and talking. Slow tongue movements, increase jaw jerk, increase palatal reflex, mood incongruent crying.

Question 39

Example of mononeuropathy and polyneuropathy

Answer 39

``` Mononeuropathy = Carpal tunnel syndrome (median nerve compression) Polyneuropathy = Guillian-Barre syndrome (demyelinating polyradiculoneuropathy) ```

Question 40

Carpel tunnel syndrome associated diseases, clinical features, investigations and management.

Answer 40

MEDIAN NERVE COMPRESSION Associated disease = hypothyroidism, DM, pregnancy, acromegaly, rheumatoid arthritis. Presentation = Tingling, pain and numbness in lateral 3+1/2 fingers (thumb, index finger, middle finger, and radial half of the ring finger) and palm, can extend up arm. Wakes patient at night. Weakness in thenar muscles. Relieved on shaking arm. Tinnel's test (tap on nerve/wrist) & Phalen's test (flex wrist). Ix = nerve conduction studies. Rx = splints, corticosteroid injections, decompression surgery.

Question 41

Guillian-Barre syndrome pathogenesis

Answer 41

Post-infection inflammatory, demyelination and axonal loss polyneuropathy. Commonly post URTI or gastroenteritis of viral cause.

Question 42

Clinical features of Guillian barre syndrome

Answer 42

SYMMETRICAL, occuring less than 6 weeks after infection Ascending weakness and paraesthesia starting in lower limbs Areflexia of lower limbs Neuropathic pain in BACK and legs. Autonomic dysfunction = sweating, tachycardia, hypertension. Sensory changes may not occur. Facial weakness = dysarthria and dysphasia. Death via respiratory muscle weakness. Apyrexial at presentation.

Question 43

Investigations for gullian barre syndrome

Answer 43

``` Nerve conduction studies = EMG, slow conduction due to demylination. Lumbar puncture = high protein in CSF. Spirometry and FVC. Antiganglioside autoantidbody, LFT ```

Question 44

Treatment of Guillian barre syndrome

Answer 44

IV immunoglobulins. Plasma exchange. Good prognosis for recovery but may have incomplete with relapsing and remitting disease.

Question 45

Sciatica

Answer 45

Compression of lumboscaral nerve roots emerging from spinal canal. Most commonly due to herniated intervertebral disc. Pain, tingling, and numbness felt in the distribution of the nerve root (dermatome). May be accompanying motor weakness in a corresponding myotomal distribution.

Question 46

Cauda equina syndrome red flags

Answer 46

Severe lower back pain. Weakness, sensory loss and pain commonly bilaterally. Difficulty in micturition or incontinence. Saddle paraesthesia Loss of sensation of rectal fullness (faecal incontinence) Laxity in anal sphincter Areflexia of lower limbs. MRI MRI MRI MRI and urgent neurosurgery.

Question 47

Dementia, apraxia, urinary incontinence + history of subarachnoid haemorrhage =

Answer 47

normal pressure hydrocephalus

Question 48

Signs of demyelination or axonal damage on electromyography

Answer 48

``` Demyelination (in conditions such as MS and GBS) = increased latency, decrease velocity, conduction block. Axonal damage (in conditions such as VitB12 def and alcohol) = lower amplitude with no change in velocity. ```

Question 49

Difference between Electroencephalogram and electromyography

Answer 49

``` EEG = CNS activity recorder. EMG = peripheral nerve function from anterior horn and below. ```

Question 50

CV causes of dizziness

Answer 50

Postural HTN, dehydration, haemorrhage, tachycardia, arrthymia, anaemia, vasodilation = anxiety, pain, shock (carbamazepine OD, infective shock)

Question 51

Mononeuritis multiplex

Answer 51

2 or more peripheral nerves affected by a neuropathy. Subacute presentation. Causes are often systemic: Rheumatoid, DM, Sarcoidosis, leprosy, AIDS

Question 52

Tensilon test

Answer 52

Inject edrophonium = transient improvement in muscle function Can be used to test for a myasthenic crisis from a cholinergic crisis.

Question 53

Features of a third nerve palsy

Answer 53

Eye is deviated 'down and out' Ptosis Dilated pupil, if not dilated think PICA stroke! Eye affected = same side as lesion

Question 54

Ataxic gait

Answer 54

Cerebellar disease Wide based Loss of heel-toe pattern increased foot rotation angles.

Question 55

Motor neuron disease pathophys

Answer 55

Loss of neurones in the motor cortex, cranial nerve nuclei and anterior horn cells. Leads to upper and lower motor neuron signs but no sensory loss, eye movement pathology or sphincter disturbance.

Question 56

4 clinical patterns of motor neuron disease

Answer 56

Amyotrophic lateral sclerosis Progressive bulbar palsy Progressive muscular atrophy Primary lateral sclerosis.

Question 57

Amyotrophic lateral sclerosis.

Answer 57

``` Ax = Most common MND. Degeneration of neurones in motor cortex and anterior horn cells. CFx = LMN and UMN signs. Stumbling, spastic gait. Foot drop. Weak grip, can't open jars. Aspiration pneumonia. Dx = El Escorial diagnostic criteria of LMN and UMN signs + EMG results. Exclude other causes with MRI, LP. Rx = MDT, Riluzole can help with spasticity, BiPAP, supportive and palliative care, carer support. ```

Question 58

UMN signs

Answer 58

``` Upgoing plantars/positive Babinski sign. Muscle weakness Spasticity Hyperreflexia +/- clonus No muscle wasting Hypertonia ```

Question 59

LMN signs

Answer 59

``` Muscle wasting Fasciculations Hypotonia Hyporeflexia Flaccidity ```

Question 60

Split hand sign

Answer 60

Seen in ALS | Excessive wasting of muscles around the thumb

Question 61

Factors which make ALS diagnosis worse

Answer 61

Older Bulbar area onset symptoms Low FVC

Question 62

Diagnosis of amyotrophic lateral sclerosis

Answer 62

El Escorial Criteria

Question 63

El Escorial criteria definite ASL

Answer 63

LMN and UMN signs in 3 regions

Question 64

Sudden withdrawal of L-dopa

Answer 64

Neuroleptic malignant syndrome.

Question 65

Sciatic nerve

Answer 65

Roots of L4-S3. | 2 branches = tibial and common fibular nerve.

Question 66

Causes of caudal equina

Answer 66

``` Spinal trauma Spinal infection or epidural abscess Birth abnormalities e.g. spina bifida Tumour - boney mets, lymphomas. Post lumbar spine operation haematoma ```

Question 67

What disease is associated with giant cell arthritis and what would the patient complain of

Answer 67

Polymyalgia rheumatica. Female patients! GCA = granulomatous vasculitis, jaw claudication diplopia, headache. PMR = pain and morning stiffness of neck, shoulder, pelvis. Difficulty rising from seat, joint pain, muscle tenderness.

Question 68

Inheritance of Huntington's disease

Answer 68

Autosomal dominant | Increase in CAG triplet repeats on Huntingtin gene Chr4.

Question 69

What is anticipation in relation to Huntington's disease?

Answer 69

Greater number of CAG repeats. Earlier age of presentation. Increased severity of the disease.

Question 70

Presentation of Huntington's disease

Answer 70

- Start to present around 30-50yrs. - Psychotic and behavioural abnormalities, self-neglect, apathy. - Clumsiness and fidgeting and eventually chorea. - Parkinsonism and dystonia - Eye movement disorders, dysphagia, dysarthria. - Dementia and cognitive impairment.

Question 71

Ix and Rx for Huntington's

Answer 71

Ix: Head CT (caudate atrophy), Genetic testing. Rx: MDT, psychological support for pt and family, SALT, Benzos for chorea, levodopa for Parkinsonism, advice on advanced directive/legal power of attorney.

Question 72

Area of brain affected by Huntington's

Answer 72

Putamen and caudate nucleus (aka the striatum)

Question 73

Whats the Gower test for

Answer 73

Muscular dystrophy. +ve indicated proximal muscle weakness. Children crawls up using hands to get up from squatting position.

Question 74

Cause of a fixed dilated pupil

Answer 74

CN3 palsy, damage to the parasympathetic fibres so can't constrict pupil.

Question 75

What signs pint towards a Parkinson's plus syndrome rather than PD?

Answer 75

Early falls Early cognitive decline Early bladder and bowel dysfunction Both sides affected equally (in PD, normally one side is worse)

Question 76

Dysarthria and dysphagia definitions and differences

Answer 76

Dysarthria is a disorder of speech and articulation. Poor bulbar muscles. Disease of cerebellum. Dysphasia is a disorder of language. Can be receptive (unable to comprehend but give fluent answers, WERNICKE'S AREA) or expressive (unable to respond, random sounds, Broca's area).

Question 77

How to differentiate receptive and expressive dysphasia

Answer 77

Ask to follow command. | Receptive cant but expressive can.

Question 78

Investigation for neuro causes of breathing difficulty

Answer 78

Monitor FVC

Question 79

Medical Mx of a brain tumour and side effect

Answer 79

Dexamethasone, insomnia.