General Neurology

Question 1

What is an Arnold-Chiari malformation?

Answer 1

Downwards displacement, or herniation of the cerebellar tonsils through the foramen magnum.

Question 2

How can an Arnold-Chiari malformation be caused?

Answer 2

Congenital or Trauma

Question 3

What are the features of an Arnold-Chiari malformation?

Answer 3

Brainstem and lower cranial nerve dysfunction.

Non-communicating hydrocephalus - may develop as a result of obstruction of cerebrospinal fluid outflow.

Headache, difficulty swallowing, vomiting, dizziness, neck pain, unsteady gait, poor hand coordination, numbness and tingling to hands and feet, speech problems.

Syringomyelia - cyst forming in the spinal cord, can cause loss of sensation, paralysis and weakness in back, shoulders and extremities.

Question 4

How is an Arnold-Chiari malformation diagnosed?

Answer 4

MRI head

Question 5

How is an Arnold-Chiari malformation treated?

Answer 5

Decompressive surgery

Question 6

What type of lesion causes peripheral ataxia?

Answer 6

Cerebellar hemisphere lesions (Finger-nose ataxia)

Question 7

What type of lesion causes gait ataxia?

Answer 7

Cerebellar vermis lesions

Question 8

What is ataxia telangiectasia?

Answer 8

An autosomal recessive disorder caused by a defect in an ATM gene.

Question 9

What are the features of ataxia telangiectasia?

Answer 9

Typically presents in early childhood 1-5 years.

Abnormal movements (Cerebellar ataxia)
Telangiectasia (Spider angiomas)
IgA deficiency - recurrent infections
10% risk of malignancy

Question 10

What is autonomic dysreflexia?

Answer 10

Clinical syndrome occurring with spinal cord injury at or above T6 spinal level.

Afferent signals (from faecal impaction or urinary retention) cause an unopposed (due to lesion) sympathetic spinal reflex.

Unbalanced physiological response: Extreme hypertension, flushing, sweating (above lesion), agitation and potentially haemorrhagic stroke.

The management is removal of the stimulus and treatment of life-threatening hypertension or bradycardia.

Question 11

What is the cause of brown-sequard syndrome?

Answer 11

Caused by lateral hemisection of the spinal cord

Question 12

What are the features of brown-sequard syndrome?

Answer 12

Ipsilateral weakness below the lesion
Ipsilateral loss of proprioception and vibration sensation
Contralateral loss of pain and temperature sensation

Question 13

What is cataplexy?

Answer 13

Sudden and transient loss of muscular tone caused by strong emotion (e.g. laughter, being frightened)

Features include buckling knees to collapse

Question 14

What disease is associated with cataplexy?

Answer 14

Narcolepsy

Question 15

What space is filled by the CSF?

Answer 15

Space between the arachnoid mater and pia mater (covering surface of the brain)

Question 16

What is the approximate volume of circulating CSF?

Answer 16

150 ml

Question 17

Where is the CSF produced?

Answer 17

500 ml
Ependymal cells in the choroid plexus (70%)
Blood vessels (30%)

Question 18

Where is CSF reabsorbed?

Answer 18

Arachnoid granulation projecting into the venous sinuses

Question 19

What is the circulatory path of the CSF?

Answer 19

1. Lateral ventricles (via foramen of Munro)
2. 3rd ventricle
3. Cerebral aqueduct (aqueduct of Sylvius)
4. 4th ventricle (via foramina of Magendie and Luschka)
5. Subarachnoid space
6. Reabsorbed into the venous system via arachnoid granulations into the superior sagittal sinus.

Question 20

What is the composition of CSF?

Answer 20

Glucose: 50-80mg/dl
Protein: 15-40mg/dl
Red blood cells: Nil
White blood cells: 0-3 cells/mm^3

Question 21

What is Charcot-Marie-Tooth disease?

Answer 21

Most common hereditary peripheral neuropathy. Results in predominantly motor loss.

Question 22

What is the presentation of Charcot-Marie-Tooth disease?

Answer 22

Sprained ankles
Foot drop
High-arched feet
Hammer toes
Distal muscle weakness
Distal muscle atrophy
Hyporeflexia
Stork leg deformity

Question 23

What is the treatment of Charcot-Marie-Tooth disease?

Answer 23

Physical and occupational therapy.

Question 24

What is complex regional pain syndrome (CRPS)?

Answer 24

Neurological and related symptoms causing lasting pain, typically occurring following surgery or a minor injury.

Reflex sympathetic dystrophy (worse, long lasting pain) and causalgia (severe burning pain)

Women 3 > 1 Men

Question 25

What are the two types of CRPS?

Answer 25

Type 1 (most common): There is no demonstrable lesion to a major nerve
Type 2: there is a lesion to a major nerve

Question 26

What are the features of CRPS?

Answer 26

Progressive, disproportional symptoms to the original injury/surgery

Allodynia (pain from usually non-painful stimuli)

Temperature and skin colour changes

Oedema and swelling

Motor dysfunction

Question 27

What is used to diagnose CRPS?

Answer 27

Budapest Diagnostic Criteria

Question 28

What is the management of CRPS?

Answer 28

Early physiotherapy
Neuropathic analgesia
Specialist management

Question 29

What is electromyography (EMG) used for?

Answer 29

To evaluate the physiological properties of muscles at rest and whilst contracting

Question 30

What are the electromyography (EMG) characteristics of Neuropathic conditions?

Answer 30

Increased action potential duration

Increased action potential amplitude

Question 31

What are the electromyography (EMG) characteristics of Myopathic conditions?

Answer 31

Decreased action potential duration

Decreased action potential amplitude

Question 32

What specific characteristics are seen on electromyography (EMG) in Myasthenia gravis?

Answer 32

Diminished response to repetitive stimulation

Question 33

What specific characteristics are seen on electromyography (EMG) in Lambert-Eaton syndrome?

Answer 33

Incremental response to repetitive stimulation

Question 34

What specific characteristics are seen on electromyography (EMG) in Myotonic syndromes?

Answer 34

Extended series of repetitive discharges lasting up to 30 seconds