Multiple Sclerosis

Question 1

What is MS?

Answer 1

inflammatory demyelinating disease of the CNS

Question 2

List 4 types of MS

Answer 2

Relapsing-Remitting: attacks of demyelination with almost complete recovery between attacks

Clinically Isolated Syndrome:
Single clinical attack of demyelination (does NOT count as MS)
10-50% progress to develop MS

Primary Progressive:
Progressive accumulation of disability from onset

Secondary Progressive:
progressive accumulation of disability after initial relapsing course

Question 3

What causes MS?

Answer 3

UNKNOWN
AI basis with potential environmental trigger in genetically susceptible individuals
Immune-mediated damage to myelin sheaths results in impaired axonal conduction. Associated grey matter atrophy

Question 4

List 2 risk factors for MS

Answer 4

EBV exposure

Prenatal vitamin D

Question 5

What do symptoms depend on in MS?

Answer 5

Site of inflammation

Question 6

Describe the epidemiology of MS

Answer 6

F > M

Age of onset: 20-40 yrs

Question 7

Optic neuritis is the most common presentation of MS, what does this involve?

Answer 7

Unilateral deterioration of visual acuity + colour perception
Pain on eye movement
Common 1st sx

Question 8

What are 3 sensory symptoms of MS?

Answer 8

Pins + needles
Numbness
Burning

Question 9

What signs indicate optic neuritis on examination in MS?

Answer 9

Impaired visual acuity (MOST COMMON)
Loss of coloured vision
Fundoscopy: swollen optic nerve head in active disease, optic atrophy in chronic

Question 10

What 6 general signs are seen on examination in MS?

Answer 10

Sensory: Paraesthesia  
Motor: UMN signs  
Cerebellar: Limb ataxia (intention tremor, past-pointing, dysmetria) 
Dysdiadochokinesia 
Ataxic wide-based gait  
Scanning speech

Question 11

What is diagnosis based on in MS?

Answer 11

Finding 2 or more CNS lesions with corresponding symptoms, separated in time + space (McDONALD CRITERIA)

Question 12

List 3 investigations performed for MS

Answer 12

LP: Microscopy- exclude infection/ inflammatory causes
CSF electrophoresis shows unmatched oligoclonal bands
MRI Brain, Cervical + Thoracic spine (with gadolinium)
Plaques detected as high signal lesions.
Gadolinium enhancement shows active lesions
Evoked Potentials:
Visual, auditory + somatosensory evoked potentials may show delayed conduction velocity

Question 13

What are 4 motor symptoms of MS?

Answer 13

Limb weakness
Spasms
Stiffness
Heaviness

Question 14

What are 4 autonomic symptoms of MS?

Answer 14

Urinary urgency
Hesitancy
Incontinence
Impotence

Question 15

What are 2 psychological symptoms of MS?

Answer 15

Depression

Psychosis

Question 16

What is Uhthoff’s phenomenon?

Answer 16

transient increase/ recurrence of sx due to conduction block precipitated by rise in body temperature

Question 17

What is Lhermitte’s phenomenon?

Answer 17

Electrical sensation that runs down back + into the limbs when the neck is flexed

Question 18

Which form of MS is most common?

Answer 18

Relapsing remitting

Question 19

What may be found on visual fielding testing in MS?

Answer 19

Central scotoma (if optic nerve is affected) 
Scotoma = a blind spot in the normal visual field 
Field defects (if optic radiations are affected)

Question 20

What 2 other defects may be found on examination of the eye in MS?

Answer 20

Relative Afferent Pupillary Defect

Internuclear Ophthalmoplegia

Question 21

What occurs in internuclear ophthalmoplegia?

Answer 21

Lateral horizontal gaze causes failure of adduction of the contralateral eye
Indicates lesion of contralateral medial longitudinal fasciculus