Multiple Sclerosis Flashcards
What is MS?
inflammatory demyelinating disease of the CNS
List 4 types of MS
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
What causes MS?
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
List 2 risk factors for MS
EBV exposure
Prenatal vitamin D
What do symptoms depend on in MS?
Site of inflammation
Describe the epidemiology of MS
F > M
Age of onset: 20-40 yrs
Optic neuritis is the most common presentation of MS, what does this involve?
Unilateral deterioration of visual acuity + colour perception
Pain on eye movement
Common 1st sx
What are 3 sensory symptoms of MS?
Pins + needles
Numbness
Burning
What signs indicate optic neuritis on examination in MS?
Impaired visual acuity (MOST COMMON)
Loss of coloured vision
Fundoscopy: swollen optic nerve head in active disease, optic atrophy in chronic
What 6 general signs are seen on examination in MS?
Sensory: Paraesthesia Motor: UMN signs Cerebellar: Limb ataxia (intention tremor, past-pointing, dysmetria) Dysdiadochokinesia Ataxic wide-based gait Scanning speech
What is diagnosis based on in MS?
Finding 2 or more CNS lesions with corresponding symptoms, separated in time + space (McDONALD CRITERIA)
List 3 investigations performed for MS
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
What are 4 motor symptoms of MS?
Limb weakness
Spasms
Stiffness
Heaviness
What are 4 autonomic symptoms of MS?
Urinary urgency
Hesitancy
Incontinence
Impotence
What are 2 psychological symptoms of MS?
Depression
Psychosis
What is Uhthoff’s phenomenon?
transient increase/ recurrence of sx due to conduction block precipitated by rise in body temperature
What is Lhermitte’s phenomenon?
Electrical sensation that runs down back + into the limbs when the neck is flexed
Which form of MS is most common?
Relapsing remitting
What may be found on visual fielding testing in MS?
Central scotoma (if optic nerve is affected) Scotoma = a blind spot in the normal visual field Field defects (if optic radiations are affected)
What 2 other defects may be found on examination of the eye in MS?
Relative Afferent Pupillary Defect
Internuclear Ophthalmoplegia
What occurs in internuclear ophthalmoplegia?
Lateral horizontal gaze causes failure of adduction of the contralateral eye
Indicates lesion of contralateral medial longitudinal fasciculus
