Lecture 7 - Demyelination Ataxia Flashcards
What is ADEM (Acute disseminated encephalomyelitis)
Acute demyelinating illness that commonly follows an infection or vaccine (75%)
rare
MRI shows BILATERAL symmetric inflammation of the same age (meaning it started at the same time)
How does ADEM usually progress
usually monophasic, but can reoccur
ADEM is most common in what patients
Children
how does ADEM look on an MRI?
big fluffy areas of inflammation on both sides
What does “sensory level noted at T4” mean?
Sensory issues below T4
What is Acute Transverse Myelitis?
Inflammation of spinal cord causing lesions
Can be first episode of multiple sclerosis (MS), espeicially if brain MRI is also abnromal
How will acute Transverse myelitis appear on an MRI?
Small patchy lesions limited to two areas different vertebral segments
How will Acute Transverse myelitis present
Back pain, sensory level problems at spine (example: everything under T4 doesnt work), sphincter disturbances (bowel and bladder), paraparesis
How will optic neuritis present?
Pain w/ eye movement
pale and inflamed optic disc
vision loss, loss of color vision
Consensual pupillary constriction no longer works when shining light into that eye, nor does the right eye dilate when you shine light into the right eye itself
however, the L can consensually constrict the R eye still
Optic neuritis is a common initial symptom of ________________
MS
w/ abnormal brain MRI, 56% had MS in 10 years
w/ normal brain MRI, 22% had MS in 10 years
What factors increase the risk for MS?
Younger age, female, previous neuro symptoms, multiple MRI lesions
What is the normal treatment for optic neuritis?
IV steroids
Optic neuritis on its own is usually ___________
monophasic
but not if its related to MS
How can Transverse Myelitis and Optic Neuritis be confirmed to be MS
Recurrent or other attacks elsewhere
What is MS (Multiple Sclerosis)
Immune mediated disease of CNS
leading cause of non-traumatic disability in young adults
Where is MS more common?
What is the peak onset age of MS?
What gender is more common?
How does it affect life expectancy?
North of equator, greater rates w/ greater distance
20-30
female
reduces by 7-14 years
What are MS risk factors?
Note: exact cause of MS is not known
Risk factors: EBV exposure (Epstein-Barr virus)
Low sun exposure
Obesity
Smoking
Genetic risk factor (20% heritability risk increase)
How does the demyelination happen in MS?
movement of auto-reactive T cells and demyelinating antibodies from the systemic circulation into the CNS through disruption of blood brain barrier
How does MS usually progress?
Recurrent attacks with partial recovery, each time you acquire more and more disability
(called RRMS) Relapsing Remittent Multiple Sclerosis
Note: disability can also trend up in straight line (primary progressive MS)
After 10 years what MS progression is more common?
Secondary Progressive Multiple Sclerosis
Basically it commonly starts as Relapse/remittent MS followed by a steady decline after a while (no more recover)
What happens to brain volume due to MS?
Decreases
Who has a better prognosis for MS?
Who has worse?
Better: Women, Caucasians, Monofocal onset, low relapse rate, low disablity at 5 years
Worse: Men, Non-white populations, Smoking/obesity, high relapse rate, high disability at 5 years
What bodily systems can MS effect
Every system
CNS, Visual,Speech, throat, MSK, sensation, bowel, urinary
What are the most common motor symptoms with MS?
What occurs later usually?
UMN spastic weakness 80%
spastic paraparesis is most common
Later: ataxia, tremor, incoordination, scanning speech
What are the most common sensory symptoms (what tract) experienced with MS?
75% of patients expeirence sensory issues
most common spinothalamic lesions, resulting in dysesthesias, pain
DCML involvement is less often
What is the sensory sensation that often happens with MS?
Lhermitte’s phenomenon
electric sensation passing down neck and limbs upon flexion of neck
What are common brainstem symptoms of MS?
Nystagmus, diplopia, facial weakness, vertigo, dysphasia and Trigeminal neuralgia
internuclear opthalmoplegia- due to lesion in medial longitudinal fasiculus- inability to adduct ipsilateral eye
note: trigeminal nerve effected because oligodendrocytes myelinate the first bit of the nerve in the CNS
What are the most common cognitive problems caused by MS?
Cognitive symptoms affect 60% of MS patients
usually have “subcortical dementia” which affects information processing, visuospatial, memory, and executive function
What kind of conditions make fatigue worse for MS patients?
Heat
Note: systemic fatigue very common
What is the most common diagnostic test for MS?
MRI of brainstem and spinal cord
CSF fluid tap to look for inflammatory changes
“evoked potentials” of visual, auditory, somatosensory
What does MS look like on a brain MRI?
diffuse inflammation and damage throughout
What do MS medications help with? What do they not help with?
Help with inflammation
but cannot fix nerves that are already damaged
When testing CSF in MS patients, what will you see?
WBC elevated
protein may be high
increased immunoglobulin production
(OCB)oligoclonal bands- presence of 2 or more antibody clons (indicates damaged blood brain barrier or immunoglobulin production in the brain)
What does the “Mcdonald criteria” for MS consists of
Includes:
- Prior attacks,
- new lesion on subsequent MRI,
- MRI with active or enhancing lesions and coexisting inactive lesions
- CSF oligoclonal banding
Evidence of atleast 2 areas damage at different times
The 2017 MS diagnostic criteria consists of what
2 different clincal attacks with 2 different locations at 2 different times
1 attack with MRI showing lesions, enhancing and non-enhancing (meaning one is progressing and one is old)
1 attack with MRI, and repeat MRI with new lesions 1 month later
What is the most common treatment of acute exacerbations of MS?
Steroids: IV or PO
or Plasma exchange
What is the difference between old vs new MS meds?
Older medications:
-very safe but not as effective , mainly injections
Newer medications
- more risk of infection but more effective
- by mouth (PO) or by monthly shot
What is Progressive Multifocal Leukoencephalopathy (PML)
Severe demyelinating disease of CNS due to JC virus infecting oligodendrocytes
note: 86% of the population have a asymptomatic infection of JC virus
the risk comes due to immunosupression associated with treatment of other autoimmune disorders (people with MS are at risk)
usually fatal within 1 year if not caught
can be treated by stopping immunosuppressants
will present like an MS attack at first
What are treatment goals associated w/ MS
Prevent longterm disability
no consensus on approach to therapy
If both optic discs are enlarged what is likely wrong?
If only one is enlarged?
Both: Increased intracranial pressure
one: Optic neuritis
_______ is common for patients with MS, especially in the lower extremities
Spasticity
MS patients also commonly have sexual dysfunction and spastic and flaccid bladder
what is the difference between spastic and flaccid bladder
Flaccid bladder - cant get urine out (leads to retention)
spastic bladder- overactive, frequency urgency
What medication works at the neuromuscular junction and is shown to increase walkingspeed in patients by an average of 25%
Ampyra (D-Alfampridine)
What is neuromyelitis optica (devic’s disease)
presents like transverse myelitis combined with bilateral optic neuritis
spinal cord transverse myelitis longitudinally extensive lesion across more than 3 vertebrae levels
more severe than MS
diagnosed through antibody testing NMO IgG
What is the treatment for acute NMO (neuromyelitis optica)
maintenance?
Acute attacks: Steroids, plasma exchange
Maintenance: medications
What is myelin oligodendrocyte glycoprotein antibody disease? (MOG)
Basically neuromyelitis optica (NMO) but for children and young adults (but all ages can be impacted)
Can be monophasic or relapsing
usually has optic neuritis, transverse myelinitis, and ADEM like CNS lesions
Has good recovery if treated like NMO
MOGAD vs AQP4+NMOSD
Basically these are both MOGAD
However, the regular MOGAD affects the lower spinal cord whereas the AQP4+ affects the upper spinal cord
How does ataxia present?
Disturbance in smooth preformance of voluntary motor acts
Error in rate, range, force, and duration
Quick overview of cerebellum:
Vermis is for:
Intermediate zone is for:
Lateral hemisphere is for:
Flocculonodular lobe is for:
Answer choices:
Proximal coordination
distal coordination
balance and vestiboccular reflex
motor planning for extremities
Vermis is for: Proximal coordination
Intermediate zone is for: distal coordination
Lateral hemisphere is for: motor planning for extremities
Flocculonodular lobe is for: balance and vestiboccular reflex
What are the clinical manifestations of cerebellar dysfunction
limb/trunk/gait ataxia
ipsilateral to lesions of the cerebellar hemisphere
impaired stance (wide)
intention tremor
Dysmetria
Dysdiadochokinesia
Impaired checking response
hypotonia
speech deficits: mutism, scanning, dysarthria
Nystagmus/abnormal saccades
What does scanning speech sound like?
uneven time and inflection points
no problem w/ word findng or speech production
Acute causes of ataxia
Intoxication
Vascuar lesions (strokes)
Trauma
Infections
Subacute causes of ataxia (days to weeks)
Brain tumors
Alcoholic-nutritional thiamine or vitamin E deficiency
Related to cancer (paraneoplastic)
Demyelinating cause (MS)
Causes of chronic ataxia (years)
Friedreich ataxia (common in kids)
Spinocerebellar ataxia (SCA)
Other cerebellar degeneration
Hereditary metabolic diseases
Rostral vermis syndrome is usually in what population?
What are the features?
Chronic alcoholics
features:
-wide base stance/gait
ataxia gait
impaired arm coordination
infrequent nystagmus/hypotonia,dysarthria
Caudal vermis syndrome is usually present in what population?
What are the features?
Typically in children w/ medulloblastoma
Features:
axial dysequilibrium and staggering gait
little to no limb ataxia
sometimes spontaneous nystagmus and rotated postures of head
cerbellar hemispheric syndrome is usually present in who?
What are the features?
People w/ infarcts, tumors, abscess
Features: incoordination of ipsilateral movements, particularly fine motor control
What are the causes of pancerebellar syndrome?
What are the features?
Causes: infection, hypoglycemia, hyperthermia, paraneoplastic, toxic-metabolic, hereditary
features: Bilateral cerebellar signs affecting limbs trunk and cranial musculature
What is the clincial presentation of friedreich ataxia?
Begins in childhood or young adulthood
loss of ambulation after 10-15 years
areflexia
foot deformities
scoliosis
cardiomyopahty
glucose intolerance
life expectancy: 40
usually presents w/ “proprioceptive gait w/ foot slap to increase sensation”
Why is it important to identify friedreich ataxia early?
is friedreich ataxia autosomal dominant or resessive?
what chromosome is affected?
New medication can slow progression by 50%
recessive
chromosome 9
