Extrapyramidal Flashcards
What is the role of the basal ganglia?
It unconsciously helps you correctly pattern organized movements and inhibits unwanted movement (the more you practice a movement, the less cortical involvement and the more subcortical involvement)
What is the pathology of Parkinson’s?
The Substantia Nigra pigmented neurons die off and the DOPA producing capacity is reduced (symptoms develop when DOPA production is down to 20-30% of normal)
Hyperkinesias
extra movements (chorea, athetosis, dystonia, ballismus, tics, tremors)
Hypokinesias
muted or inhibited forms of movement (bradykinesia, slowed postural reactions, mask facies, rigidity, freezing)
dystonia
abnormal sustained, repetitive muscle contractions resulting in twisting motions and unsual postures
Huntington’s Disease
Autosomal dominant trinucleatide repeat (CAG >40) disease with a mean onset of 35-40 yrs that presents with CHOREA, ATHETOSIS, DEMENTIA, BEHAVIORAL CHANGES. Course is generally 13 years of progressive decline. NO effective tx, just symptomatic help. High suicide rate.
Essential Tremor
A postural and intentional type, symmetrical tremor that can be sporadic or genetic. Tends to come on in early adulthood and worsen with age, though alcohol can suppress it.
Essential Tremor vs Parkinson’s Tremor
Essential: postural/action, often familial, bilateral, symmetric, slowly propressing, hands, head & voice involvement
Parkinson’s: static/resting, usually sporadic, typically presents unilaterally, may progress rapidly, hand & leg involvement
Parkinsonism
Condition of having 2 of 3 classic Parkinson findings (bradykinesia, rigidity, tremor) of insidious onset that start unilateral and progress to bilateral that may be cuased by something other than Parkinson’s (drug interactions (MPTP)…etc)
Parkinson’s Disease
Mostly sporadic disease characterized by bradykinesia, rigidity, and resting tremor that is caused by the depigmentation of the substantia nigra. Mean survival is 15 yrs. Can be with or without Lewy Body inclusions (synuclein aggregates in CNS).
Parkinson’s Plus Diseases
Whole list of syndromes that present like Parkinson’s but with other symptoms also - clues that it is not Parkinson’s include: no tremor, poor response to DOPA, early dementia, frequent falls at time of diagnosis.
Parkinson’s Treatment
Replace the dopamine - levodopa and carbidopa Surgical tx (abalation - thalamotomy, pallidotomy, DBS...)
Alzheimer’s Disease
Most prevalent dementing disease caused by diffuse atrophy of the brain. Most cases are sporadic - unless early onset. Pathology is characterized by neurofibrillary tangles and AB-amaloid plaques.
Genetic variants of Alzheimer’s Disease
- B amyloid protein mutation on chromo 21
- presenilin mutation
- APO E - isoform 4 leads to increased risk
- tau abnormalities
What is the problem secretase in Alzheimer’s?
gamma-secretase causes the breakdown of amyloid into insoluble forms
Frontotemporal Dementia
tauopathy that causes behavioral issues, progressive non-fluent aphasia and/or semantic dementia. It leaves perceptual skills and non-verbal problem solving and short term memory intact. It can be caused by Pick’s disease, Chromo 17 (tau protein) abnormalities, Parkinsons/Lewy Body Dementia, or Progressive Supranuclear Palsy.
Pick’s Disease
Degeneration of the frontal and anterotemporal lobes due to abnormal tau protein agglutination and the formation of pick bodies in neuronal cell bodies.
Progressive Supranuclear Palsy
Cause of frontotemporal dementia that is characterized by globose (round) tangles in the brainstem and thalamus.
What types of dementia do Parkinson’s patients experience if they are part of the 50% who get dementia?
25% - Alzheimers
25% - Lewy Body Dementia
What are examples of TDP43-opathies?
ALS familial type (rare), frontotemoporal dementia with ubiquinated inclusions, and some other genetic diseases
What are examples of Trinucleotide Repeat Diseases?
- Huntington’s
- Spinocerebellar ataxia
- Friedreich’s ataxia
Friedreich’s ataxia
GAA trinucleotide repeat disorder that presents in children with ataxia, hyporeflexia, and + Babinski. Progresses to death in mid 20s usually due to cardiac issues.
What percentage of people with Parksinson’s will have a tremor?
2/3 or 66%
Tourette’s Syndrome
Polygenetic, hereditary syndrome that presents between the ages of 2-15 with Tics that may resolve by 18 years of age (50%) or atleast usually decrease overtime. Can have vocal and/or motor tics.
