Parkinson's Flashcards
Characteristics of Parkinson’s syndrome
-Bradykinesia
-Rigidity
-Tremor
-Postural instability
Underlying structure targeted in Parkinsonism
-Extrapyramidal
=basal ganglia
=certain brain stem nuclei
=Connections
What does the Extrapyramidal system do?
-Modifying and organising movements
=Encouraging wanted movements
=Inhibiting unwanted movements
=Organising individual movements into actions
-Sequenced learned voluntary acts
-Semi-automatic movements
-Emotional movements
Describe bradykinesia
-Primary cause of motor disability
-Slowness and difficulty in performing actions
=Initiating, stopping, executing
-Actions formed of sequenced patterns
=walking, writing
-Individual movements= power unaffected
Where is bradykinesia especially seen in?
-Learned, sequenced actions that are done automatically (walking)
-Automatic things like blinking, swallowing saliva, fidgeting
-Emotional/ communicative actions (non-verbal gestures, facial expressions)
Describe rigidity in Parkinson’s
-Increased in tone
-Different in spasticity in UMN pyramidal disease
Describe tremor in Parkinson’s
-Not necessary for Parkinsonism
-Most obvious feature
=Present at rest
=3-5 Hz
=Worse when stressed or tired
=Improves with voluntary movement
=Pill-rolling
Actual causes of Parkinson’s
-Drug-induced
-Idiopathic disease
-Other primary degenerative diseases
-Miscellaneous
Drug causes of Parkinson’s
-Chlorpromazine (anti-psychotic) in young
-Prochlorperazine (anti-nausea) in old
Describe idiopathic Parkinson’s disease
-Lewy bodies
-Substantia nigra neuronal death
-Related loss of neuromelanin
-Deposition of abnormal folded protein- alpha-synuclein
-Nigro-striatal dopaminergic deficit
-Neurogenerative disease
Clinical signs of idiopathic Parkinson’s disease for diagnosis
-Insidious onset
-Gradually progressive
-Parkinsonian features
=Postural instability not an early feature
-Typically unilateral onset
-No other features (pure= cerebellar ataxia, pyramidal weakness)
Investigations for IPD
-Arguably none in typical cases
-CT/MR imaging not routinely necessary = SPECT
-DAT-Scan may be helpful when uncertain
-Dopaminergic agent trial
Types of treatment for Parkinson’s
-Prophylactic
-Symptomatic
-Disease-modifying
IPD treatment (symptomatic)
-Levodopa (motor symptoms)
-Dopamine agonist
-Monoamine oxidase B
-COMT inhibitor
-DDA (Direct Dopamine Agonists)= Ropinorole
-LDOPA (Madopar, Sinemet) (dopamine precursor)
-Selegeline (monoamine oxidase inhibitor)
-Amantadine
-Anticholinergic drugs
Why are there emerging problems in IPD treatment longer term?
-Progressive disease (treatment is symptomatic)
-Drug toxicity
-CNS plasticity- changes in neuronal transmission
=Reduced efficacy
=Shorter durations of response
=Fluctuations in disability
=Unpredictable and variable response- emergence of involuntary movements (chorea, Athetosis, dystonia/ confusion, hallucinations, dementia)
