Parkinson's Flashcards
what is parkinsonism?
clinical syndrome that encompasses variety of diseases
what makes up the triad seen in parkinsonism?
Akinesia (brady/hypo)
Restign tremor
Rigidity
what is bradykineasia and hypokinesia?
bradykinesia = slowing of movements
hypokinesia = difficulty initiating movement
what kind of disorder is parkinsonism?
progressive neurodegenerative movement disorder
which tract is affected in parkinsons?
extra-pyramidal
which neurons are affected in parkinsons?
dopaminergic neurons are lost
which area of the brain is primarily affected in parkinsons?
pars compacta of the substantia nigrans
(causes disturbance in dopaminergic pathway)
how is a diagnosis of parkinsons made?
clinically- look at age, symtpoms
there is no diagnostic test
what is classically seen histologyically in parkinsons?
lewy bodies
(abnormal aggregates of protein)
what kind of onset is seen in parkinsons?
gradual onset
at what age will people typically develop parkinsons?
>55yrs
risk increases w age
what clinical features can be seen in parkinsons?
parkinsonism triad
shuffling gait
masked facies: loss of facial expressions
which later features concerning posture are seen in parkinsons?
flexed posture and postural instability
what are the non-motor symtpoms of parkinsons?
constipation
REM sleep behaviour disorder
depression
dementia
what drugs are used to manage parkinsons?
levodopa
monoamine oxidase B inhibitors
dopamine agonists
what is the MoA of levodopa?
dopamine precursor that crosses the BBB
what are the side effects of levodopa?
hypotension
nausea
dyskinesia
what is the MoA of Monoamine oxidase B inhibitors?
inhibits monoamine oxidase B: an enzyme reponsible for catabolising dopamine to homovanillic acid
what are the side effects of monoamine oxidase B inhibitors?
hypertensive crisis when consuming tyramine rich foods
what is the MoA of dopamine agonsits?
stimulate dopamine receptors directly
what aree the side effects of dopamine agonists?
hypotension
nausea
ankle swelling
hallucinations
who is likely to be prescribed dopamine agonists?
younger pateints (<70) due to high risk of dyskinesia in younger patients using levodopa
what is the one majot side effect seen when using levodopa?
‘overshoot’ from akinesia to dyskinesia
kwown as wearing off of the doses
what is drug induced parkinsonism?
onset of parkinsonian features after strarting or raising dose of some meds or after withdrawal of anti-parkinsonian agent
how soon is the onset of drug induced parkinsonism?
few weeks
how is drug induced parkinsonism treated?
cessation of causitive drug
what are some drugs that can cause drug induced parkinsonism?
chorpromazine
haloperidol
lithium
which has a lower risk of extrapyramidal symptoms, typical or atypical antipschotics?
atypical antipsychotics
if someoen on typical cannot stop their medication they will be switched to atypical instead
what can be used as an add in for symtpomatic relief in drug induced parkinsonism?
anticholinergics i.e. benztropine and procyclidine
dementia starting more than 1 year after onset of parkinsonism is called?
parkinsons disease dementia
dementia or cognitive symtpoms occuring before or at the same time as parkinsonism is termed?
Lewy Body Dementia
what are the three core features of lewy body dementia?
dementia
recurrent visual hallucinations
features of parkinsonism
what is multiple system atrophy?
parkinsonism along with autonomic dysfunction and/or cerebellar dysfunction
what autonomic features are seen in multiple system atrophy?
postural hypotension
erectile dysfunction
urinary urgency
what is seen on MRI in multiple system atrophy?
putaminal atrophy
‘hot cross bun’ appearance in pons in an axial section
putaminal atrophy on MRI is seen in what condition?
multiple system atrophy
‘hummingbird’ sign seen on MRI is classical of which condition?
progressive supranuclear palsy
what is seen in progressive supranuclear palsy?
axial akinesia and rigidity
loss of balance and unexplained falls, forgetfullness
loss of eye movements
what is the name for the loss of eye movements in progressive supranuclear palsy?
supranuclear gaze palsy
(especially on vertical plane)
atrophy of which area of the brain is seen in progressive supranuclear palsy?
midbrain atrophy
what is the cause of vascular parkinsonism?
mulitple small strokes or infarcts
people with vascular parkinsonism tend to have problems with gait or tremor?
gait
have more problems in lower body
does vascular parkinsonism progress more slowly or more rapidly in comparison to other types of parkinsonism?
progresses a lot slower
poor response to levodopa
what imaging is used to differentiate vascular dementia from other parkinsonian syndromes?
SPECT
(single photon emission computed tomography)
