Term
| what is the pyramidal system? |
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Definition
| the lateralcorticospinal tract |
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Term
| what is the extrapyramidal system? |
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Definition
| the area of the central nervous system other than pyramidal cells of the cerebral cortex which exert control over movement - basal ganglia, cerebellum, and the smaller nucleii (subthalamic nucleus, substantia nigra, and locus cereleus). disease here = movement disorders. |
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Term
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Definition
| the caudate and putamen (internal NT is ACh) |
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Term
| what are the putamen and the globus pallidus? |
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Definition
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Term
| what is the interaction between the striatum and substantia nigra? |
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Definition
| the substantia nigra sends dopamine to the striatum. the striatum sends GABA to the substantia nigra. |
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Term
| what NT balance leads to hypokinesia? |
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Definition
| less dopamine than ACh/GABA (tx w/anticholinergic) |
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Term
| what NT balance leads to hyperkinesia? |
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Definition
| more dopamine than ACh/GABA (give cholinergic or dopamine blocker) |
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Term
| is the tremor in parkinsons functionally limiting? |
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Definition
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Term
| what is the most common tremor? tx? |
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Definition
| postural tremor - familial (autosomal dominant). tx: propanolol (beta blocker), primidone (may be better for elderly pts), and small amounts of alcohol |
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Term
| what is the most disabling tremor? |
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Definition
| the cerebellar (intention) tremor, which increases in amplitude as the target is approached. the lesion is in the dentate nuclei. etiologies: MS, cerebellar degenerations, wilson's (wing beating tremor), cerebellar or brainstem strokes. |
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Term
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Definition
| a state of *motor hyperactivity in which the speed amplitude and frequency of bodily movements are increased*. athetosis: slow forceful, writhing movement. ballismus: rapid, flinging movmement. etiologies: huntingtons, wilsons, neuroleptics, l-dopa. tx: decrease dopamine (haloperidol, reserpine) |
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Term
| what characterizes huntington's disease? |
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Definition
| facial dyskinesia, frequent blinking, "piano playing" fingers, dementia. tx: tetrabenzine. autosomal dominant. |
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Term
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Definition
| prolonged movements, often twisting - which distorts body parts. **often a sustained position at the end of a movement**. distribution can be focal (blepharospasm, oromandibular, torticollis, graphospasm), multifocal, or generalized. classification: primary (hereditary torision dystonia) or secondar (wilson's dx, neurleptics). tx: focal (botulinum), or high dose anticholinergics. |
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Term
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Definition
| a rapid, sudden, unexpected movement (sound/vocal utterance) which can be suppressed for brief periods - but doing this is like trying not to "scratch an itch" |
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Term
| what is tourette's syndrome? |
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Definition
| multiple tics, which always involve part of the head. coprolalia, echolalia, pallilalia, echokinesis. tx: haloperidol (effective, but troublesome for younger pts), clonidine. onset in childhood. worsens w/stress. |
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Term
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Definition
| sudden, shock-like movements of single groups of musculature. focal: due to local nerve irritation (hiccups, eyelids etc) or generalized: post-anoxic encephalopathy, uremia, jakob-creutzfeld disease (mad cow), hypocalcemia (think metabolic - pts w/uremic disease, kidney disease or hepatic failure: twitch-convulsion syndrome). |
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Term
| what is the clinical presentation of parkinson's disease? |
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Definition
| akinesia, rigidity, and tremor (also: postural instability, dementia, orthostatic hypotension (many drugs may aggravate this), and REM behavioral sleep disorder) |
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Term
| what characterizes the akinesia seen in parkinson's? |
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Definition
| mask-like facies (paucity of blinking), microphonia, micrographia, difficulty in initiating movement, shuffling gait (reduced arm swing), and festinating (involuntary accelerating w/shuffle + inability to decelerate) |
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Term
| what characterizes the rigidity in parkinson's disease? |
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Definition
| cogwheel-type, lead pipe when advanced (ratcheting feeling in wrist) |
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Term
| what characterizes the tremor in parkinson's? |
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Definition
| resting: disappears/decreases w/movement. embarassing, but not functionally limiting like akinesia/rigidity. may involve hands (pill rolling), mandible, or legs. |
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Term
| what is the pathogenesis of parkinsons? |
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Definition
| degeneration of substantia nigra, pars compacta – loss of dopaminergic neurons. MPTP, insecticides and genetics also can play part. cigarettes help protect against it. |
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Term
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Definition
| *anti-cholinergics [cogentin/artane] for tremor particularly in young people (ADRs: dry mouth, difficulty with visual accommodation, blurred vision and can’t read, may get confused (elderly)), but won't help w/rigidity. *amantadine [symmetrel - antiviral]: increases dopamine synthesis, decreases re-uptake, post-synaptic stimulation. beneficial effects are short lived, often added to anti-ACh. *l-dopa+carbidopa [simemet 100/25]: carbidopa b/c it prevents peripheral decarboxylation of l-dopa to dopamine which gives a lot of side effects like nausea. COMT inhibitors may also be used to keep l-dopa from being broken down via the carboxy-methyl transferase pathway (extends sinemet duration another 4 hrs). l-dopa is **most effective w/rigidity and akinesia**. (ADRs:n/v, confusion, hallucinations, dose related dyskinesias, on-off phenomenon [last 2 - major long term problems]). *dopamine agonists: bromocriptine, pergolide, requip, mirapex, neupro - all of which postsynaptically stimulate the dopamine receptor - presently used to permit reduction of l-dopa dosage in certain situations (young pts, pts w/l-dopa-induced dyskinesias/on-off, initial use of dopamine agonists delays need for l-dopa and may lessen development of l-dopa induced side-effects. ADRs: hypotension, confusion, hallucinations. *MAO-B inhibitors: seligeline/rasagline which prevent breakdown of l-dopa, may prevent build-up of toxic metabolites, possibly neuroprotective, and mild dopamine agonist. *stem cell transplantation |
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Term
| what are secondary causes of parkinson's? |
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Definition
| antipsychotics (tx w/anticholinergics), metoclopramide, post-encephalitis, and manganese intoxication (welders) |
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Term
| what is the association between REM sleep disorders and parkinson's? |
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Definition
| if a bed partner acts out in the middle of night lashes out and screams, might have REM sleep behavioral disorder – there’s a 50% chance they will develop parkinson’s disease in 15 years. REM sleep behavior disorder is possibly earliest manifestations of a synucleinopathies of which parkinson's is the most common. |
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