Parkinson's Disease

Question 1

What is the pathophysiological and macroscopical aspect of parkinsons disease?

Answer 1

loss of pigmented dopamine neurons in striatum, because no input from subst. nigra&raquo_space; less inhibition of GPi, making it overreactive&raquo_space;increased inhibtion of thamalus&raquo_space; hypokinesia

decreased pigmentation on substantia nigra and locus ceruleus
lewy bodies: abnormal aggragation of proteins

Question 2

Which mechanisms lead to neuronal loss in PD?

Answer 2

oxidative stress
mitochondrial dysfunction
excitotoxicity
glial cell activation
apoptosis

Question 3

What is parkinsons disease?

Answer 3

progressive, multifocal neurodegenerative disease

• dopaminergic/non dopaminergic
• CNS/ PNS affected

Question 4

How is the progression of the lewy inclusion bodies?

Answer 4

typical pregression from: medulla&raquo_space; pons&raquo_space; midbrain&raquo_space; mesocortex&raquo_space; neocortex

Question 5

Etiology of parkinson disease

Answer 5

genes, toxins, endogenous, trauma

Question 6

Epidemiology of parkinson disease

Answer 6

onset: 40 - 70 yea, peak in 6th decade

M>F

Question 7

What are the early signs of parkinson disease

Answer 7

• stiffness
• pain and paresthesia of limb
• constipation
• sleeplessness
• decr. voice volume

others: decr. fine motor skills and sense of smell, loss of appetite, tremor with anxiety

Question 8

Clinical subtypes of parkinson disease

Answer 8

• young age and slow progression
• old age and fast progression
• tremor dominant
• postural instability and gait difficulty

Question 9

How is the posture of a patient in parkinson disease

Answer 9

flexed posture, less of reflexes, no balance, festination, freezing phenomenon

Question 10

What are the clinical signs of dementia with lewy bodies

Answer 10

• fluctuating attention and alertness episodes
• halluzinations
• parkinsonian motor features
• early extrapyr. features (in alzheimer they are late)
• less prominent anterograde memory loss (in alzheimer is prominent)
• executive function deficits

Question 11

How to differentiate between dementia with lewy bodies and parkinson disease?

Answer 11

parkinson: parkinsonian signs are present more than 12 month before cognitive impairment

DLB: parkinsonian signs are seen less than 12 month before cognitive impairment

Question 12

Treatment of parkinsons disease

Answer 12

dopaminergic agents:

• levodopa
• dopamine agonists (ergot and non-ergot)
• selective MAO-B inhibitors

non dopamin. agents:

• anticholinergic agents
• n-methyl-di-aspartate antagonist

Question 13

describe pyramidal spasticity and parkinsonian rigidity

Answer 13

spasticity:
lesion in corticospinal pathway, unidirectional, passive movement speed dependent, UMN lesion
claspknife phenomenon: initial rigidity during passive movement, at sharp angel resistance disappears suddenly

rigidity:
extrapyramidal lesion, referred to lesion in basal ganglia, bidirectional, not speed dependent, rigidity present during whole passive movement,
leadpipe rigidity: rigidity from beginning to end of movement
cogwheel rigidity: rigidity with interposed tremor signs (parkinon feature)
plasticity: newly places limb stays in that position

Question 14

features of parkinson tremor

Answer 14

typical rest tremor, 4 - 6 Hz
most prominent at distal part of extremity
pill rolling tremor
exacerbated during provocation

Question 15

features of progressive supranuclear palsy

Answer 15

supranuclear ophtalmoplegia
pseudobulbar palsy
prominent neck dystonia
parkinsonism
impaired postural reflexes

Question 16

which motor sign is necessary for the positive diagnosis of parkinson

Answer 16

bradykinesia

additional: rigidity, 4-6 Hz tremor, postural instability with exclusion on any other possible cause

Question 17

drug of choice for psychosis in parkinsonism?

Answer 17

levodopa

Question 18

what are the sideeffects of levodopa treatment?

Answer 18

• short HL causes motor and nonmotor fluctuations (gait and postural difficulties, depression, dementia)
• dyskinesia
• neurological problems: hallizin., behavioral disorders
• daytime sleepiness

Question 19

which are the motor fluctuations in parkinson?

Answer 19

gait difficulties
postural imbalance
dysarthria

due to short HL, pulsatile dopaminergic stimulation and changes in postsynaptic receptors
reduces sythesis, storage and release of dopamine