Parkinson's Knowledge 4 — Questions and Answers
Question 1: Which imaging technique is most commonly used to support a clinical diagnosis of Parkinson's disease by detecting dopamine transporter loss?
- MRI with contrast
- DaTscan (SPECT imaging) (Correct answer)
- CT scan of the brain
- PET scan with FDG
Correct answer: DaTscan (SPECT imaging)
DaTscan uses SPECT imaging with a radiolabeled tracer to visualize dopamine transporter levels in the striatum, helping confirm dopaminergic deficiency.
Question 2: What is dyskinesia in the context of Parkinson's disease management?
- Difficulty swallowing
- Involuntary writhing movements caused by long-term levodopa use (Correct answer)
- Extreme muscle stiffness
- Loss of balance
Correct answer: Involuntary writhing movements caused by long-term levodopa use
Levodopa-induced dyskinesia refers to involuntary, often twisting movements that develop as a complication of long-term levodopa therapy.
Question 3: Which Parkinson's symptom specifically refers to abnormally small handwriting?
- Hypomimia
- Micrographia (Correct answer)
- Bradyphrenia
- Palilalia
Correct answer: Micrographia
Micrographia is progressively small and cramped handwriting resulting from the fine motor deficits of Parkinson's disease.
Question 4: What is the role of COMT inhibitors (e.g., entacapone) in Parkinson's treatment?
- Replace lost dopamine directly
- Extend the effect of levodopa by preventing its peripheral breakdown (Correct answer)
- Stimulate dopamine receptors
- Block acetylcholine to reduce tremor
Correct answer: Extend the effect of levodopa by preventing its peripheral breakdown
COMT inhibitors block the enzyme catechol-O-methyltransferase, reducing peripheral metabolism of levodopa and extending its duration of action.
Question 5: Which Parkinson's non-motor symptom is associated with reduced sense of smell, often appearing years before motor symptoms?
- Orthostatic hypotension
- Hyposmia (anosmia) (Correct answer)
- Constipation
- Excessive daytime sleepiness
Correct answer: Hyposmia (anosmia)
Hyposmia (reduced sense of smell) is one of the earliest prodromal non-motor symptoms of Parkinson's, often predating motor signs by years.
Question 6: Which of the following best describes the gait pattern typical of Parkinson's disease?
- Wide-based, ataxic gait with arm flailing
- Shuffling steps with reduced arm swing and stooped posture (Correct answer)
- High-stepping gait with foot drop
- Scissor gait with leg crossing
Correct answer: Shuffling steps with reduced arm swing and stooped posture
Parkinson's gait is characterized by short shuffling steps, reduced arm swing, and a forward-stooped posture called festination.
Question 7: What is the significance of the retropulsion test in Parkinson's disease assessment?
- It measures dopamine receptor sensitivity
- It evaluates postural instability by testing the patient's ability to recover from a backward pull (Correct answer)
- It assesses the severity of resting tremor
- It monitors levodopa absorption rate
Correct answer: It evaluates postural instability by testing the patient's ability to recover from a backward pull
The retropulsion (pull) test assesses postural reflexes; an inability to recover from a backward push indicates significant postural instability.
Parkinson's Knowledge 4
Which imaging technique is most commonly used to support a clinical diagnosis of Parkinson's disease by detecting dopamine transporter loss?