Neurology: Extrapyramidal System Diseases

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Questions and Answers

What is the characteristic appearance of substantia nigra in Parkinson's disease?

Dark brown due to increased melanin

Yellowish color indicating inflammation

Pale appearance due to degeneration (correct)

Bright white due to fluid accumulation

At what age does the incidence of Parkinson’s disease peak?

In the mid-70s (correct)

In the early 80s

In the late 50s

In the late 40s

Which of the following describes the tremors associated with Parkinson’s disease?

Constant and rapid, occurring during activity

Dynamic and varying, occurring during sleep

Fine and fast, consistent throughout the day

Coarse and rhythmic, appearing at rest (correct)

Which of the following accurately describes rigidity in Parkinson's disease?

Increased resistance with a cogwheel character Signup and view all the answers

What is often considered the first and most disabling symptom of Parkinson's disease?

Hypokinesis (bradykinesia) Signup and view all the answers

What identifiable feature is most strongly associated with the mobility issues of patients with Parkinson's disease?

Postural instability Signup and view all the answers

What phenomenon can occur after prolonged use of Levodopa in patients with Parkinson's disease?

On-off effect Signup and view all the answers

Which characteristic differentiates essential or familial tremors from Parkinson's disease?

Age of onset Signup and view all the answers

Which symptom is NOT typically an early sign of Parkinson's disease?

Postural instability Signup and view all the answers

What impact does emotional upset have on tremors in Parkinson’s disease?

Increases tremor intensity Signup and view all the answers

What is a common side effect of Levodopa when used as a treatment for Parkinson's disease?

Nausea Signup and view all the answers

What is the familial incidence rate of Parkinson's disease?

5% Signup and view all the answers

Which imaging techniques have improved the diagnostic accuracy of Parkinson's disease?

PET and SPECT Signup and view all the answers

Which of the following nuclei is NOT considered part of the basal ganglia?

Thalamus Signup and view all the answers

What is a known effect of anticholinergic drugs used in treating tremors associated with Parkinson's disease?

Blurring of vision Signup and view all the answers

What combination of medications is usually prescribed to enhance the effectiveness of Levodopa?

Levodopa and Carbidopa Signup and view all the answers

Which of the following is a common treatment option for patients experiencing hypokinesis due to Parkinson's disease?

Bromocriptine Signup and view all the answers

What is the primary neurotransmitter whose deficiency is associated with Parkinson's disease?

Dopamine Signup and view all the answers

Which symptom is NOT typically associated with Parkinson's disease?

Hyperkinesis Signup and view all the answers

In the context of Parkinson's disease, what role does acetylcholine play?

Exerts an excitatory effect Signup and view all the answers

Which statement accurately describes dystonia?

It is characterized by sustained muscle contractions leading to abnormal posture Signup and view all the answers

Which of the following describes the final pathway for basal ganglia motor function?

Corticospinal tract Signup and view all the answers

What is the primary treatment approach for rheumatic chorea?

Psychological support and monitoring Signup and view all the answers

What is the term used for decreased voluntary movements seen in Parkinson's disease?

Hypokinesis Signup and view all the answers

What characterizes the movements observed in chorea?

Sudden, jerky, and irregular movements Signup and view all the answers

Which condition is NOT categorized as an extrapyramidal syndrome?

Multiple sclerosis Signup and view all the answers

What is a potential trigger for the degeneration of the substantia nigra in Parkinson’s disease?

Repeated head trauma Signup and view all the answers

What is the pronator sign associated with?

Hyperpronation of the arm on the affected side Signup and view all the answers

What is a common trigger for the exacerbation of choreiform movements?

Emotional stress Signup and view all the answers

Which drug is known to decrease dopamine activity in the basal ganglia for movement control?

Haloperidol Signup and view all the answers

Which of the following is a common side effect of amantadine hydrochloride?

Vasodilatation Signup and view all the answers

What might dysarthria result from in the context of chorea?

Involuntary movements affecting respiratory and laryngeal muscles Signup and view all the answers

What is the primary action of amantadine hydrochloride?

It stimulates endogenous dopamine. Signup and view all the answers

Which symptoms are indicative of hyperkinesis?

Excessive and exaggerated arm movements during activities Signup and view all the answers

In the context of Sydenham's chorea, which of the following is true regarding its etiology?

It results from an immunological reaction to the M protein of group A beta streptococcus. Signup and view all the answers

What treatment may be helpful in managing unilateral tremor refractory to medical treatment?

Stereotactic thalamotomy Signup and view all the answers

What is a significant difference between chorea and Parkinson’s disease?

Chorea results from increased dopamine activity in the basal ganglia. Signup and view all the answers

Which of the following statements is true about the demographic affected by rheumatic chorea?

It predominantly affects girls during childhood and adolescence. Signup and view all the answers

What characterizes the movements seen in chorea?

Irregular, low amplitude jerking movements. Signup and view all the answers

Which characteristic is NOT a result of Sydenham's chorea?

Permanent neurological damage. Signup and view all the answers

Study Notes

Diseases of the Extrapyramidal System

Voluntary movement regulation involves the pyramidal, cerebellar, and extrapyramidal systems, interconnected nodes critical for motor coordination.
The extrapyramidal system consists of several nuclei, primarily the basal ganglia, which include:
- Caudate nucleus
- Lentiform nucleus (globus and putamen)
- Substantia nigra
- Subthalamic nucleus
The thalamus is essential for relaying information between basal ganglia and the motor cortex.
Common extrapyramidal syndromes include Parkinson’s disease, rheumatic or Sydenham’s chorea, and dystonia with athetosis.

Parkinson’s Disease

First described as "shaking palsy" by James Parkinson in 1817.
Affects about 1% of people over 60 years; incidence peaks in mid-70s.
Symptoms include tremors, rigidity, and hypokinesis, all responsive to levodopa treatment.
Etiology:
- Associated with genetic mutations (Synuclein, Parkin, LRRK2) in familial cases.
- Characterized by depletion of dopamine in the substantia nigra, leading to predominance of acetylcholine's excitatory action.
Pathologic features:
- Loss of pigmented neurons in substantia nigra.
- Presence of Lewy bodies, eosinophilic inclusions in neurons.
Clinical features include:
- Tremors: Begin in fingers, may spread; visible at rest, decrease with movement.
- Rigidity: Increase in muscle resistance; can be lead-pipe or cogwheel type.
- Hypokinesis (Bradykinesia): Delay in movement initiation, characteristic shuffling gait.
- Postural Instability: Difficulty maintaining balance, can be severely disabling.
Diagnosis often requires functional imaging (PET, SPECT) for accuracy.
Differential diagnoses include essential tremor, hypothyroidism, cerebellar tremors, and metabolic issues.
Treatment options:
- Anticholinergic drugs: Limited effects on hypokinesis, significant side effects.
- Levodopa: Effective for hypokinesia; combined with Carbidopa to enhance efficacy and reduce side effects.
- Dopamine receptor agonists: Stimulate dopamine receptors and reduce levodopa dosage requirement.
- Amantadine: Mild effects on symptoms; may cause confusion or seizures.
- Surgical treatment: Reserved for severe, resistant cases.

Rheumatic or Sydenham’s Chorea

Sydenham’s chorea linked to rheumatic fever; first described by Dr. Thomas Sydenham in the 17th century.
Defined by rapid, irregular movements affecting extremities and face; movements may appear purposeful.
Common in children and adolescents, especially females; usually follows a streptococcal infection.
Etiology involves an autoimmune response triggered by group A beta-hemolytic streptococci, leading to increased dopamine activity in basal ganglia.
Clinical features include:
- Hypotonia, muscular weakness, emotional disturbances, behavioral changes, and jerky involuntary movements.
- Diagnostic signs: hyperpronation of the arm (pronator sign) and difficulty holding the tongue out (tongue sign).
Generally self-limiting, yet can relapse following streptococcal infections.
Treatment involves managing movements with:
- Haloperidol: Decreases dopamine activity; gradually adjusted for control.
- Diazepam: For severe cases, may require hospitalization.
- Penicillin: Antibiotic for throat infections; steroids may be necessary in resistant cases.

Dystonia and Athetosis

Dystonia: Characterized by sustained muscle contractions causing twisting movements and abnormal postures; involves simultaneous contraction of agonist and antagonist muscles.
Movements are repetitive and can significantly impair mobility and coordination.

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Description

This quiz explores the diseases related to the extrapyramidal system in neurology. It covers the interactions between pyramidal, cerebellar, and extrapyramidal systems that influence voluntary movement. Test your knowledge on the basal ganglia and their neural connections.