ParkinsonTremor

ParkinsonTremor refers to the tremor commonly seen in Parkinson's disease. It is typically a rest tremor, often described as pill-rolling, with onset on one side. The tremor frequency is usually 4–6 Hz and tends to be more prominent at rest, diminishing with purposeful movement and sleep. It is usually asymmetric early in the disease but may become bilateral over time.

Pathophysiology: ParkinsonTremor stems from degeneration of dopaminergic neurons in the substantia nigra pars compacta, leading to disrupted basal ganglia circuits. Lewy body pathology is characteristic of Parkinson's disease, though the exact tremor mechanism is not fully understood and likely involves multiple networks.

Diagnosis: ParkinsonTremor is diagnosed clinically based on history and examination. The presence of bradykinesia with rest tremor is characteristic. Diagnostic criteria from professional societies may be used; imaging is supportive but not diagnostic.

Differential diagnosis: Essential tremor, dystonic tremor, drug-induced tremor, cerebrocerebellar disorders, and other parkinsonian syndromes.

Management: Levodopa is the most effective treatment for parkinsonian tremor. Other options include dopamine agonists, MAO-B inhibitors, amantadine, and anticholinergics in selected patients. For tremor-dominant PD, deep brain stimulation of the subthalamic nucleus or globus pallidus internus, or focused ultrasound thalamotomy, can be considered. Nonpharmacologic approaches include physical and occupational therapy and regular exercise.

Prognosis and research: Tremor may respond to therapy but often evolves with disease progression. Ongoing research seeks better understanding of tremor mechanisms and new therapies.