Essential Tremor Diagnosis and Treatment

Diagnosis

The American Academy of Neurology recommends that essential tremor be diagnosed clinically based on bilateral action tremor of the arms and hands present for at least 3 years, without isolated head/voice tremor or task-specific tremor 1
Essential tremor is characterized by tremor characteristics of bilateral action tremor primarily affecting arms and hands, with frequency of 4-8 Hz 1
The diagnosis requires a duration of symptoms for at least 3 years to establish diagnosis 1
Consciousness remains intact during tremor episodes 1
Exacerbating factors include emotional stress, caffeine consumption, and physical exertion 1
Red flags requiring further workup include duration of attacks >1 minute, age of onset >20 years, abnormalities on brain CT/MRI 1

The American College of Radiology recommends that Ioflupane SPECT/CT be used to essentially exclude Parkinsonian syndromes and confirm essential tremor diagnosis 2
MRI brain is not required for diagnosis but is useful to exclude structural lesions, atrophy, or vascular disease 2
CT head is not preferred due to limited soft-tissue characterization 2

The American Academy of Neurology recommends initiating treatment only when tremor interferes with function or quality of life, starting with either propranolol (80-240 mg/day) or primidone as first-line therapy 3
Propranolol is the most established medication with 40+ years of use, effective in up to 70% of patients at doses of 80-240 mg/day 3
Primidone is an alternative first-line option, effective in up to 70% of patients 3
The American Heart Association notes that propranolol contraindications include chronic obstructive pulmonary disease, bradycardia, or congestive heart failure 3
Propranolol side effects include lethargy, depression, dizziness, hypotension, exercise intolerance, sleep disorders, cold extremities, and bronchospasm 3
The American Academy of Neurology recommends considering MRgFUS thalamotomy for unilateral tremor or patients with medical comorbidities due to lower complication rate (4.4%) 3, 4
Deep brain stimulation (DBS) is the procedure of choice for bilateral tremor 3
MRgFUS thalamotomy has a sustained tremor improvement of 56% at 4 years 3, 4
DBS provides adequate tremor control in approximately 90% of patients, with advantages including adjustable, reversible, and optimizable tremor control over time 3

Normal MRI does not exclude Parkinson's disease, as it is a clinical diagnosis, according to the American College of Radiology 5

Ioflupane SPECT/CT can be used to exclude Parkinsonian syndromes by demonstrating normal dopamine transporter uptake in the striatum, particularly when clinical examination is equivocal, as recommended by the American College of Radiology 5