Essential tremor – symptoms, diagnosis and treatment
Essential tremor is a common movement disorder with bilateral upper limb action tremor as leading symptom. Other mild neurological signs, such as slight ataxia or rest tremor, can be seen. The existence of non-motor symptoms, such as depression, anxiety and cognitive problems is common, especially in the advanced stage, affecting quality of life even more than the tremor.
The clinical examination is the basis for diagnosis. Besides neurological examination, the examiner should also evaluate cognition and mood. Imaging studies are not necessary if no atypical signs are present.
Half of the patients benefit from oral medicines. Commonly used medicines are propranolol, primidone, topiramate and gabapentin. Tremor is alleviated by 30–70% on average but side effects often prevent the effective use of medicines. The patient can use two or more medicines to increase efficacy. In addition, physical and occupational therapy and supportive discussions can increase understanding of the disease and quality of life.
Deep brain stimulation (DBS) effectively alleviates severe drug resistant essential tremor. Directional DBS (dDBS) using novel directional electrode technology appears to reduce stimulation related side effects such as dysarthria. Several programming sessions are needed to identify the optimal settings. Thalamotomy and high intensity focused ultrasound (HIFU) can be used when DBS is contraindicated.
Rebekka Ortiz, Jari Honkaniemi, Eero Pekkonen
M.D., Ph.D., Specialist in Neurology and General Practice
Neurology Department, Tampere University Hospital