Outcome of Essential Tremors with Stereotactic Thalamotomy: Noble Art of Lesioning

  • AURANGZEB KALHORO Neurospinal & Cancer Care Institute
  • ABID SALEEM Neurospinal & Cancer Care Institute
  • ABDUL S ATTAR M. HASHIM Jinnah Medical and Dental College, Karachi
Keywords: Essential Tremor, Stereotactic Thalamotomy, Nucleus Ventralis Intermedius


Objective:  Objective of study is to identify the effects of Stereotactic thalamotomy of the nucleus ventral intermediate (VIM) for treatment of essential tremor.

Material and Methods:  This is a descriptive study.It was performed at NCCI, Karachi, duration of study was 7 years, from 2-10-2012 to 7-10-2019. Those patients were included who were with tremors refractory to medication, their duration of disease was > 3 years, and with grade 4 tremors. The thalamotomy was performed in all cases, and follow-up was conducted at 3, 6, and 12 months respectively. The success of the surgery was measured in the form of a reduction in medication number and reduction in dose >50% and by calculating the Essential Tremor Rating Assessment Scale (tetras).

Results:  Total of 26 patients were included. All patients showed remarkable improvement post-procedure at 12 month follow-up. 20 (77%) patient required no medications. In 6 (23%) patients, the dose of medication was reduced to less than half post-treatment. The tetras score showed marked improvement in all a patient; 4 (15%) patients who had grade 4 tremor, showed the symptoms of minimal tremors graded 0.5 on last visit 3rd visit. Side effect post-procedure were mild transient numbness on the contralateral side was observed in 11 (42.3%) patient, 1 (3.8%) patient had dysarthria.

Conclusion:  We concluded that stereostatic Ventral intermedius nucleus thalamotomy was effective in reducing tremor grades and improved all functionality with few mild side effects.


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Original Article