Does lesioning surgery have a role in the management of multietiological tremor in the era of Deep Brain Stimulation?

• The largest series of lesional surgery for movement disorders from India.
• Deals with varying etiologies of tremor including rare causes such as PKAN, MS and Wilson disease.
• Excellent results can be obtained with meticulous planning and target selection.
• Lesioning still is of relevance when patients cannot afford DBS.

IntroductionSurgical management of tremor has evolved over the years with Deep Brain Stimulation (DBS) gradually supplanting lesioning as the mainstay in treatment. In this article, the largest of its kind from our country, we present our experience in the use of lesioning in the management of patients with multietiological tremors. These include not only common indications like Parkinson disease and essential tremor but also rare causes such as Pantothenate kinase associated neurodegeneration (PKAN), multiple sclerosis (MS) and Wilson disease.Materials and methodsPatients with medically refractory tremor who underwent surgery were included in the analysis. A comprehensive clinical and radiological evaluation was performed which was repeated 3 months postoperatively and at successive visits. Video documentation of was obtained at all visits.ResultsA total of 21 patients (18 men, 3 women) with an average age 37.7 years (range 21–65 years) underwent stereotactic thalamotomy/subthalamotomy at our institute between 2008 and 2013, for the treatment of medically refractory tremor of varying etiologies. The mean preoperative duration of symptoms was 11 years (range 10 months to 34 years). The median time to onset of improvement was 2 months (range 1 week to 8 months). Analyzing the improvement on the modified FTM scale, in part 1 the scores improved from 21.7 to 1.5, the part II subset improved from an average of 9.2 to 3.2 while the part III subset improved from an average of 14.1 to 4.1 postoperatively. This implied an excellent response in tremor while the other 2 components had a very good response.DiscussionIn this study we have for the first time objectively analyzed the tremor improvement with a modified FTM scale and have produced excellent results. We have also shown that tremor of various etiologies respond extremely well to lesioning surgery. While DBS continues to remain the treatment of choice in various types of bilateral tremor, lesioning is very successful in a carefully selected cohort of patients. We are of the opinion that in predominantly unilateral tremor or when the patient cannot afford DBS especially in a country like ours, lesioning surgery is an important tool in the armamentarium of the functional neurosurgeon.