Analysis of Semiology, Lesion Topography and Treatment Outcomes: A Prospective Study on Post Thalamic Stroke Holmes Tremor

Objective Holmes tremor (HT) comprises rest, postural and intention tremor subtypes, usually involving both proximal and distal musculature. Perturbations of nigro-striatal pathways might be fundamental in the pathogenesis of HT along with cerebel-lo-thalamic connections.Methods Nine patients with an HT phenotype secondary to thalamic stroke were included. Epidemiological and clinical re-cords were obtained. Structural and functional brain imaging were performed with magnetic resonance imaging (MRI) or com-puted tomography (CT) and positron emission tomography (PET), respectively. Levodopa was administered in sequentially in-creasing dosage, with various other drugs in case of inadequate response. Longitudinal follow-up was performed for at least three months. The essential tremor rating assessment scale (TETRAS) was used for assessment.Results The mean latency from stroke to tremor onset was 50.4 +/- 30.60 days (range 21-90 days). Dystonia was the most fre-quently associated hyperkinetic movement (88.8%). Tremor was bilateral in 22.2% of participants. Clinical response was judged based on a reduction in the TETRAS score by a prefixed value (>= 30%), pertaining to which 55.5% (n = 5) of subjects were classified as responders and the rest as non-responders. The responders showed improvement with significantly lower doses of levodopa than the remaining nonresponders (240 +/- 54.7 mg vs. 400 +/- 40.8 mg; p = 0.012).Conclusion Although levodopa is useful in HT, augmenting the dosage of levodopa beyond a certain point might not benefit patients clinically. Topography of vascular lesions within the thalamus might additionally influence the phenomenology of HT.