Shannon Y Chiu1, Kamilia Nozile-Firth2, Bryan T Klassen3, Andrea Adams3, Kendall Lee4, Jamie J Van Gompel4, Anhar Hassan3. 1. Department of Neurology, Mayo Clinic, Rochester, MN, USA; Department of Neurology, University of Florida, Gainesville, FL, USA. Electronic address: Shannon.Chiu@neurology.ufl.edu. 2. Department of Neurology, BayCare Medical Group, Tampa, FL, USA. 3. Department of Neurology, Mayo Clinic, Rochester, MN, USA. 4. Department of Neurosurgery, Mayo Clinic, Rochester, MN, USA.
Abstract
BACKGROUND: Deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) thalamus is highly effective to treat medication-refractory essential tremor (ET). Complications of stimulation-induced ataxia and tolerance have been reported in limited series, ranging from 5 to 40%. OBJECTIVE: We analyzed a large single-center cohort of ET patients treated with thalamic DBS to assess rates of ataxia and tolerance. METHODS: Retrospective study of all ET patients that underwent VIM DBS at Mayo Clinic from 2010 to 2014. Demographic, clinical and DBS data were extracted. Risk factors, complications and time to onset of tolerance and ataxia were examined. RESULTS: One hundred and thirteen ET patients (51% male) of mean age 68 ± 10 years and mean ET duration 27 ± 18 years underwent DBS during the study period. Of these, 98 (87%) had follow-up of ≥6 months (mean 4.0 ± 1.5 years) and were included for analysis. Complications of isolated ataxia (26%), isolated tolerance (4%), both tolerance and ataxia (9%), or neither (61%) were identified. Development of ataxia was about 3 times more common than tolerance (35% vs. 13%). The mean time to ataxia was 5.5 ± 0.3 years postoperatively. Risk factors for ataxia were baseline ataxic features, older age, and shorter ET disease duration. Small sample size limited calculation of risk factors and onset time for tolerance. CONCLUSIONS: Stimulation-related ataxia occurred in one-third of ET patients, while tolerance was less common. Presence of baseline ataxia, age, and disease duration may aid counseling of stimulation-related ataxia risk. Larger studies are warranted to confirm these findings and further assess risk factors for tolerance. Published by Elsevier Ltd.
BACKGROUND: Deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) thalamus is highly effective to treat medication-refractory essential tremor (ET). Complications of stimulation-induced ataxia and tolerance have been reported in limited series, ranging from 5 to 40%. OBJECTIVE: We analyzed a large single-center cohort of ET patients treated with thalamic DBS to assess rates of ataxia and tolerance. METHODS: Retrospective study of all ET patients that underwent VIM DBS at Mayo Clinic from 2010 to 2014. Demographic, clinical and DBS data were extracted. Risk factors, complications and time to onset of tolerance and ataxia were examined. RESULTS: One hundred and thirteen ET patients (51% male) of mean age 68 ± 10 years and mean ET duration 27 ± 18 years underwent DBS during the study period. Of these, 98 (87%) had follow-up of ≥6 months (mean 4.0 ± 1.5 years) and were included for analysis. Complications of isolated ataxia (26%), isolated tolerance (4%), both tolerance and ataxia (9%), or neither (61%) were identified. Development of ataxia was about 3 times more common than tolerance (35% vs. 13%). The mean time to ataxia was 5.5 ± 0.3 years postoperatively. Risk factors for ataxia were baseline ataxic features, older age, and shorter ET disease duration. Small sample size limited calculation of risk factors and onset time for tolerance. CONCLUSIONS: Stimulation-related ataxia occurred in one-third of ET patients, while tolerance was less common. Presence of baseline ataxia, age, and disease duration may aid counseling of stimulation-related ataxia risk. Larger studies are warranted to confirm these findings and further assess risk factors for tolerance. Published by Elsevier Ltd.
Authors: Virgilio Gerald H Evidente; Francisco A Ponce; Maris H Evidente; Margaret Lambert; Robin Garrett; Manikandan Sugumaran; David G Lott Journal: Tremor Other Hyperkinet Mov (N Y) Date: 2020-12-31