Outcomes from stereotactic surgery for essential tremor

Abstract

There are several different surgical procedures that are used to treat essential tremor (ET), including deep brain stimulation (DBS) and thalamotomy procedures with radiofrequency (RF), radiosurgery (RS) and most recently, focused ultrasound (FUS). Choosing a surgical treatment requires a careful presentation and discussion of the benefits and drawbacks of each. We conducted a literature review to compare the attributes and make an appraisal of these various procedures. DBS was the most commonly reported treatment for ET. One-year tremor reductions ranged from 53% to 63% with unilateral Vim DBS. Similar improvements were demonstrated with RF (range, 74%–90%), RS (range, 48%–63%) and FUS thalamotomy (range, 35%–75%). Overall, bilateral Vim DBS demonstrated more improvement in tremor reduction since both upper extremities were treated (range, 66%–78%). Several studies show continued beneficial effects from DBS up to five years. Long-term follow-up data also support RF and gamma knife radiosurgical thalamotomy treatments. Quality of life measures were similarly improved among patients who received all treatments. Paraesthesias, dysarthria and ataxia were commonly reported adverse effects in all treatment modalities and were more common with bilateral DBS surgery. Many of the neurological complications were transient and resolved after surgery. DBS surgery had the added benefit of programming adjustments to minimise stimulation-related complications. Permanent neurological complications were most commonly reported for RF thalamotomy. Thalamic DBS is an effective, safe treatment with a long history. For patients who are medically unfit or reluctant to undergo DBS, several thalamic lesioning methods have parallel benefits to unilateral DBS surgery. Each of these surgical modalities has its own nuance for treatment and patient selection. These factors should be carefully considered by both neurosurgeons and patients when selecting an appropriate treatment for ET.

Clinical outcomes after MRI connectivity–guided radiofrequency thalamotomy for tremor

“…Other sensorimotor side effects noted were similarly mild and/or transient, suggesting that the procedure was reasonably tolerated. This is consistent with reports from other Vim lesioning surgical techniques and presumably relate to the inadvertent disruption of established anatomically related pathways, such as the dentato-thalamic tract and fibres from the ventral posterolateral thalamus 4 . We also noted dysgeusia following thalamotomy, an adverse event that has been reported following MR-guided focused ultrasound thalamotomy and presumably due to lesions overlapping with the solitario-thalamic gustatory fibers 15 .…”

Clinical outcomes after MRI connectivity–guided radiofrequency thalamotomy for tremor

“…Other sensorimotor side effects noted were similarly mild and/or transient, suggesting that the procedure was reasonably tolerated. This is consistent with reports from other Vim lesioning surgical techniques and presumably relate to the inadvertent disruption of established anatomically related pathways, such as the dentato-thalamic tract and fibres from the ventral posterolateral thalamus 4 . We also noted dysgeusia following thalamotomy, an adverse event that has been reported following MR-guided focused ultrasound thalamotomy and presumably due to lesions overlapping with the solitario-thalamic gustatory fibers 15 .…”

Suppression of Axial Tremor by Deep Brain Stimulation in Patients with Essential Tremor: Effects on Gait and Balance Measures

“…Interestingly, stride length variability reduced to the level of HC, suggesting that VIM DBS may possibly have reduced the risk of falls for these subjects although our dataset did not have a validated measure of falls to compare. Consistent with previous studies [ 1 16 27 ], DBS was effective in reducing upper limb tremor. Here, we found reduction in upper limb tremor during an overground walking and postural balance task.…”

Longitudinal follow-up with VIM thalamic deep brain stimulation for dystonic or essential tremor

“…A novel aspect of the present study is direct comparisons of DBS outcomes between DT and ET. The extent of tremor improvements in the patients with ET with VIM DBS was consistent with the previously published cohorts 16,17 and the short-and long-term outcomes were comparable between the patients with DT and patients with ET except for ADL. There was no significant difference in the percentages of good responders in the 2 groups.…”

Clinical outcomes after MRI connectivity–guided radiofrequency thalamotomy for tremor

“…Other sensorimotor side effects noted were similarly mild and/or transient, suggesting that the procedure was reasonably tolerated. This is consistent with reports from other Vim lesioning surgical techniques and presumably relate to the inadvertent disruption of established anatomically related pathways, such as the dentato-thalamic tract and fibres from the ventral posterolateral thalamus 4 . We also noted dysgeusia following thalamotomy, an adverse event that has been reported following MR-guided focused ultrasound thalamotomy and presumably due to lesions overlapping with the solitario-thalamic gustatory fibers 15 .…”

Suppression of Axial Tremor by Deep Brain Stimulation in Patients with Essential Tremor: Effects on Gait and Balance Measures

“…Interestingly, stride length variability reduced to the level of HC, suggesting that VIM DBS may possibly have reduced the risk of falls for these subjects although our dataset did not have a validated measure of falls to compare. Consistent with previous studies [ 1 16 27 ], DBS was effective in reducing upper limb tremor. Here, we found reduction in upper limb tremor during an overground walking and postural balance task.…”

Longitudinal follow-up with VIM thalamic deep brain stimulation for dystonic or essential tremor

“…A novel aspect of the present study is direct comparisons of DBS outcomes between DT and ET. The extent of tremor improvements in the patients with ET with VIM DBS was consistent with the previously published cohorts 16,17 and the short-and long-term outcomes were comparable between the patients with DT and patients with ET except for ADL. There was no significant difference in the percentages of good responders in the 2 groups.…”

Clinical outcomes after MRI connectivity–guided radiofrequency thalamotomy for tremor

“…Other sensorimotor side effects noted were similarly mild and/or transient, suggesting that the procedure was reasonably tolerated. This is consistent with reports from other Vim lesioning surgical techniques and presumably relate to the inadvertent disruption of established anatomically related pathways, such as the dentato-thalamic tract and fibres from the ventral posterolateral thalamus 4 . We also noted dysgeusia following thalamotomy, an adverse event that has been reported following MR-guided focused ultrasound thalamotomy and presumably due to lesions overlapping with the solitario-thalamic gustatory fibers 15 .…”

Suppression of Axial Tremor by Deep Brain Stimulation in Patients with Essential Tremor: Effects on Gait and Balance Measures

“…Interestingly, stride length variability reduced to the level of HC, suggesting that VIM DBS may possibly have reduced the risk of falls for these subjects although our dataset did not have a validated measure of falls to compare. Consistent with previous studies [ 1 16 27 ], DBS was effective in reducing upper limb tremor. Here, we found reduction in upper limb tremor during an overground walking and postural balance task.…”

Longitudinal follow-up with VIM thalamic deep brain stimulation for dystonic or essential tremor

“…A novel aspect of the present study is direct comparisons of DBS outcomes between DT and ET. The extent of tremor improvements in the patients with ET with VIM DBS was consistent with the previously published cohorts 16,17 and the short-and long-term outcomes were comparable between the patients with DT and patients with ET except for ADL. There was no significant difference in the percentages of good responders in the 2 groups.…”