Prediction of Clinical Deep Brain Stimulation Target for Essential Tremor From 1.5 Tesla MRI Anatomical Landmarks

Background: Deep brain stimulation is an efficacious treatment for refractory essential tremor, though targeting the intra-thalamic nuclei remains challenging.Objectives: We sought to develop an inverse approach to retrieve the position of the leads in a cohort of patients operated on with optimal clinical outcomes from anatomical landmarks identifiable by 1.5 Tesla magnetic resonance imaging.Methods: The learning database included clinical outcomes and post-operative imaging from which the coordinates of the active contacts and those of anatomical landmarks were extracted. We used machine learning regression methods to build three different prediction models. External validation was performed according to a leave-one-out cross-validation.Results: Fifteen patients (29 leads) were included, with a median tremor improvement of 72% on the Fahn–Tolosa–Marin scale. Kernel ridge regression, deep neural networks, and support vector regression (SVR) were used. SVR gave the best results with a mean error of 1.33 ± 1.64 mm between the predicted target and the active contact position.Conclusion: We report an original method for the targeting in deep brain stimulation for essential tremor based on patients' radio-anatomical features. This approach will be tested in a prospective clinical trial.

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Thalamic organization in essential tremor patients with neuropathy: implication for functional neurosurgery

10.1101/2021.02.21.21251847 ◽

2021 ◽

Author(s):

Francesco Sammartino ◽

Vinayak Narayan ◽

Barbara Changizi ◽

Aristide Merola ◽

Vibhor Krishna

Keyword(s):

Deep Brain Stimulation ◽

Essential Tremor ◽

Clinical Outcomes ◽

Brain Stimulation ◽

Element Model ◽

Target Coverage ◽

Thalamic Nuclei ◽

Intermediate Nucleus ◽

Ventral Intermediate Nucleus ◽

Deep Brain

AbstractBackgroundMechanisms underlying the suboptimal effect of ventral intermediate nucleus deep brain stimulation in patients with essential tremor and co-morbid peripheral neuropathy remain unclear.ObjectivesWe compared disease-related (location and extension of the ventral intermediate nucleus) and surgery-related (targeting, intraoperative testing) factors in essential tremor patients with and without peripheral polyneuropathy treated with deep brain stimulation of the ventral intermediate nucleus, testing whether the overlap between volume of tissue activated and ventral intermediate nucleus (target coverage) was associated with clinical outcomes.MethodsPreoperative diffusion magnetic resonance imaging was used for thalamic segmentation, based on preferential cortical connectivity. The target coverage was estimated using a finite element model. Tremor severity was scored at rest, posture, action, and handwriting at baseline, 6, and 12 months. Tremor improvement <50% at 12 months was deemed suboptimal. Vertex-wise shape analysis and edge analysis were performed to compare the ventral intermediate nucleus location and extension.Results9.7% (18/185) of essential tremor patients treated with deep brain stimulation had co-morbid polyneuropathy. These patients showed a more medial (p=0.03) and anterior (p=0.04) location of the ventral intermediate nucleus, lower target coverage (p=0.049), and worse clinical outcomes (p=0.006) compared to those without polyneuropathy. No differences were observed in the volume of tissue activated between the two groups. Optimal clinical outcomes were associated with greater target coverage (optimal coverage >48%).ConclusionsIn essential tremor, co-morbid polyneuropathy may result in suboptimal deep brain stimulation outcomes and lower target coverage, likely related to a reorganization of the ventral thalamic nuclei.

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Deep brain stimulation in essential tremor: targets, technology, and a comprehensive review of clinical outcomes

Expert Review of Neurotherapeutics ◽

10.1080/14737175.2020.1737017 ◽

2020 ◽

Vol 20 (4) ◽

pp. 319-331 ◽

Cited By ~ 1

Author(s):

Joshua K. Wong ◽

Christopher W. Hess ◽

Leonardo Almeida ◽

Erik H. Middlebrooks ◽

Evangelos A. Christou ◽

...

Keyword(s):

Deep Brain Stimulation ◽

Essential Tremor ◽

Clinical Outcomes ◽

Brain Stimulation ◽

Comprehensive Review ◽

Deep Brain

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Use of quantitative tremor evaluation to enhance target selection during deep brain stimulation surgery for essential tremor

Current Directions in Biomedical Engineering ◽

10.1515/cdbme-2015-0117 ◽

2015 ◽

Vol 1 (1) ◽

pp. 488-492 ◽

Cited By ~ 1

Author(s):

A. Shah ◽

J. Coste ◽

JJ. Lemaire ◽

E. Schkommodau ◽

S. Hemm-Ode

Keyword(s):

Deep Brain Stimulation ◽

Essential Tremor ◽

Brain Stimulation ◽

Quantitative Methods ◽

Evaluation Method ◽

Target Selection ◽

Thalamic Nuclei ◽

Visual Evaluation ◽

Test Stimulation ◽

Deep Brain

AbstractDeep brain stimulation (DBS), an effective surgical treatment for Essential Tremor (ET), requires test stimulations in the thalamus to find the optimum site for permanent electrode implantation. During these test stimulations, the changes in tremor are only visually evaluated. This, along with other parameters, increases the subjectivity when comparing the efficacy of different thalamic nuclei. We developed a method to quantitatively evaluate tremor during the test stimulations of DBS surgery and applied to 6 ET patients undergoing this treatment. From the quantitative data collected, we identified effective stimulation amplitudes for every test stimulation position and compared it with the ones identified visually during the surgery. We also classified the data based on the thalamic nuclei in which the center of the stimulating contact was present during test stimulations. Results indicate that, to achieve the same reduction in tremor, on average, the stimulation amplitude identified by our method was 0.6 mA lower than those identified by visual evaluation. The comparison of the different thalamic nuclei showed that stimulations in the Ventro-oral and the Intermediolateral nuclei of the thalamus result in higher reduction in tremor for similar stimulation amplitudes as the frequently targeted Ventrointermediate nucleus. We conclude that our quantitative tremor evaluation method is more sensitive than the widely used visual evaluation. Using such quantitative methods will aid in identifying the optimum target structure for patients undergoing DBS.

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Cyclic Deep Brain Stimulation in Essential Tremor

Case Medical Research ◽

10.31525/ct1-nct04260971 ◽

2020 ◽

Author(s):

Keyword(s):

Deep Brain Stimulation ◽

Essential Tremor ◽

Brain Stimulation ◽

Deep Brain

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High-fidelity transmission of high-frequency burst stimuli from peripheral nerve to thalamic nuclei in children with dystonia

Scientific Reports ◽

10.1038/s41598-021-88114-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Estefanía Hernandez-Martin ◽

Enrique Arguelles ◽

Yifei Zheng ◽

Ruta Deshpande ◽

Terence D. Sanger

Keyword(s):

Deep Brain Stimulation ◽

Peripheral Nerve ◽

Brain Stimulation ◽

High Frequency ◽

Sensory Information ◽

Brain Structures ◽

High Fidelity ◽

Thalamic Nuclei ◽

Frequency Burst ◽

Deep Brain

AbstractHigh-frequency peripheral nerve stimulation has emerged as a noninvasive alternative to thalamic deep brain stimulation for some patients with essential tremor. It is not known whether such techniques might be effective for movement disorders in children, nor is the mechanism and transmission of the peripheral stimuli to central brain structures understood. This study was designed to investigate the fidelity of transmission from peripheral nerves to thalamic nuclei in children with dystonia undergoing deep brain stimulation surgery. The ventralis intermediate (VIM) thalamus nuclei showed a robust evoked response to peripheral high-frequency burst stimulation, with a greatest response magnitude to intra-burst frequencies between 50 and 100 Hz, and reliable but smaller responses up to 170 Hz. The earliest response occurred at 12–15 ms following stimulation onset, suggesting rapid high-fidelity transmission between peripheral nerve and thalamic nuclei. A high-bandwidth, low-latency transmission path from peripheral nerve to VIM thalamus is consistent with the importance of rapid and accurate sensory information for the control of coordination and movement via the cerebello-thalamo-cortical pathway. Our results suggest the possibility of non-invasive modulation of thalamic activity in children with dystonia, and therefore the possibility that a subset of children could have beneficial clinical response without the need for invasive deep brain stimulation.

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