Whole-brain modeling to predict optimal deep brain stimulation targeting

Background: Neuronal loss in Parkinson’s Disease (PD) leads to widespread neural network dysfunction. While graph theory allows for analysis of whole brain networks, patterns of functional connectivity (FC) associated with motor response to deep brain stimulation of the subthalamic nucleus (STN-DBS) have yet to be explored.Objective/Hypothesis: To investigate the distributed network properties associated with STN-DBS in patients with advanced PD.Methods: Eighteen patients underwent 3-Tesla resting state functional MRI (rs-fMRI) prior to STN-DBS. Improvement in UPDRS-III scores following STN-DBS were assessed 1 year after implantation. Independent component analysis (ICA) was applied to extract spatially independent components (ICs) from the rs-fMRI. FC between ICs was calculated across the entire time series and for dynamic brain states. Graph theory analysis was performed to investigate whole brain network topography in static and dynamic states.Results: Dynamic analysis identified two unique brain states: a relative hypoconnected state and a relative hyperconnected state. Time spent in a state, dwell time, and number of transitions were not correlated with DBS response. There were no significant FC findings, but graph theory analysis demonstrated significant relationships with STN-DBS response only during the hypoconnected state – STN-DBS was negatively correlated with network assortativity.Conclusion: Given the widespread effects of dopamine depletion in PD, analysis of whole brain networks is critical to our understanding of the pathophysiology of this disease. Only by leveraging graph theoretical analysis of dynamic FC were we able to isolate a hypoconnected brain state that contained distinct network properties associated with the clinical effects of STN-DBS.

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Clinically Weighted Probabilistic Tractography Mapping of Therapeutic Thalamic Deep Brain Stimulation for Essential Tremor

Neurosurgery ◽

10.1093/neuros/nyz310_364 ◽

2019 ◽

Vol 66 (Supplement_1) ◽

Author(s):

Evangelia Tsolaki ◽

Alon Kashanian ◽

Nader Pouratian

Keyword(s):

Deep Brain Stimulation ◽

Clinical Outcome ◽

Essential Tremor ◽

Clinical Improvement ◽

Brain Stimulation ◽

Structural Connectivity ◽

Precentral Gyrus ◽

Probabilistic Tractography ◽

Whole Brain ◽

Deep Brain

Abstract INTRODUCTION Traditional targeting methods rely on indirect targeting with atlas-defined coordinates that induce interpatient anatomical and functional variability. Precise targeting is crucial for successful surgical intervention associated with improved surgical outcomes. Here, we use clinically weighted probabilistic tractography to investigate the connectivity from volume of tissue activated (VTA) to whole brain in order to evaluate the relationship between structural connectivity and clinical outcome of patients that underwent thalamic deep brain stimulation (DBS). METHODS Magnetic resonance imaging and clinical outcomes from 10 essential tremor (ET) patients who were treated by VIM-DBS at the University of California Los Angeles were evaluated. LeadBDS was used for the VTA calculation and FSL was used to evaluate the whole brain probabilistic tractography of VTA. Tractography maps were binarized and weighted based on the percent of clinical improvement using the Fahn-Tolosa-Martin Tremor Rating Score. The resulting clinically weighted maps were non-linearly fused to MNI space and averaged. These population maps provide a voxel-by-voxel map of the average clinical improvement observed when the VTA demonstrates structural connectivity to the whole brain. RESULTS The VTA connectivity to the whole brain was delineated. Superior clinical improvement was associated with connectivity to voxels connecting the thalamus to the precentral gyrus and to the brainstem/cerebellum. Also, the clinical efficacy map showed that patients with higher clinical improvement (>70%) presented stronger structural connectivity to the precentral gyrus and to the caudal projection to the cerebellum. CONCLUSION Stronger connectivity to the precentral gyrus and to brainstem/cerebellum is associated with superior clinical outcome in thalamic DBS for ET. In the future, rather than focusing on connectivity to predetermined targets, these clinically weighted tractography maps can be used with a reverse algorithm to identify the optimal region of the thalamus to provide clinically superior results.

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Uncovering the underlying mechanisms and whole-brain dynamics of therapeutic deep brain stimulation for Parkinson's disease

10.1101/083162 ◽

2016 ◽

Author(s):

Victor M Saenger ◽

Joshua Kahan ◽

Tom Foltynie ◽

Karl Friston ◽

Tipu Z Aziz ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Deep Brain Stimulation ◽

Brain Stimulation ◽

Resting State Fmri ◽

Brain Regions ◽

Brain Dynamics ◽

Whole Brain ◽

Underlying Mechanisms ◽

Deep Brain

Deep brain stimulation (DBS) for Parkinson's disease is a highly effective treatment in controlling otherwise debilitating symptoms yet the underlying brain mechanisms are currently not well understood. We used whole-brain computational modeling to disclose the effects of DBS ON and OFF during collection of resting state fMRI in ten Parkinson's Disease patients. Specifically, we explored the local and global impact of DBS in creating asynchronous, stable or critical oscillatory conditions using a supercritical bifurcation model. We found that DBS shifts the global brain dynamics of patients nearer to that of healthy people by significantly changing the bifurcation parameters in brain regions implicated in Parkinson's Disease. We also found higher communicability and coherence brain measures during DBS ON compared to DBS OFF. Finally, by modeling stimulation we identified possible novel DBS targets. These results offer important insights into the underlying effects of DBS, which may in time offer a route to more efficacious treatments.

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Subcallosal Cingulate Deep Brain Stimulation for Treatment-Resistant Unipolar and Bipolar Depression

Yearbook of Neurology and Neurosurgery ◽

10.1016/j.yneu.2012.05.058 ◽

2012 ◽

Vol 2012 ◽

pp. 241-243

Author(s):

P. House

Keyword(s):

Deep Brain Stimulation ◽

Brain Stimulation ◽

Bipolar Depression ◽

Treatment Resistant ◽

Deep Brain

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Deep Brain Stimulation Aids Resistant Depression

Internal Medicine News ◽

10.1016/s1097-8690(08)71087-4 ◽

2008 ◽

Vol 41 (19) ◽

pp. 20

Author(s):

MICHELE G. SULLIVAN

Keyword(s):

Deep Brain Stimulation ◽

Brain Stimulation ◽

Resistant Depression ◽

Deep Brain

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Nicht-medikamentöse Optionen zur Behandlung pharmakoresistenter Epilepsien

Therapeutische Umschau ◽

10.1024/0040-5930/a001023 ◽

2018 ◽

Vol 75 (7) ◽

pp. 448-454

Author(s):

Thomas Grunwald ◽

Judith Kröll

Keyword(s):

Deep Brain Stimulation ◽

Brain Stimulation ◽

Tiefe Hirnstimulation ◽

Ketogene Diät ◽

Deep Brain

Zusammenfassung. Wenn mit den ersten beiden anfallspräventiven Medikamenten keine Anfallsfreiheit erzielt werden konnte, so ist die Wahrscheinlichkeit, dies mit anderen Medikamenten zu erreichen, nur noch ca. 10 %. Es sollte dann geprüft werden, warum eine Pharmakoresistenz besteht und ob ein epilepsiechirurgischer Eingriff zur Anfallsfreiheit führen kann. Ist eine solche Operation nicht möglich, so können palliative Verfahren wie die Vagus-Nerv-Stimulation (VNS) und die tiefe Hirnstimulation (Deep Brain Stimulation) in eine bessere Anfallskontrolle ermöglichen. Insbesondere bei schweren kindlichen Epilepsien stellt auch die ketogene Diät eine zu erwägende Option dar.

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