scholarly journals Network Substrates of Centromedian Nucleus Deep Brain Stimulation in Generalized Pharmacoresistant Epilepsy

2021 ◽  
Author(s):  
Cristina V. Torres Diaz ◽  
Gabriel González-Escamilla ◽  
Dumitru Ciolac ◽  
Marta Navas García ◽  
Paloma Pulido Rivas ◽  
...  

AbstractDeep brain stimulation (DBS), specifically thalamic DBS, has achieved promising results to reduce seizure severity and frequency in pharmacoresistant epilepsies, thereby establishing it for clinical use. The mechanisms of action are, however, still unknown. We evidenced the brain networks directly modulated by centromedian (CM) nucleus-DBS and responsible for clinical outcomes in a cohort of patients uniquely diagnosed with generalized pharmacoresistant epilepsy. Preoperative imaging and long-term (2–11 years) clinical data from ten generalized pharmacoresistant epilepsy patients (mean age at surgery = 30.8 ± 5.9 years, 4 female) were evaluated. Volume of tissue activated (VTA) was included as seeds to reconstruct the targeted network to thalamic DBS from diffusion and functional imaging data. CM-DBS clinical outcome improvement (> 50%) appeared in 80% of patients and was tightly related to VTAs interconnected with a reticular system network encompassing sensorimotor and supplementary motor cortices, together with cerebellum/brainstem. Despite methodological differences, both structural and functional connectomes revealed the same targeted network. Our results demonstrate that CM-DBS outcome in generalized pharmacoresistant epilepsy is highly dependent on the individual connectivity profile, involving the cerebello-thalamo-cortical circuits. The proposed framework could be implemented in future studies to refine stereotactic implantation or the parameters for individualized neuromodulation.

2018 ◽  
Vol 45 (2) ◽  
pp. E5 ◽  
Author(s):  
James J. Zhou ◽  
Tsinsue Chen ◽  
S. Harrison Farber ◽  
Andrew G. Shetter ◽  
Francisco A. Ponce

OBJECTIVEThe field of deep brain stimulation (DBS) for epilepsy has grown tremendously since its inception in the 1970s and 1980s. The goal of this review is to identify and evaluate all studies published on the topic of open-loop DBS for epilepsy over the past decade (2008 to present).METHODSA PubMed search was conducted to identify all articles reporting clinical outcomes of open-loop DBS for the treatment of epilepsy published since January 1, 2008. The following composite search terms were used: (“epilepsy” [MeSH] OR “seizures” [MeSH] OR “kindling, neurologic” [MeSH] OR epilep* OR seizure* OR convuls*) AND (“deep brain stimulation” [MeSH] OR “deep brain stimulation” OR “DBS”) OR (“electric stimulation therapy” [MeSH] OR “electric stimulation therapy” OR “implantable neurostimulators” [MeSH]).RESULTSThe authors identified 41 studies that met the criteria for inclusion. The anterior nucleus of the thalamus, centromedian nucleus of the thalamus, and hippocampus were the most frequently evaluated targets. Among the 41 articles, 19 reported on stimulation of the anterior nucleus of the thalamus, 6 evaluated stimulation of the centromedian nucleus of the thalamus, and 9 evaluated stimulation of the hippocampus. The remaining 7 articles reported on the evaluation of alternative DBS targets, including the posterior hypothalamus, subthalamic nucleus, ventral intermediate nucleus of the thalamus, nucleus accumbens, caudal zone incerta, mammillothalamic tract, and fornix. The authors evaluated each study for overall epilepsy response rates as well as adverse events and other significant, nonepilepsy outcomes.CONCLUSIONSLevel I evidence supports the safety and efficacy of stimulating the anterior nucleus of the thalamus and the hippocampus for the treatment of medically refractory epilepsy. Level III and IV evidence supports stimulation of other targets for epilepsy. Ongoing research into the efficacy, adverse effects, and mechanisms of open-loop DBS continues to expand the knowledge supporting the use of these treatment modalities in patients with refractory epilepsy.


2018 ◽  
Author(s):  
Andreas Horn ◽  
Ningfei Li ◽  
Till A Dembek ◽  
Ari Kappel ◽  
Chadwick Boulay ◽  
...  

AbstractDeep brain stimulation (DBS) is a highly efficacious treatment option for movement disorders and a growing number of other indications are investigated in clinical trials. To ensure optimal treatment outcome, exact electrode placement is required. Moreover, to analyze the relationship between electrode location and clinical results, a precise reconstruction of electrode placement is required, posing specific challenges to the field of neuroimaging. Since 2014 the open source toolbox Lead-DBS is available, which aims at facilitating this process. The tool has since become a popular platform for DBS imaging. With support of a broad community of researchers worldwide, methods have been continuously updated and complemented by new tools for tasks such as multispectral nonlinear registration, structural / functional connectivity analyses, brain shift correction, reconstruction of microelectrode recordings and orientation detection of segmented DBS leads. The rapid development and emergence of these methods in DBS data analysis require us to revisit and revise the pipelines introduced in the original methods publication. Here we demonstrate the updated DBS and connectome pipelines of Lead-DBS using a single patient example with state-of-the-art high-field imaging as well as a retrospective cohort of patients scanned in a typical clinical setting at 1.5T. Imaging data of the 3T example patient is co-registered using five algorithms and nonlinearly warped into template space using ten approaches for comparative purposes. After reconstruction of DBS electrodes (which is possible using three methods and a specific refinement tool), the volume of tissue activated is calculated for two DBS settings using four distinct models and various parameters. Finally, four whole-brain tractography algorithms are applied to the patient’s preoperative diffusion MRI data and structural as well as functional connectivity between the stimulation volume and other brain areas are estimated using a total of eight approaches and datasets. In addition, we demonstrate impact of selected preprocessing strategies on the retrospective sample of 51 PD patients. We compare the amount of variance in clinical improvement that can be explained by the computer model depending on the method of choice.This work represents a multi-institutional collaborative effort to develop a comprehensive, open source pipeline for DBS imaging and connectomics, which has already empowered several studies, and may facilitate a variety of future studies in the field.


2022 ◽  
Vol 12 (1) ◽  
pp. 86
Author(s):  
Mevlüt Yalaz ◽  
Nicholas Maling ◽  
Günther Deuschl ◽  
León M. Juárez-Paz ◽  
Markus Butz ◽  
...  

Background: Current approaches to detect the positions and orientations of directional deep-brain stimulation (DBS) electrodes rely on radiative imaging data. In this study, we aim to present an improved version of a radiation-free method for magnetic detection of the position and the orientation (MaDoPO) of directional electrodes based on a series of magnetoencephalography (MEG) measurements and a possible future solution for optimized results using emerging on-scalp MEG systems. Methods: A directional DBS system was positioned into a realistic head–torso phantom and placed in the MEG scanner. A total of 24 measurements of 180 s each were performed with different predefined electrode configurations. Finite element modeling and model fitting were used to determine the position and orientation of the electrode in the phantom. Related measurements were fitted simultaneously, constraining solutions to the a priori known geometry of the electrode. Results were compared with the results of the high-quality CT imaging of the phantom. Results: The accuracy in electrode localization and orientation detection depended on the number of combined measurements. The localization error was minimized to 2.02 mm by considering six measurements with different non-directional bipolar electrode configurations. Another six measurements with directional bipolar stimulations minimized the orientation error to 4°. These values are mainly limited due to the spatial resolution of the MEG. Moreover, accuracies were investigated as a function of measurement time, number of sensors, and measurement direction of the sensors in order to define an optimized MEG device for this application. Conclusion: Although MEG introduces inaccuracies in the detection of the position and orientation of the electrode, these can be accepted when evaluating the benefits of a radiation-free method. Inaccuracies can be further reduced by the use of on-scalp MEG sensor arrays, which may find their way into clinics in the foreseeable future.


Author(s):  
Sandra Machado

Deep brain stimulation (DBS) is now a widely accepted treatment option for patients with movement disorders such as parkinsonism and essential tremor. DBS surgery presents challenges to the anesthesiologist as often these patients are required to be awake for accurate placement of the stimulators. Additionally, patients with movement disorders often have comorbidities that increase their risk of perioperative and postoperative complications. DBS surgery is often divided into two stages (1) stereotactic implantation of the DBS leads and (2) internalization of the pulse generator, with each of these stages stage having distinct anesthesia demands. Ongoing studies are exploring other indications for the effective use of DBS surgery.


Cephalalgia ◽  
2008 ◽  
Vol 28 (7) ◽  
pp. 799-803 ◽  
Author(s):  
A May

Recently, functional imaging data have underscored the crucial role of the hypothalamus in trigemino-autonomic headaches, a group of severe primary headaches. This prompted the application of hypothalamic deep-brain stimulation (DBS), with the intention to preventing cluster headache (CH) attacks in selected severe therapy-refractory cases. To date, a total of 50 operated intractable CH patients, one patient with short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing and three with atypical facial pain, have been reported. However, it is not apparent why the spontaneous bursts of activation in the inferior posterior hypothalamus result in excruciating head pain, whereas continuous electrical stimulation of the identical area is able to prevent these attacks. Recently, this issue has been addressed by examining 10 operated chronic CH patients, using H215O-positron emission tomography and alternately switching the hypothalamic stimulator on and off. The stimulation-induced activation in the ipsilateral posterior inferior hypothalamic grey (the site of the stimulator tip) as well as activation and de-activation in several cerebral structures belonging to neuronal circuits usually activated in pain transmission. These data argue against an unspecific antinociceptive effect or pure inhibition of hypothalamic activity as the mode of action of hypothalamic DBS and suggest functional modulation of the pain-processing network.


2017 ◽  
Vol 27 (07) ◽  
pp. 1750010 ◽  
Author(s):  
David Martín-López ◽  
Diego Jiménez-Jiménez ◽  
Lidia Cabañés-Martínez ◽  
Richard P. Selway ◽  
Antonio Valentín ◽  
...  

Background: The onset of generalized seizures is a long debated subject in epilepsy. The relative roles of cortex and thalamus in initiating and maintaining the different seizure types are unclear. Objective: The purpose of the study is to estimate whether the cortex or the centromedian thalamic nucleus is leading in initiating and maintaining seizures in humans. Methods: We report human ictal recordings with simultaneous thalamic and cortical electrodes from three patients without anesthesia being assessed for deep brain stimulation (DBS). Patients 1 and 2 had idiopathic generalized epilepsy whereas patient 3 had frontal lobe epilepsy. Visual inspection was combined with nonlinear correlation analysis. Results: In patient 1, seizure onset was bilateral cortical and the belated onset of leading thalamic discharges was associated with an increase in rhythmicity of discharges, both in thalamus and cortex. In patient 2, we observed bilateral independent interictal discharges restricted to the thalamus. However, ictal onset was diffuse, with discharges larger in the cortex even though they were led by the thalamus. In patient 3, seizure onset was largely restricted to frontal structures, with belated lagging thalamic involvement. Conclusion: In human generalized seizures, the thalamus may become involved early or late in the seizure but, once it becomes involved, it leads the cortex. In contrast, in human frontal seizures the thalamus gets involved late in the seizure and, once it becomes involved, it lags behind the cortex. In addition, the centromedian nucleus of the thalamus is capable of autonomous epileptogenesis as suggested by the presence of independent focal unilateral epileptiform discharges restricted to thalamic structures. The thalamus may also be responsible for maintaining the rhythmicity of ictal discharges.


2021 ◽  
Vol 11 (1) ◽  
pp. 87
Author(s):  
Petra Heiden ◽  
Mauritius Hoevels ◽  
Dilruba Bayram ◽  
Juan C. Baldermann ◽  
Thomas Schüller ◽  
...  

Since 1999, several targets for deep brain stimulation (DBS) in Gilles de la Tourette syndrome (GTS) have emerged showing similar success rates. Studies using different tractography techniques have identified connectivity profiles associated with a better outcome for individual targets. However, GTS patients might need individualized therapy. The objective of this study is to analyze the connectivity profile of different DBS targets for GTS. We identified standard target coordinates for the centromedian nucleus/nucleus ventro-oralis internus (CM/Voi), the CM/parafascicular (CM-Pf) complex, the anteromedial globus pallidus internus (amGPi), the posteroventral GPi (pvGPi), the ventral anterior/ventrolateral thalamus (VA/VL), and the nucleus accumbens/anterior limb of the internal capsule (Nacc/ALIC). Probabilistic tractography was performed from the targets to different limbic and motor areas based on patient-specific imaging and a normative connectome (HCP). Our analysis showed significant differences between the connectivity profiles of standard DBS targets (p < 0.05). Among all targets, the pvGPi showed the strongest connection to the sensorimotor cortex, while the amGPi showed the strongest connection to the prefrontal cortex in patient-specific imaging. Differences were observed between the connectivity profiles when using probabilistic tractography based on patient data and HCP. Our findings showed that the connectivity profiles of different DBS targets to major motor and limbic areas differ significantly. In the future, these differences may be considered when planning DBS for GTS patients employing an individualized approach. There were compelling differences in connectivity profiles when using different tractography techniques.


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