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Alimlouis Benabid - One of the best experts on this subject based on the ideXlab platform.
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Functional Neurosurgery for movement disorders: a historical perspective.
Prog Brain Research, 2009Co-Authors: Alimlouis Benabid, Stephan Chabardès, Napoleon Torres, Brigitte Piallat, Paul Krack, Valérie Fraix, Pierre PollakAbstract:Since the 1960s, deep brain stimulation and spinal cord stimulation at low frequency (30 Hz) have been used to treat intractable pain of various origins. For this purpose, specific hardware have been designed, including deep brain electrodes, extensions, and implantable programmable generators (IPGs). In the meantime, movement disorders, and particularly parkinsonian and essential tremors, were treated by electrolytic or mechanic lesions in various targets of the basal ganglia, particularly in the thalamus and in the internal pallidum. The advent in the 1960s of levodopa, as well as the side effects and complications of ablative surgery (e.g., thalamotomy and pallidotomy), has sent Functional Neurosurgery of movement disorders to oblivion. In 1987, the serendipitous discovery of the effect of high-frequency stimulation (HFS), mimicking lesions, allowed the revival of the surgery of movement disorders by stimulation of the thalamus, which treated tremors with limited morbidity, and adaptable and reversible results. The stability along time of these effects allowed extending it to new targets suggested by basic research in monkeys. The HFS of the subthalamic nucleus (STN) has profoundly challenged the practice of Functional surgery as the effect on the triad of dopaminergic symptoms was very significant, allowing to decrease the drug dosage and therefore a decrease of their complications, the levodopa-induced dyskinesias. In the meantime, based on the results of previous basic research in various fields, HFS has been progressively extended to potentially treat epilepsy and, more recently, psychiatric disorders, such as obsessive-compulsive disorders, Gilles de la Tourette tics, and severe depression. Similarly, suggested by the observation of changes in PET scan, applications have been extended to cluster headaches by stimulation of the posterior hypothalamus and even more recently, to obesity and drug addiction. In the field of movement disorders, it has become clear that STN stimulation is not efficient on the nondopaminergic symptoms such as freezing of gait. Based on experimental data obtained in MPTP-treated parkinsonian monkeys, the pedunculopontine nucleus has been used as a new target, and as suggested by the animal research results, its use indeed improves walking and stability when stimulation is performed at low frequency (25 Hz). The concept of simultaneous stimulation of multiple targets eventually at low or high frequency, and that of several electrodes in one target, is being accepted to increase the efficiency. This leads to and is being facilitated by the development of new hardware (multiple-channel IPGs, specific electrodes, rechargeable batteries). Still additional efforts are needed at the level of the stimulation paradigm and in the waveform. The recent development of nanotechnologies allows the design of totally new systems expanding the field of deep brain stimulation. These new techniques will make it possible to not only inhibit or excite deep brain structures to alleviate abnormal symptoms but also open the field for the use of recording cortical activities to drive neuroprostheses through brain-computer interfaces. The new field of compensation of deficits will then become part of the field of Functional Neurosurgery.
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an algorithm for rapid calculation of a probabilistic Functional atlas of subcortical structures from electrophysiological data collected during Functional Neurosurgery procedures
NeuroImage, 2003Co-Authors: Wieslaw L. Nowinski, Dmitry Belov, Alimlouis BenabidAbstract:The paper introduces an optimal algorithm for rapid calculation of a probabilistic Functional atlas (PFA) of subcortical structures from data collected during Functional Neurosurgery procedures. The PFA is calculated based on combined intraoperative electrophysiology, pre- and intraoperative neuroimaging, and postoperative neurological verification. The algorithm converts the coordinates of the neurologically most effective contacts into probabilistic Functional maps taking into account the geometry of a stimulating electrode. The PFA calculation comprises the reconstruction of the contact coordinates from two orthogonal projections, normalizing (warping) the contacts modeled as cylinders, voxelizing the contact models, calculating the atlas, and computing probability. In addition, an analytical representation of the PFA is formulated based on Gaussian modeling. The initial PFA has been calculated from the data collected during the treatment of 274 Parkinson's disease patients, most of them operated bilaterally (487 operated hemispheres). It contains the most popular stereotactic targets, the subthalamic nucleus, globus pallidus internus, and ventral intermedius nucleus. The key application of the algorithm is targeting in stereotactic and Functional Neurosurgery, and it also can be employed in human and animal brain research.
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a community centric internet portal for stereotactic and Functional Neurosurgery with a probabilistic Functional atlas
Stereotactic and Functional Neurosurgery, 2002Co-Authors: Wieslaw L. Nowinski, Dmitry Belov, Alimlouis BenabidAbstract:Objective: This paper describes an Internet portal for stereotactic and Functional Neurosurgery with a probabilistic Functional atlas (PFA) calculated from electrophysiological and
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MICCAI - The Clinical Use of Multi-modal Resources (2D/3D/Statistics) for Robot Assisted Functional Neurosurgery
Medical Image Computing and Computer-Assisted Intervention – MICCAI 2001, 2001Co-Authors: Alimlouis Benabid, Dominque Hoffmann, Luc Court, Vincent Robert, Sébastien Burtin, Patrick Pittet, Jörg FischerAbstract:This paper presents specific techniques and their implementation to integrate in the planing of Functional Neurosurgery all the available resources (3D preoperative examinations, intra-operative 2D radiographic X-rays, statistical database and atlases).
Ludvic Zrinzo - One of the best experts on this subject based on the ideXlab platform.
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A literature review of magnetic resonance imaging sequence advancements in visualizing Functional Neurosurgery targets.
Journal of neurosurgery, 2021Co-Authors: Alexandre Boutet, Ludvic Zrinzo, Gavin J B Elias, Jürgen Germann, Aaron Loh, Clement T Chow, Alaa Taha, Clemens Neudorfer, Michelle Paff, Alfonso FasanoAbstract:Historically, preoperative planning for Functional Neurosurgery has depended on the indirect localization of target brain structures using visible anatomical landmarks. However, recent technological advances in neuroimaging have permitted marked improvements in MRI-based direct target visualization, allowing for refinement of "first-pass" targeting. The authors reviewed studies relating to direct MRI visualization of the most common Functional Neurosurgery targets (subthalamic nucleus, globus pallidus, and thalamus) and summarize sequence specifications for the various approaches described in this literature. The peer-reviewed literature on MRI visualization of the subthalamic nucleus, globus pallidus, and thalamus was obtained by searching MEDLINE. Publications examining direct MRI visualization of these deep brain stimulation targets were included for review. A variety of specialized sequences and postprocessing methods for enhanced MRI visualization are in current use. These include susceptibility-based techniques such as quantitative susceptibility mapping, which exploit the amount of tissue iron in target structures, and white matter attenuated inversion recovery, which suppresses the signal from white matter to improve the distinction between gray matter nuclei. However, evidence confirming the superiority of these sequences over indirect targeting with respect to clinical outcome is sparse. Future targeting may utilize information about Functional and structural networks, necessitating the use of resting-state Functional MRI and diffusion-weighted imaging. Specialized MRI sequences have enabled considerable improvement in the visualization of common deep brain stimulation targets. With further validation of their ability to improve clinical outcomes and advances in imaging techniques, direct visualization of targets may play an increasingly important role in preoperative planning.
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a literature review of magnetic resonance imaging sequence advancements in visualizing Functional Neurosurgery targets
Journal of Neurosurgery, 2021Co-Authors: Alexandre Boutet, Ludvic Zrinzo, Gavin J B Elias, Jürgen Germann, Aaron Loh, Clement T Chow, Alaa Taha, Clemens Neudorfer, Michelle Paff, Alfonso FasanoAbstract:OBJECTIVE Historically, preoperative planning for Functional Neurosurgery has depended on the indirect localization of target brain structures using visible anatomical landmarks. However, recent technological advances in neuroimaging have permitted marked improvements in MRI-based direct target visualization, allowing for refinement of "first-pass" targeting. The authors reviewed studies relating to direct MRI visualization of the most common Functional Neurosurgery targets (subthalamic nucleus, globus pallidus, and thalamus) and summarize sequence specifications for the various approaches described in this literature. METHODS The peer-reviewed literature on MRI visualization of the subthalamic nucleus, globus pallidus, and thalamus was obtained by searching MEDLINE. Publications examining direct MRI visualization of these deep brain stimulation targets were included for review. RESULTS A variety of specialized sequences and postprocessing methods for enhanced MRI visualization are in current use. These include susceptibility-based techniques such as quantitative susceptibility mapping, which exploit the amount of tissue iron in target structures, and white matter attenuated inversion recovery, which suppresses the signal from white matter to improve the distinction between gray matter nuclei. However, evidence confirming the superiority of these sequences over indirect targeting with respect to clinical outcome is sparse. Future targeting may utilize information about Functional and structural networks, necessitating the use of resting-state Functional MRI and diffusion-weighted imaging. CONCLUSIONS Specialized MRI sequences have enabled considerable improvement in the visualization of common deep brain stimulation targets. With further validation of their ability to improve clinical outcomes and advances in imaging techniques, direct visualization of targets may play an increasingly important role in preoperative planning.
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Neuroimaging Technological Advancements for Targeting in Functional Neurosurgery.
Current neurology and neuroscience reports, 2019Co-Authors: Alexandre Boutet, Andres M Lozano, Ludvic Zrinzo, Robert Gramer, Christopher J. Steele, Gavin J B Elias, Jürgen Germann, Ricardo Maciel, Walter Kucharczyk, Alfonso FasanoAbstract:Ablations and particularly deep brain stimulation (DBS) of a variety of CNS targets are established therapeutic tools for movement disorders. Accurate targeting of the intended structure is crucial for optimal clinical outcomes. However, most targets used in Functional Neurosurgery are sub-optimally visualized on routine MRI. This article reviews recent neuroimaging advancements for targeting in movement disorders. Dedicated MRI sequences can often visualize to some degree anatomical structures commonly targeted during DBS surgery, including at 1.5-T field strengths. Due to recent technological advancements, MR images using ultra-high magnetic field strengths and new acquisition parameters allow for markedly improved visualization of common movement disorder targets. In addition, novel neuroimaging techniques have enabled group-level analysis of DBS patients and delineation of areas associated with clinical benefits. These areas might diverge from the conventionally targeted nuclei and may instead correspond to white matter tracts or hubs of Functional networks. Neuroimaging advancements have enabled improved direct visualization-based targeting as well as optimization and adjustment of conventionally targeted structures.
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Errors of image coregistration may necessitate intraoperative refinement in Functional Neurosurgery.
Journal of neurological surgery. Part A Central European neurosurgery, 2013Co-Authors: Ludvic Zrinzo, Marwan HarizAbstract:Errors of Image Coregistration may Necessitate Intraoperative Refinement in Functional Neurosurgery
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Reducing hemorrhagic complications in Functional Neurosurgery: a large case series and systematic literature review: Clinical article
Journal of neurosurgery, 2011Co-Authors: Ludvic Zrinzo, Thomas Foltynie, Patricia Limousin, Marwan HarizAbstract:Object. Hemorrhagic complications carry by far the highest risk of devastating neurological outcome in Functional Neurosurgery. Literature published over the past 10 years suggests that hemorrhage, although relatively rare, remains a significant problem. Estimating the true incidence of and risk factors for hemorrhage in Functional Neurosurgery is a challenging issue. Methods. The authors analyzed the hemorrhage rate in a consecutive series of 214 patients undergoing imageguided deep brain stimulation (DBS) lead placement without microelectrode recording (MER) and with routine postoperative MR imaging lead verification. They also conducted a systematic review of the literature on stereotactic ablative surgery and DBS over a 10-year period to determine the incidence and risk factors for hemorrhage as a complication of Functional Neurosurgery. Results. The total incidence of hemorrhage in our series of image-guided DBS was 0.9%: asymptomatic in 0.5%, symptomatic in 0.5%, and causing permanent deficit in 0.0% of patients. Weighted means calculated from the litera ture review suggest that the overall incidence of hemorrhage in Functional Neurosurgery is 5.0%, with asymptomatic hemorrhage occurring in 1.9% of patients, symptomatic hemorrhage in 2.1% and hemorrhage resulting in permanent deficit or death in 1.1%. Hypertension and age were the most important patient-related factors associated with an increased risk of hemorrhage. Risk factors related to surgical technique included use of MER, number of MER penetrations, as well as sulcal or ventricular involvement by the trajectory. The incidence of hemorrhage in studies adopting an image-guided and image-verified approach without MER was significantly lower than that reported with other operative techniques (p < 0.001 for total number of hemorrhages, p < 0.001 for asymptomatic hemorrhage, p < 0.004 for symptomatic hemorrhage, and p = 0.001 for hemorrhage leading to permanent deficit; Fisher exact test). Conclusions. Age and a history of hypertension are associated with an increased risk of hemorrhage in Functional Neurosurgery. Surgical factors that increase the risk of hemorrhage include the use of MER and sulcal or ventricular incursion. The meticulous use of neuroimaging—both in planning the trajectory and for target verification—can avoid all of these surgery-related risk factors and appears to carry a significantly lower risk of hemorrhage and associated permanent deficit. (DOI: 10.3171/2011.8.JNS101407)
Andres M Lozano - One of the best experts on this subject based on the ideXlab platform.
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The Evolution of Our Journal Stereotactic and Functional Neurosurgery: From 1938 until Now and Beyond.
Stereotactic and functional neurosurgery, 2020Co-Authors: Andres M LozanoAbstract:This work was supported by the R.R. Tasker Chair in Functional Neurosurgery (A.M. Lozano) at University Health Network, Toronto, ON, Canada.
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Neuroimaging Technological Advancements for Targeting in Functional Neurosurgery.
Current neurology and neuroscience reports, 2019Co-Authors: Alexandre Boutet, Andres M Lozano, Ludvic Zrinzo, Robert Gramer, Christopher J. Steele, Gavin J B Elias, Jürgen Germann, Ricardo Maciel, Walter Kucharczyk, Alfonso FasanoAbstract:Ablations and particularly deep brain stimulation (DBS) of a variety of CNS targets are established therapeutic tools for movement disorders. Accurate targeting of the intended structure is crucial for optimal clinical outcomes. However, most targets used in Functional Neurosurgery are sub-optimally visualized on routine MRI. This article reviews recent neuroimaging advancements for targeting in movement disorders. Dedicated MRI sequences can often visualize to some degree anatomical structures commonly targeted during DBS surgery, including at 1.5-T field strengths. Due to recent technological advancements, MR images using ultra-high magnetic field strengths and new acquisition parameters allow for markedly improved visualization of common movement disorder targets. In addition, novel neuroimaging techniques have enabled group-level analysis of DBS patients and delineation of areas associated with clinical benefits. These areas might diverge from the conventionally targeted nuclei and may instead correspond to white matter tracts or hubs of Functional networks. Neuroimaging advancements have enabled improved direct visualization-based targeting as well as optimization and adjustment of conventionally targeted structures.
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What Have We Learned About Movement Disorders from Functional Neurosurgery
Annual review of neuroscience, 2017Co-Authors: Andres M Lozano, William D. Hutchison, Suneil K. KaliaAbstract:Modern Functional Neurosurgery for movement disorders such as Parkinson's disease, tremor, and dystonia involves the placement of focal lesions or the application of deep brain stimulation (DBS) within circuits that modulate motor function. Precise targeting of these motor structures can be further refined by the use of electrophysiological approaches. In particular, microelectrode recordings enable the delineation of neuroanatomic structures. In the course of these operations, there is an opportunity not only to map basal ganglia structures but also to gain insights into how disturbances in neural activity produce movement disorders. In this review, we aim to highlight what the field has uncovered thus far about movement disorders through DBS. The work to date lays the foundation for future studies that will shed further light on dysFunctional circuits mediating diseases of the nervous system and how we might modulate these circuits therapeutically.
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Some recent trends and further promising directions in Functional Neurosurgery.
Acta neurochirurgica. Supplement, 2013Co-Authors: Travis S. Tierney, Tejas Sankar, Andres M LozanoAbstract:The field of Functional Neurosurgery has developed a number of recent innovative neuromodulatory approaches to treat disease that remains resistant to the best medical therapy. These include novel surgical techniques to intervene in motor and cognitive sequelae of refractory epilepsy, neurodegenerative disease, and certain psychiatric conditions. To a large extent, much of the innovation in our field continues to be driven by a systems-level understanding of the impact of disease on the brain. For example, several groups have exploited findings from neuroimaging work to identify a number of new potential neuromodulatory targets for the treatment of refractory depression. Ongoing discoveries at the cellular and molecular level promise targeted gene or drug delivery aimed at curing disease. Neurosurgeons will certainly remain at the forefront of translating these strategies into practical clinical applications. Several randomized trials are now underway to assess the safety and efficacy of a number of new approaches, and we will continue to acquire better knowledge of optimal patient selection, identification of the most effective neuromodulatory targets, and recognition of adverse effects as these studies progress.
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Measuring impact in stereotactic and Functional Neurosurgery: an analysis of the top 100 most highly cited works and the citation classics in the field.
Stereotactic and functional neurosurgery, 2012Co-Authors: Nir Lipsman, Andres M LozanoAbstract:Background: Functional Neurosurgery is a rapidly expanding field, with an exponentially growing literature. However, as with other fields, it can sometimes be difficult to distinguish between what is incremental and what is transformational. One way of measuring durable impact is examining the number of times a specific piece of scholarship is cited by others in the field. For example, papers that have been cited at least 400 times are designated ‘citation classics’ or works that, by virtue of very high citations, have been deemed of particular importance by researchers working in related disciplines. Methods: We queried a large, web-based scholarly database using 49 pre-selected search terms. The results for each individual query was manually examined for relevance to the Functional Neurosurgery field in order to arrive at the top 100 most highly cited papers as well as the citation classics. Results: The top 100 most cited papers, including 61 citation classics, in the stereotactic and Functional Neurosurgery field can be divided into 7 categories: Functional/anatomic studies, technological innovations, and papers relevant to movement disorders, pain, psychiatry, radiosurgery and epilepsy. Conclusions: We have attempted to ascertain which papers have had, and continue to have, significant impact in our rapidly advancing field. At a minimum, the citation classics in Functional Neurosurgery provide both trainees and seasoned surgeons with a reading list of the ‘must-know’ works in the field – works whose influence have helped shape the direction of Functional Neurosurgery well into the future.
Adam N. Mamelak - One of the best experts on this subject based on the ideXlab platform.
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Minimizing Brain Shift in Stereotactic Functional Neurosurgery. Commentary
Neurosurgery, 2010Co-Authors: Erika A Petersen, Ludvic Zrinzo, Marwan Hariz, Thomas Foltynie, Patricia Limousin, Irene Martinez-torres, Etienne Holl, Robert J. Maciunas, Adam N. MamelakAbstract:BACKGROUND: Stereotactic Functional neurosurgical interventions depend on precise anatomic targeting before lesioning or deep brain stimulation (DBS) electrode placement. OBJECTIVE: To examine the degree of subcortical brain shift observed when adopting an image-guided approach to stereotactic Functional Neurosurgery. METHODS: Coordinates for the anterior and posterior commissural points (AC and PC) were recorded on thin-slice stereotactic magnetic resonance imaging (MRI) scans performed before and immediately after DBS electrode implantation in 136 procedures. The changes in length of AC-PC and in stereotactic coordinates for AC and PC were calculated for each intervention. In patients with Parkinson disease undergoing bilateral subthalamic nucleus (STN) DBS with at least 6 months of follow-up, pre- and postoperative scores of the motor part of the Unified Parkinson's Disease Rating Scale (UPDRS-III) were reviewed. RESULTS: Mean (SD) change in AC-PC length (ΔAC-PC) was 0.6 (0.4) mm. There was no statistically significant difference in ΔAC-PC between groups when examining anatomic target subgroups (P =.95), age subgroups (P=.63), sex (P=.59), and unilateral versus bilateral implantation (P=.15). The mean (SD) vector changes for the commissural points were: -0.1 (0.3) mm in X, -0.4 (0.6) mm in Y, and -0.1 (0.7) mm in Z for the AC; and -0.1 (0.3) mm in X, -0.2 (0.7) mm in Y, and 0.0 (0.7) mm in Z for the PC. There was a negligible correlation between the magnitude of brain shift and percentage improvement in UPDRS-III off-medication in patients undergoing STN DBS for PD (R 2
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minimizing brain shift in stereotactic Functional Neurosurgery commentary
Neurosurgery, 2010Co-Authors: Erika A Petersen, Ludvic Zrinzo, Marwan Hariz, Thomas Foltynie, Patricia Limousin, Etienne Holl, Robert J. Maciunas, Irene Martineztorres, Adam N. MamelakAbstract:BACKGROUND: Stereotactic Functional neurosurgical interventions depend on precise anatomic targeting before lesioning or deep brain stimulation (DBS) electrode placement. OBJECTIVE: To examine the degree of subcortical brain shift observed when adopting an image-guided approach to stereotactic Functional Neurosurgery. METHODS: Coordinates for the anterior and posterior commissural points (AC and PC) were recorded on thin-slice stereotactic magnetic resonance imaging (MRI) scans performed before and immediately after DBS electrode implantation in 136 procedures. The changes in length of AC-PC and in stereotactic coordinates for AC and PC were calculated for each intervention. In patients with Parkinson disease undergoing bilateral subthalamic nucleus (STN) DBS with at least 6 months of follow-up, pre- and postoperative scores of the motor part of the Unified Parkinson's Disease Rating Scale (UPDRS-III) were reviewed. RESULTS: Mean (SD) change in AC-PC length (ΔAC-PC) was 0.6 (0.4) mm. There was no statistically significant difference in ΔAC-PC between groups when examining anatomic target subgroups (P =.95), age subgroups (P=.63), sex (P=.59), and unilateral versus bilateral implantation (P=.15). The mean (SD) vector changes for the commissural points were: -0.1 (0.3) mm in X, -0.4 (0.6) mm in Y, and -0.1 (0.7) mm in Z for the AC; and -0.1 (0.3) mm in X, -0.2 (0.7) mm in Y, and 0.0 (0.7) mm in Z for the PC. There was a negligible correlation between the magnitude of brain shift and percentage improvement in UPDRS-III off-medication in patients undergoing STN DBS for PD (R 2 <0.01). CONCLUSION: Brain shift has long been considered an issue in stereotactic targeting during DBS procedures. However, with the image-guided approach and surgical technique used in this study, subcortical brain shift was extremely limited and did not appear to adversely affect clinical outcome.
Marwan Hariz - One of the best experts on this subject based on the ideXlab platform.
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Psychosurgery in the History of Stereotactic Functional Neurosurgery
Stereotactic and functional neurosurgery, 2020Co-Authors: Lara Rzesnitzek, Marwan Hariz, Joachim K. KraussAbstract:The paper invites to reappraise the role of psychosurgery for and within the development of Functional stereotactic Neurosurgery. It highlights the significant and long-lived role of stereotactic Neurosurgery in the treatment of severe and chronic mental disorders. Stereotactic Neurosurgery developed out of psychosurgery. It was leucotomy for psychiatric disorders and chronic pain that paved the way for stereotactic dorsomedial thalamotomy in these indications and subsequently for stereotactic surgery in epilepsy and movement disorders. Through the 1960s stereotactic psychosurgery continued to progress in silence. Due to the increased applications of stereotactic surgery in psychiatric indications, psychosurgery's renaissance was proclaimed in the early 1970s. At the same time, however, a public fearing mind control started to discredit all Functional Neurosurgery for mental disorders, including stereotactic procedures. In writing its own history, stereotactic Neurosurgery's identity as a neuropsychiatric discipline became subsequently increasingly redefined as principally a sort of "surgical neurology," cut off from its psychiatric origin.
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What Would Dr. James Parkinson Think Today? I. The Role of Functional Neurosurgery for Parkinson's Disease
Movement disorders : official journal of the Movement Disorder Society, 2017Co-Authors: Marwan Hariz, Jose A. ObesoAbstract:What would Dr. James Parkinson think today? : I. The role of Functional Neurosurgery for Parkinson's disease
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Errors of image coregistration may necessitate intraoperative refinement in Functional Neurosurgery.
Journal of neurological surgery. Part A Central European neurosurgery, 2013Co-Authors: Ludvic Zrinzo, Marwan HarizAbstract:Errors of Image Coregistration may Necessitate Intraoperative Refinement in Functional Neurosurgery
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Reducing hemorrhagic complications in Functional Neurosurgery: a large case series and systematic literature review: Clinical article
Journal of neurosurgery, 2011Co-Authors: Ludvic Zrinzo, Thomas Foltynie, Patricia Limousin, Marwan HarizAbstract:Object. Hemorrhagic complications carry by far the highest risk of devastating neurological outcome in Functional Neurosurgery. Literature published over the past 10 years suggests that hemorrhage, although relatively rare, remains a significant problem. Estimating the true incidence of and risk factors for hemorrhage in Functional Neurosurgery is a challenging issue. Methods. The authors analyzed the hemorrhage rate in a consecutive series of 214 patients undergoing imageguided deep brain stimulation (DBS) lead placement without microelectrode recording (MER) and with routine postoperative MR imaging lead verification. They also conducted a systematic review of the literature on stereotactic ablative surgery and DBS over a 10-year period to determine the incidence and risk factors for hemorrhage as a complication of Functional Neurosurgery. Results. The total incidence of hemorrhage in our series of image-guided DBS was 0.9%: asymptomatic in 0.5%, symptomatic in 0.5%, and causing permanent deficit in 0.0% of patients. Weighted means calculated from the litera ture review suggest that the overall incidence of hemorrhage in Functional Neurosurgery is 5.0%, with asymptomatic hemorrhage occurring in 1.9% of patients, symptomatic hemorrhage in 2.1% and hemorrhage resulting in permanent deficit or death in 1.1%. Hypertension and age were the most important patient-related factors associated with an increased risk of hemorrhage. Risk factors related to surgical technique included use of MER, number of MER penetrations, as well as sulcal or ventricular involvement by the trajectory. The incidence of hemorrhage in studies adopting an image-guided and image-verified approach without MER was significantly lower than that reported with other operative techniques (p < 0.001 for total number of hemorrhages, p < 0.001 for asymptomatic hemorrhage, p < 0.004 for symptomatic hemorrhage, and p = 0.001 for hemorrhage leading to permanent deficit; Fisher exact test). Conclusions. Age and a history of hypertension are associated with an increased risk of hemorrhage in Functional Neurosurgery. Surgical factors that increase the risk of hemorrhage include the use of MER and sulcal or ventricular incursion. The meticulous use of neuroimaging—both in planning the trajectory and for target verification—can avoid all of these surgery-related risk factors and appears to carry a significantly lower risk of hemorrhage and associated permanent deficit. (DOI: 10.3171/2011.8.JNS101407)
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Minimizing Brain Shift in Stereotactic Functional Neurosurgery. Commentary
Neurosurgery, 2010Co-Authors: Erika A Petersen, Ludvic Zrinzo, Marwan Hariz, Thomas Foltynie, Patricia Limousin, Irene Martinez-torres, Etienne Holl, Robert J. Maciunas, Adam N. MamelakAbstract:BACKGROUND: Stereotactic Functional neurosurgical interventions depend on precise anatomic targeting before lesioning or deep brain stimulation (DBS) electrode placement. OBJECTIVE: To examine the degree of subcortical brain shift observed when adopting an image-guided approach to stereotactic Functional Neurosurgery. METHODS: Coordinates for the anterior and posterior commissural points (AC and PC) were recorded on thin-slice stereotactic magnetic resonance imaging (MRI) scans performed before and immediately after DBS electrode implantation in 136 procedures. The changes in length of AC-PC and in stereotactic coordinates for AC and PC were calculated for each intervention. In patients with Parkinson disease undergoing bilateral subthalamic nucleus (STN) DBS with at least 6 months of follow-up, pre- and postoperative scores of the motor part of the Unified Parkinson's Disease Rating Scale (UPDRS-III) were reviewed. RESULTS: Mean (SD) change in AC-PC length (ΔAC-PC) was 0.6 (0.4) mm. There was no statistically significant difference in ΔAC-PC between groups when examining anatomic target subgroups (P =.95), age subgroups (P=.63), sex (P=.59), and unilateral versus bilateral implantation (P=.15). The mean (SD) vector changes for the commissural points were: -0.1 (0.3) mm in X, -0.4 (0.6) mm in Y, and -0.1 (0.7) mm in Z for the AC; and -0.1 (0.3) mm in X, -0.2 (0.7) mm in Y, and 0.0 (0.7) mm in Z for the PC. There was a negligible correlation between the magnitude of brain shift and percentage improvement in UPDRS-III off-medication in patients undergoing STN DBS for PD (R 2
