Continuously Decoding Grasping Movements using Stereotactic Depth Electrodes

OBJECTIVESmall lesions at the depth of the sulcus, such as with bottom-of-sulcus focal cortical dysplasia, are not visible from the surface of the brain and can therefore be technically challenging to resect. In this technical note, the authors describe their method of using depth electrodes as landmarks for the subsequent resection of these exacting lesions.METHODSA retrospective review was performed on pediatric patients who had undergone invasive electroencephalography with depth electrodes that were subsequently used as guides for resection in the period between July 2015 and June 2017.RESULTSTen patients (3–15 years old) met the criteria for this study. At the same time as invasive subdural grid and/or strip insertion, between 2 and 4 depth electrodes were placed using a hand-held frameless neuronavigation technique. Of the total 28 depth electrodes inserted, all were found within the targeted locations on postoperative imaging. There was 1 patient in whom an asymptomatic subarachnoid hemorrhage was demonstrated on postprocedural imaging. Depth electrodes aided in target identification in all 10 cases.CONCLUSIONSDepth electrodes placed at the time of invasive intracranial electrode implantation can be used to help localize, target, and resect primary zones of epileptogenesis caused by bottom-of-sulcus lesions.

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Efficient automated localization of ECoG electrodes in CT images via shape analysis

International Journal of Computer Assisted Radiology and Surgery ◽

10.1007/s11548-021-02325-0 ◽

2021 ◽

Vol 16 (4) ◽

pp. 543-554

Author(s):

Jessica Centracchio ◽

Antonio Sarno ◽

Daniele Esposito ◽

Emilio Andreozzi ◽

Luigi Pavone ◽

...

Keyword(s):

Shape Analysis ◽

Focal Epilepsy ◽

Support Vector ◽

Epileptogenic Zone ◽

Platinum Electrodes ◽

Public Repository ◽

Automated Method ◽

Depth Electrodes ◽

Ethical Approval ◽

Cortical Regions

Abstract Purpose People with drug-refractory epilepsy are potential candidates for surgery. In many cases, epileptogenic zone localization requires intracranial investigations, e.g., via ElectroCorticoGraphy (ECoG), which uses subdural electrodes to map eloquent areas of large cortical regions. Precise electrodes localization on cortical surface is mandatory to delineate the seizure onset zone. Simple thresholding operations performed on patients’ computed tomography (CT) volumes recognize electrodes but also other metal objects (e.g., wires, stitches), which need to be manually removed. A new automated method based on shape analysis is proposed, which provides substantially improved performances in ECoG electrodes recognition. Methods The proposed method was retrospectively tested on 24 CT volumes of subjects with drug-refractory focal epilepsy, presenting a large number (> 1700) of round platinum electrodes. After CT volume thresholding, six geometric features of voxel clusters (volume, symmetry axes lengths, circularity and cylinder similarity) were used to recognize the actual electrodes among all metal objects via a Gaussian support vector machine (G-SVM). The proposed method was further tested on seven CT volumes from a public repository. Simultaneous recognition of depth and ECoG electrodes was also investigated on three additional CT volumes, containing penetrating depth electrodes. Results The G-SVM provided a 99.74% mean classification accuracy across all 24 single-patient datasets, as well as on the combined dataset. High accuracies were obtained also on the CT volumes from public repository (98.27% across all patients, 99.68% on combined dataset). An overall accuracy of 99.34% was achieved for the recognition of depth and ECoG electrodes. Conclusions The proposed method accomplishes automated ECoG electrodes localization with unprecedented accuracy and can be easily implemented into existing software for preoperative analysis process. The preliminary yet surprisingly good results achieved for the simultaneous depth and ECoG electrodes recognition are encouraging. Ethical approval n°NCT04479410 by “IRCCS Neuromed” (Pozzilli, Italy), 30th July 2020.

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Depth Electrode Guided Anterior Insulectomy: 2-Dimensional Operative Video

Operative Neurosurgery ◽

10.1093/ons/opab112 ◽

2021 ◽

Author(s):

Mauricio Mandel ◽

Layton Lamsam ◽

Pue Farooque ◽

Dennis Spencer ◽

Eyiyemisi Damisah

Keyword(s):

Right Hemisphere ◽

Preoperative Evaluation ◽

Epileptiform Activity ◽

Neurological Deficits ◽

Depth Electrodes ◽

Depth Electrode ◽

Patient Reported ◽

Frontal Operculum ◽

History Of ◽

Electroencephalogram Eeg

Abstract The insula is well established as an epileptogenic area.1 Insular epilepsy surgery demands precise anatomic knowledge2-4 and tailored removal of the epileptic zone with careful neuromonitoring.5 We present an operative video illustrating an intracranial electroencephalogram (EEG) depth electrode guided anterior insulectomy. We report a 17-yr-old right-handed woman with a 4-yr history of medically refractory epilepsy. The patient reported daily nocturnal ictal vocalization preceded by an indescribable feeling. Preoperative evaluation was suggestive of a right frontal-temporal onset, but the noninvasive results were discordant. She underwent a combined intracranial EEG study with a frontal-parietal grid, with strips and depth electrodes covering the entire right hemisphere. Epileptiform activity was observed in contact 6 of the anterior insula electrode. The patient consented to the procedure and to the publication of her images. A right anterior insulectomy was performed. First, a portion of the frontal operculum was resected and neuronavigation was used for the initial insula localization. However, due to unreliable neuronavigation (ie, brain shift), the medial and anterior borders of the insular resection were guided by the depth electrode reference. The patient was discharged 3 d after surgery with no neurological deficits and remains seizure free. We demonstrate that depth electrode guided insular surgery is a safe and precise technique, leading to an optimal outcome.

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Continuous Intraoperative Neurophysiological Monitoring of the Motor Pathways Using Depth Electrodes During Surgical Resection of an Epileptogenic Lesion: A Novel Technique

Operative Neurosurgery ◽

10.1093/ons/opaa463 ◽

2021 ◽

Author(s):

Denise F Chen ◽

Jon T Willie ◽

David Cabrera ◽

Katie L Bullinger ◽

Ioannis Karakis

Keyword(s):

Motor Cortex ◽

Surgical Resection ◽

Radiation Necrosis ◽

World Health ◽

Intraoperative Neurophysiological Monitoring ◽

Neurophysiological Monitoring ◽

Epileptogenic Zone ◽

Motor Pathways ◽

Depth Electrodes ◽

Epileptogenic Lesion

Abstract BACKGROUND AND IMPORTANCE Intraoperative neurophysiological monitoring of the motor pathways during epilepsy surgery is essential to safely achieve maximal resection of the epileptogenic zone. Motor evoked potential (MEP) recording is usually performed intermittently during resection using a handheld stimulator or continuously through an electrode array placed on the motor cortex. We present a novel variation of continuous MEP acquisition through previously implanted depth electrodes in the perirolandic cortex. CLINICAL PRESENTATION A 60-yr-old woman with a history of a left frontal meningioma (World Health Organization [WHO] grade II) treated with surgical resection and radiation presented with residual right hemiparesis and refractory epilepsy. Imaging demonstrated a perirolandic lesion with surrounding edema and mass effect in the prior surgical site, suspicious for radiation necrosis versus tumor recurrence. Presurgical electrocorticography (ECoG) with orthogonal, stereotactically implanted depth electrodes (stereoelectroencephalography [SEEG]) of the perirolandic cortex captured seizure onsets from the supplementary motor area (SMA) and primary motor cortex (PMC). The patient underwent a left frontal craniotomy for repeat resection and tissue diagnosis. Intraoperative ECoG and MEPs were obtained continuously with direct cortical stimulation through the indwelling SEEG electrodes in the PMC. Maximal resection was achieved with preservation of direct cortical MEPs and without deterioration of her baseline hemiparesis. Biopsy revealed radiation necrosis. At 30-mo follow-up, the patient had only rare seizures (Engel class IIB). CONCLUSION Intraoperative cortical MEP acquisition through implanted SEEG electrode arrays is a potentially safe and effective alternative approach to continuously monitor the motor pathways during the resection of a perirolandic epileptogenic lesion, without the need for surgical interruptions.

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Encoding of speed and direction of movement in the human supplementary motor area

Journal of Neurosurgery ◽

10.3171/2008.10.jns08466 ◽

2009 ◽

Vol 110 (6) ◽

pp. 1304-1316 ◽

Cited By ~ 32

Author(s):

Ariel Tankus ◽

Yehezkel Yeshurun ◽

Tamar Flash ◽

Itzhak Fried

Keyword(s):

Firing Rate ◽

Supplementary Motor Area ◽

Motor Task ◽

Motor Area ◽

Anterior Cingulate ◽

Neuron Activity ◽

Kinematic Parameters ◽

Speed Increase ◽

Hand Motion ◽

Depth Electrodes

Object The supplementary motor area (SMA) plays an important role in planning, initiation, and execution of motor acts. Patients with SMA lesions are impaired in various kinematic parameters, such as velocity and duration of movement. However, the relationships between neuronal activity and these parameters in the human brain have not been fully characterized. This is a study of single-neuron activity during a continuous volitional motor task, with the goal of clarifying these relationships for SMA neurons and other frontal lobe regions in humans. Methods The participants were 7 patients undergoing evaluation for epilepsy surgery requiring implantation of intracranial depth electrodes. Single-unit recordings were conducted while the patients played a computer game involving movement of a cursor in a simple maze. Results In the SMA proper, most of the recorded units exhibited a monotonic relationship between the unit firing rate and hand motion speed. The vast majority of SMA proper units with this property showed an inverse relation, that is, firing rate decrease with speed increase. In addition, most of the SMA proper units were selective to the direction of hand motion. These relationships were far less frequent in the pre-SMA, anterior cingulate gyrus, and orbitofrontal cortex. Conclusions The findings suggest that the SMA proper takes part in the control of kinematic parameters of endeffector motion, and thus lend support to the idea of connecting neuroprosthetic devices to the human SMA.

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The Neural Basis of Aggression and its Treatment by Psychosurgery

Australian & New Zealand Journal of Psychiatry ◽

10.3109/00048677809159584 ◽

1978 ◽

Vol 12 (1) ◽

pp. 21-28 ◽

Cited By ~ 6

Author(s):

L. G. Kiloh ◽

J. S. Smith

Keyword(s):

Informed Consent ◽

Limbic System ◽

Aggressive Behaviour ◽

Surgical Techniques ◽

Neural Basis ◽

Violent Behaviour ◽

Epileptiform Discharges ◽

Depth Electrodes

The limbic system and its connections provide the neural basis for aggressive behaviour. Violent individuals may differ quantitively or qualitively from normal. Many of the latter suffer from epilepsy. In some the epileptiform discharges from the amygdala can only be recorded using depth electrodes. It can be taken that the control of abnormal degrees of violent behaviour is now possible. Should such operations be used? If so who should have them? What precautions need to be taken that such operations are not abused? How can informed consent be obtained? The development of new surgical techniques make these questions pertinent if not urgent.

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Locally Applied Valproate Enhances Survival in Rats after Neocortical Treatment with Tetanus Toxin and Cobalt Chloride

BioMed Research International ◽

10.1155/2013/497485 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Dirk-Matthias Altenmüller ◽

Jonas M. Hebel ◽

Michael P. Rassner ◽

Silvanie Volz ◽

Thomas M. Freiman ◽

...

Keyword(s):

Tetanus Toxin ◽

Cobalt Chloride ◽

Local Application ◽

Controlled Study ◽

Epileptic Focus ◽

Depth Electrodes ◽

Spontaneous Seizures ◽

Neocortical Epilepsy ◽

The Right ◽

Therapy Strategies

Purpose. In neocortical epilepsies not satisfactorily responsive to systemic antiepileptic drug therapy, local application of antiepileptic agents onto the epileptic focus may enhance treatment efficacy and tolerability. We describe the effects of focally applied valproate (VPA) in a newly emerging rat model of neocortical epilepsy induced by tetanus toxin (TeT) plus cobalt chloride (CoCl2).Methods. In rats, VPA (n=5) or sodium chloride (NaCl) (n=5) containing polycaprolactone (PCL) implants were applied onto the right motor cortex treated before with a triple injection of 75 ng TeT plus 15 mg CoCl2. Video-EEG monitoring was performed with intracortical depth electrodes.Results. All rats randomized to the NaCl group died within one week after surgery. In contrast, the rats treated with local VPA survived significantly longer (P<0.01). In both groups, witnessed deaths occurred in the context of seizures. At least3/4of the rats surviving the first postoperative day developed neocortical epilepsy with recurrent spontaneous seizures.Conclusions. The novel TeT/CoCl2approach targets at a new model of neocortical epilepsy in rats and allows the investigation of local epilepsy therapy strategies. In this vehicle-controlled study, local application of VPA significantly enhanced survival in rats, possibly by focal antiepileptic or antiepileptogenic mechanisms.

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Endoscopic Transcortical Selective Amygdalohippocampectomy for Mesial Temporal Lobe Epilepsy: 2-Dimensional Operative Video

Operative Neurosurgery ◽

10.1093/ons/opab265 ◽

2021 ◽

Author(s):

Takehiro Uda ◽

Toshiyuki Kawashima ◽

Masato Hattori ◽

Yuichiro Kojima ◽

Yuki Mito ◽

...

Keyword(s):

Hippocampal Sclerosis ◽

Mesial Temporal Lobe Epilepsy ◽

Skin Incision ◽

Cognitive Outcomes ◽

Parahippocampal Gyrus ◽

Middle Temporal Gyrus ◽

Surgical Video ◽

Selective Amygdalohippocampectomy ◽

Depth Electrodes ◽

The Right

Abstract This surgical video shows a 19-yr-old woman with focal impaired awareness seizures. Seizure semiology showed no lateralizing signs. Ictal electroencephalography (EEG) failed to determine the seizure origin. Interictal EEG showed bilateral spike-and-waves at the temporal electrodes. Magnetic resonance imaging (MRI) showed suspected hippocampal sclerosis on the right side. To determine the side of the focus, depth electrodes were implanted in both hippocampi. Invasive video EEG identified the seizure origin on the right. The decision was made to perform selective amygdalohippocampectomy (SelAH) via the middle temporal gyrus (MTG). An endoscope was used to minimize the craniotomy and shorten the skin incision. A 5-cm linear skin incision and 2.5-cm craniotomy were made. A thin tube was inserted to the inferior horn of the lateral ventricle (Inf-H) under neuronavigation to guide the route to the Inf-H. The endoscope was introduced. A 1.5-cm corticotomy was made at the MTG, and white matter was aspirated until opening the Inf-H. The hippocampus and parahippocampal gyrus were removed with the usual steps in microsurgical SelAH. The surgical time was 4 h 20 min. The patient was discharged without complications and has remained seizure free. In addition to the preoperative objectives, using an endoscope widens the surgical view in the Inf-H compared with microsurgical procedures. Although seizure and cognitive outcomes are expected to be comparable to those from other methods of SelAH, invasiveness might be reduced. This appears to represent the first video report of endoscopic SelAH. The patient consented to the procedure and publication of her images and surgical video.

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