scholarly journals Stereotactic electroencephalography with temporal grid and mesial temporal depth electrode coverage: does technique of depth electrode placement affect outcome?

2010 ◽  
Vol 113 (1) ◽  
pp. 32-38 ◽  
Author(s):  
Jamie J. Van Gompel ◽  
Fredric B. Meyer ◽  
W. Richard Marsh ◽  
Kendall H. Lee ◽  
Gregory A. Worrell
Keyword(s):  
Temporal Lobe ◽  
Middle Temporal Gyrus ◽  
Electrode Implantation ◽  
Middle Temporal ◽  
Contact Depth ◽  
Depth Electrodes ◽  
Depth Electrode ◽  
Group A ◽  
Group B ◽  
Seizure Localization

Object Intracranial monitoring for temporal lobe seizure localization to differentiate neocortical from mesial temporal onset seizures requires both neocortical subdural grids and hippocampal depth electrode implantation. There are 2 basic techniques for hippocampal depth electrode implantation. This first technique uses a stereotactically guided 8-contact depth electrode directed along the long axis of the hippocampus to the amygdala via an occipital bur hole. The second technique involves direct placement of 2 or 3 4-contact depth electrodes perpendicular to the temporal lobe through the middle temporal gyrus and overlying subdural grid. The purpose of this study was to determine whether one technique was superior to the other by examining monitoring success and complications. Methods Between 1997 and 2005, 41 patients underwent invasive seizure monitoring with both temporal subdural grids and depth electrodes placed in 2 ways. Patients in Group A underwent the first technique, and patients in Group B underwent the second technique. Results Group A consisted of 26 patients and Group B 15 patients. There were no statistically significant differences between Groups A and B regarding demographics, monitoring duration, seizure localization, or outcome (Engel classification). There was a statistically significant difference at the point in time at which these techniques were used: Group A represented more patients earlier in the series than Group B (p < 0.05). The complication rate attributable to the grids and depth electrodes was 0% in each group. It was more likely that the depth electrodes were placed through the grid if there was a prior resection and the patient was undergoing a new evaluation (p < 0.05). Furthermore, Group A procedures took significantly longer than Group B procedures. Conclusions In this patient series, there was no difference in efficacy of monitoring, complications, or outcome between hippocampal depth electrodes placed laterally through temporal grids or using an occipital bur hole stereotactic approach. Placement of the depth electrodes perpendicularly through the grids and middle temporal gyrus is technically more practical because multiple head positions and redraping are unnecessary, resulting in shorter operative times with comparable results.

scholarly journals Structural Changes Induced by Acupuncture in the Recovering Brain after Ischemic Stroke

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Ping Wu ◽  
Yu-mei Zhou ◽  
Chen-xi Liao ◽  
Yu-zhi Tang ◽  
Yong-xin Li ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Anterior Cingulate Cortex ◽  
Cingulate Cortex ◽  
Anterior Cingulate ◽  
Middle Temporal Gyrus ◽  
Precentral Gyrus ◽  
Stroke Patients ◽  
Middle Temporal ◽  
Group A ◽  
Group B

The aim of this study was to observe the grey matter (GM) tissue changes of ischemic stroke patients, to explore the therapy responses and possible mechanism of acupuncture. 21 stroke patients were randomly assigned to receive either acupuncture plus conventional (Group A) or only conventional (Group B) treatments for 4 weeks. All patients in both groups accepted resting-state functional magnetic resonance (fMRI) scan before and after treatment, and the voxel-based morphometry (VBM) analysis was performed to detect the cerebral grey structure changes. The modified Barthel index (MBI) was used to evaluate the therapeutic effect. Compared with the patients in Group B, the patients in Group A exhibited a more significant enhancement of the changes degree of MBI from pre- to post-treatment intervention. VBM analyses found that after treatment the patients in Group A showed extensive changes in GMV. In Group A, the left frontal lobe, precentral gyrus, superior parietal gyrus, anterior cingulate cortex, and middle temporal gyrus significantly increased, and the right frontal gyrus, inferior parietal gyrus, and middle cingulate cortex decreased (P<0.05, corrected). In addition, left anterior cingulate cortex and left middle temporal gyrus are positively related to the increase in MBI score (P<0.05, corrected). In Group B, right precentral gyrus and right inferior frontal gyrus increased (P<0.05, corrected). In conclusion, acupuncture can evoke pronounced structural reorganization in the frontal areas and the network of DMN areas, which may be the potential therapy target and the potential mechanism where acupuncture improved the motor and cognition recovery.

Robotic Navigated Laser Craniotomy for Depth Electrode Implantation in Epilepsy Surgery: A Cadaver Lab Study

2020 ◽  
Author(s):  
Karl Roessler ◽  
Fabian Winter ◽  
Tobias Wilken ◽  
Ekaterina Pataraia ◽  
Magdalena Mueller-Gerbl ◽  
...  
Keyword(s):  
Laser Beam ◽  
Epilepsy Surgery ◽  
Entry Point ◽  
Occipital Bone ◽  
Electrode Placement ◽  
Target Point ◽  
Twist Drill ◽  
Electrode Implantation ◽  
Depth Electrodes ◽  
Depth Electrode

Abstract Objective Depth electrode implantation for invasive monitoring in epilepsy surgery has become a standard procedure. We describe a new frameless stereotactic intervention using robot-guided laser beam for making precise bone channels for depth electrode placement. Methods A laboratory investigation on a head cadaver specimen was performed using a CT scan planning of depth electrodes in various positions. Precise bone channels were made by a navigated robot-driven laser beam (erbium:yttrium aluminum garnet [Er:YAG], 2.94-μm wavelength,) instead of twist drill holes. Entry point and target point precision was calculated using postimplantation CT scans and comparison to the preoperative trajectory plan. Results Frontal, parietal, and occipital bone channels for bolt implantation were made. The occipital bone channel had an angulation of more than 60 degrees to the surface. Bolts and depth electrodes were implanted solely guided by the trajectory given by the precise bone channels. The mean depth electrode length was 45.5 mm. Entry point deviation was 0.73 mm (±0.66 mm SD) and target point deviation was 2.0 mm (±0.64 mm SD). Bone channel laser time was ∼30 seconds per channel. Altogether, the implantation time was ∼10 to 15 minutes per electrode. Conclusion Navigated robot-assisted laser for making precise bone channels for depth electrode implantation in epilepsy surgery is a promising new, exact and straightforward implantation technique and may have many advantages over twist drill hole implantation.

scholarly journals C.T. Aided Stereotaxy for Depth Electrode Implantation and Biopsy

1983 ◽  
Vol 10 (3) ◽  
pp. 166-169 ◽  
Author(s):  
T.M. Peters ◽  
André Olivier
Keyword(s):  
Computer Program ◽  
Spike Activity ◽  
Three Dimensional ◽  
Modes Of Operation ◽  
Electrode Implantation ◽  
Depth Electrodes ◽  
Depth Electrode ◽  
Epileptic Spike

SUMMARY:We describe a computer program which facilitates the analysis of a series of C.T. scans made while a stereotaxic frame is fixed to the patient.The program has 2 modes of operation:a) The operator may select a region and determine the three-dimensional frame coordinate.b) The operator may select a set of frame coordinates and have the computer program display these at the appropriate sites on the C.T. scans. If these sites are the positions of depth electrodes, then a recording of the epileptic spike activity may be displayed at the appropriate sites on the scans.

Zygomatic Approach for Resection of Mesial Temporal Epileptic Focus

Neurosurgery ◽  
1989 ◽  
Vol 25 (5) ◽  
pp. 798-801 ◽  
Author(s):  
Hiroyuki Shimizu ◽  
Ichiroh Suzuki ◽  
Buichi Ishijima
Keyword(s):  
Temporal Lobe ◽  
Major Part ◽  
Precise Determination ◽  
Middle Temporal Gyrus ◽  
Epileptic Focus ◽  
Middle Temporal ◽  
Combined Use ◽  
Lateral Structures ◽  
Dominant Side

Abstract By using the zygomatic approach, temporal mesial and polar epileptic foci are easily accessible through an incision in the inferior temporal gyrus. In this approach, a major part of the superior and middle temporal gyrus is preserved, and there is no risk of postoperative dysnomia even on the dominant side for speech. Combined use of depth and subdural electrodes is advisable for precise determination of focus distributions throughout the mesial and lateral structures of the temporal lobe. We have applied this approach in 5 patients with satisfactory results.

scholarly journals Both the Middle Temporal Gyrus and the Ventral Anterior Temporal Area Are Crucial for Multimodal Semantic Processing: Distortion-corrected fMRI Evidence for a Double Gradient of Information Convergence in the Temporal Lobes

2012 ◽  
Vol 24 (8) ◽  
pp. 1766-1778 ◽  
Author(s):  
Maya Visser ◽  
Elizabeth Jefferies ◽  
Karl V. Embleton ◽  
Matthew A. Lambon Ralph
Keyword(s):  
Temporal Lobe ◽  
Visual Processing ◽  
Semantic Processing ◽  
Ventral Surface ◽  
Middle Temporal Gyrus ◽  
Temporal Region ◽  
Neural Basis ◽  
Temporal Area ◽  
Middle Temporal ◽  
Principal Axes

Most contemporary theories of semantic memory assume that concepts are formed from the distillation of information arising in distinct sensory and verbal modalities. The neural basis of this distillation or convergence of information was the focus of this study. Specifically, we explored two commonly posed hypotheses: (a) that the human middle temporal gyrus (MTG) provides a crucial semantic interface given the fact that it interposes auditory and visual processing streams and (b) that the anterior temporal region—especially its ventral surface (vATL)—provides a critical region for the multimodal integration of information. By utilizing distortion-corrected fMRI and an established semantic association assessment (commonly used in neuropsychological investigations), we compared the activation patterns observed for both the verbal and nonverbal versions of the same task. The results are consistent with the two hypotheses simultaneously: Both MTG and vATL are activated in common for word and picture semantic processing. Additional planned, ROI analyses show that this result follows from two principal axes of convergence in the temporal lobe: both lateral (toward MTG) and longitudinal (toward the anterior temporal lobe).

scholarly journals Evaluation of Brain Structure Based on Voxel and Surface Morphology in Adults with MRI Negative Temporal Lobe Epilepsy

2022 ◽  
Author(s):  
Fan Yang ◽  
Hanjiaerbieke Kukun ◽  
Wenxiao Jia ◽  
Shuang Ding ◽  
Wei Zhao ◽  
...  
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Gray Matter ◽  
Age Of Onset ◽  
Morphological Changes ◽  
Fusiform Gyrus ◽  
Parahippocampal Gyrus ◽  
Middle Temporal Gyrus ◽  
Control Group ◽  
Middle Temporal

Abstract Background MRI-negative TLE (TLE-N) is a manifestation lacks visible MRI findings yet with detectable electrophysiological changes. In this study, differences of gray matter in drug-controlled MRI negative temporal lobe epilepsy (cTLE-N) and drug-resistant MRI negative temporal lobe epilepsy (rTLE-N) patients were calculated and analyzed by voxel-based morphology (VBM) and surface-based morphology (SBM), to discover the brain structural changes of TLE-N patients. Materials and methods Consecutive resident patients with 30 cTLE-N and 21 rTLE-N were recruited into respective groups, and 30 healthy controls’ structural MRI (sMRI) data collected as a control group. Open-source software based on VBM and SBM was deployed as gray matter volume (GMV) and cortical thickness (CT) analytic tools. Results VBM analysis showed that GMV of bilateral thalamus and right lingual gyrus of cTLE-N group, and left hippocampus, left fusiform gyrus and left thalamus of rTLE-N group were smaller compared to HC group(FDR corrected, P<0.05), while right cerebellum, inferior temporal gyrus, hippocampus, parahippocampal gyrus, amygdala, fusiform gyrus, orbital middle frontal gyrus, and left posterior central gyrus in cTLE-N group, and bilateral cerebellum and middle temporal gyrus, right fusiform gyrus, amygdala, hippocampus, and left middle occipital gyrus of rTLE-N group were greater than HC group(FDR corrected, P<0.05). SBM analysis showed that CT of the left medial orbitofrontal cortex and lateral occipital cortex in cTLE-N group, and thickness of the left medial orbitofrontal, temporal pole, middle temporal gyrus and right anterior superior cingulate cortex in rTLE-N group were thinner, compared to HC group. Correlation analysis showed that GMV and CT of different structures were correlated with age of onset, disease duration, and MoCA score. Conclusion This study utilized two different sMRI analytic tools and discovered several brain morphological changes in TLE-N. These morphological changes were also correlated with clinical variables. Further study may indicate the potential of these findings on the recognition of the TLE-N epilepsy network.

Frame-Based vs Frameless Placement of Intrahippocampal Depth Electrodes in Patients With Refractory Epilepsy: A Comparative in Vivo (Application) Study

Neurosurgery ◽  
2011 ◽  
Vol 68 (4) ◽  
pp. 881-887 ◽  
Author(s):  
Martin Ortler ◽  
Florian Sohm ◽  
Wilhelm Eisner ◽  
Richard Bauer ◽  
Judith Dobesberger ◽  
...  
Keyword(s):  
Refractory Epilepsy ◽  
Electrode Position ◽  
Application Study ◽  
Diagnostic Quality ◽  
Maximal Error ◽  
Depth Electrodes ◽  
Normal Distance ◽  
Group A ◽  
Group B

Abstract BACKGROUND: Despite progress in imaging technologies, documentation of unifocal electrical excitability is pivotal in patient selection for epilepsy surgery. OBJECTIVE: To compare the application accuracy of the Vogele-Bale-Hohner system (VBH), a maxillary fixation system with an external fiducial frame permitting frameless stereotactic guidance, with that of conventional frame-based stereotaxy for placement of intrahippocampal depth electrodes (DEs) in patients with refractory epilepsy. METHODS: Retrospective study. Comparison of two patient cohorts with DEs implanted along the occipitotemporal axis (group A, VBH; group B, frame-based stereotaxy). In vivo accuracy (lateral target localization error [TLE]), determined postoperatively by measuring the normal distance between virtual target and real electrode position at the tip and at 4cm from the tip, number of electrode contacts within the target structure, and diagnostic quality of electroencephalogram recordings were compared. RESULTS: Seventeen DEs (A, 6 electrodes, 60 contacts; B, 11 electrodes, 90 contacts) were placed. electroencephalogram recordings via DEs supported further treatment decisions in all patients. TLE was 2.433 ± 0.977 mm (SD) (95% confidence interval [CI], 1.715-3.214 mm) (A) and 1.803 ± 0.392 mm (SD) (95% CI,1.511-2.195 mm) (B) (P = .185). Maximal error was 4 mm (A) and 3.2 mm (B). TLE 4 cm from the tip was 2.166 ± 2.188 mm (SD) (95% CI,0.438-3.916 mm) (A) and 1.372 ± 0.548 mm (SD) (95% CI,1.049-1.695 mm) (B) (P = .39). Maximal error 4 cm from the tip was 6.4 mm (A) and 2.14 mm (B). On average, 7 (A) and 5 (B) electrode contacts were placed in the target region. CONCLUSION: The VBH and frame-based systems offer similar in vivo accuracy for intrahippocampal DE placement. With frame-based methods, accuracy is higher but the number of contacts per side is lower. This does not translate to clinically important differences.

scholarly journals The role of the irritative zone and of the number and distribution of calcifications in the severity of epilepsy associated with intracranial calcifications

2006 ◽  
Vol 64 (4) ◽  
pp. 905-911 ◽  
Author(s):  
Pedro André Kowacs ◽  
Enio Rogacheski ◽  
Juliano Muzzio ◽  
Lineu César Werneck
Keyword(s):  
Temporal Lobe ◽  
Control Group ◽  
Intracranial Calcifications ◽  
Eeg Abnormalities ◽  
Interictal Eeg ◽  
Group A ◽  
Group B ◽  
Temporal Lobe Seizure ◽  
Patients With Epilepsy

OBJECTIVE: To determine the influence of the location of the irritative zone, and the number and the distribution of the intracranial calcifications in the severity of epilepsy associated with intracranial calcifications. METHOD: We studied 47 patients with epilepsy and intracranial calcifications, 24 with normal (Group A) and 23 with abnormal interictal EEGs (Group B), a control group (n=21) with abnormal interictal EEGs and normal CT-scans (Group C). Clinical, electroencephalographic and neuroradiological features were compared among groups. RESULTS: Temporal lobe interictal EEG abnormalities were found in 23/24 Group B patients, and in all Group C patients. Most Group B and Group C patients presented temporal lobe seizure symptomatology, whereas in most Group A patients symptomatology was rolandic (p=0.0001). Epilepsy was more severe in Group B and Group C patients than in Group A patients (p=0.0001 and p=0.0054). No relationship was found between the number of calcifications and epilepsy severity. CONCLUSION: An irritative zone at the temporal lobe is more relevant in determining the severity, symptomatology and frequency of seizures than the number and location of calcifications.

Sign in / Sign up

Export Citation Format

Share Document