Stereoelectroencephalography

Abstract BACKGROUND: Stereoelectroencephalography (SEEG) methodology, originally developed by Talairach and Bancaud, is progressively gaining popularity for the presurgical invasive evaluation of drug-resistant epilepsies. OBJECTIVE: To describe recent SEEG methodological implementations carried out in our center, to evaluate safety, and to analyze in vivo application accuracy in a consecutive series of 500 procedures with a total of 6496 implanted electrodes. METHODS: Four hundred nineteen procedures were performed with the traditional 2-step surgical workflow, which was modified for the subsequent 81 procedures. The new workflow entailed acquisition of brain 3-dimensional angiography and magnetic resonance imaging in frameless and markerless conditions, advanced multimodal planning, and robot-assisted implantation. Quantitative analysis for in vivo entry point and target point localization error was performed on a sub-data set of 118 procedures (1567 electrodes). RESULTS: The methodology allowed successful implantation in all cases. Major complication rate was 12 of 500 (2.4%), including 1 death for indirect morbidity. Median entry point localization error was 1.43 mm (interquartile range, 0.91-2.21 mm) with the traditional workflow and 0.78 mm (interquartile range, 0.49-1.08 mm) with the new one (P < 2.2 × 10−16). Median target point localization errors were 2.69 mm (interquartile range, 1.89-3.67 mm) and 1.77 mm (interquartile range, 1.25-2.51 mm; P < 2.2 × 10−16), respectively. CONCLUSION: SEEG is a safe and accurate procedure for the invasive assessment of the epileptogenic zone. Traditional Talairach methodology, implemented by multimodal planning and robot-assisted surgery, allows direct electrical recording from superficial and deep-seated brain structures, providing essential information in the most complex cases of drug-resistant epilepsy.

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Technique, Results, and Complications Related to Robot-Assisted Stereoelectroencephalography

Neurosurgery ◽

10.1227/neu.0000000000001034 ◽

2015 ◽

Vol 78 (2) ◽

pp. 169-180 ◽

Cited By ~ 121

Author(s):

Jorge González-Martínez ◽

Juan Bulacio ◽

Susan Thompson ◽

John Gale ◽

Saksith Smithason ◽

...

Keyword(s):

Focal Epilepsy ◽

Interquartile Range ◽

Implantation Technique ◽

Target Point ◽

Seizure Outcome ◽

Seizure Freedom ◽

Epileptogenic Zone ◽

Robot Assisted ◽

Depth Electrodes

ABSTRACT BACKGROUND: Robot-assisted stereoelectroencephalography (SEEG) may represent a simplified, precise, and safe alternative to the more traditional SEEG techniques. OBJECTIVE: To report our clinical experience with robotic SEEG implantation and to define its utility in the management of patients with medically refractory epilepsy. METHODS: The prospective observational analyses included all patients with medically refractory focal epilepsy who underwent robot-assisted stereotactic placement of depth electrodes for extraoperative brain monitoring between November 2009 and May 2013. Technical nuances of the robotic implantation technique are presented, as well as an analysis of demographics, time of planning and procedure, seizure outcome, in vivo accuracy, and procedure-related complications. RESULTS: One hundred patients underwent 101 robot-assisted SEEG procedures. Their mean age was 33.2 years. In total, 1245 depth electrodes were implanted. On average, 12.5 electrodes were implanted per patient. The time of implantation planning was 30 minutes on average (range, 15-60 minutes). The average operative time was 130 minutes (range, 45-160 minutes). In vivo accuracy (calculated in 500 trajectories) demonstrated a median entry point error of 1.2 mm (interquartile range, 0.78-1.83 mm) and a median target point error of 1.7 mm (interquartile range, 1.20-2.30 mm). Of the group of patients who underwent resective surgery (68 patients), 45 (66.2%) gained seizure freedom status. Mean follow-up was 18 months. The total complication rate was 4%. CONCLUSION: The robotic SEEG technique and method were demonstrated to be safe, accurate, and efficient in anatomically defining the epileptogenic zone and subsequently promoting sustained seizure freedom status in patients with difficult-to-localize seizures.

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Accuracy of robot-assisted versus optical frameless navigated stereoelectroencephalography electrode placement in children

Journal of Neurosurgery Pediatrics ◽

10.3171/2018.10.peds18227 ◽

2019 ◽

Vol 23 (3) ◽

pp. 297-302 ◽

Cited By ~ 11

Author(s):

Julia D. Sharma ◽

Kiran K. Seunarine ◽

Muhammad Zubair Tahir ◽

Martin M. Tisdall

Keyword(s):

Soft Tissue ◽

Entry Point ◽

Electrode Placement ◽

Target Point ◽

Localization Error ◽

Bone Thickness ◽

Tissue Thickness ◽

Robot Assisted ◽

Soft Tissue Thickness ◽

Safety Margins

OBJECTIVEThe aim of this study was to compare the accuracy of optical frameless neuronavigation (ON) and robot-assisted (RA) stereoelectroencephalography (SEEG) electrode placement in children, and to identify factors that might increase the risk of misplacement.METHODSThe authors undertook a retrospective review of all children who underwent SEEG at their institution. Twenty children were identified who underwent stereotactic placement of a total of 218 electrodes. Six procedures were performed using ON and 14 were placed using a robotic assistant. Placement error was calculated at cortical entry and at the target by calculating the Euclidean distance between the electrode and the planned cortical entry and target points. The Mann-Whitney U-test was used to compare the results for ON and RA placement accuracy. For each electrode placed using robotic assistance, extracranial soft-tissue thickness, bone thickness, and intracranial length were measured. Entry angle of electrode to bone was calculated using stereotactic coordinates. A stepwise linear regression model was used to test for variables that significantly influenced placement error.RESULTSBetween 8 and 17 electrodes (median 10 electrodes) were placed per patient. Median target point localization error was 4.5 mm (interquartile range [IQR] 2.8–6.1 mm) for ON and 1.07 mm (IQR 0.71–1.59) for RA placement. Median entry point localization error was 5.5 mm (IQR 4.0–6.4) for ON and 0.71 mm (IQR 0.47–1.03) for RA placement. The difference in accuracy between Stealth-guided (ON) and RA placement was highly significant for both cortical entry point and target (p < 0.0001 for both). Increased soft-tissue thickness and intracranial length reduced accuracy at the target. Increased soft-tissue thickness, bone thickness, and younger age reduced accuracy at entry. There were no complications.CONCLUSIONSRA stereotactic electrode placement is highly accurate and is significantly more accurate than ON. Larger safety margins away from vascular structures should be used when placing deep electrodes in young children and for trajectories that pass through thicker soft tissues such as the temporal region.

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Stereoencephalography Electrode Placement Accuracy and Utility Using a Frameless Insertion Platform Without a Rigid Cannula

Operative Neurosurgery ◽

10.1093/ons/opz200 ◽

2019 ◽

Author(s):

Erin D’Agostino ◽

John Kanter ◽

Yinchen Song ◽

Joshua P Aronson

Keyword(s):

Electrode Placement ◽

Target Point ◽

Localization Error ◽

Drug Resistant ◽

Guide Cannula ◽

Lateral Entry ◽

Accurate Localization ◽

Depth Electrodes ◽

Rigid Frame ◽

Drug Resistant Epilepsy

Abstract BACKGROUND Implantation of depth electrodes to localize epileptogenic foci in patients with drug-resistant epilepsy can be accomplished using traditional rigid frame-based, custom frameless, and robotic stereotactic systems. OBJECTIVE To evaluate the accuracy of electrode implantation using the FHC microTargeting platform, a custom frameless platform, without a rigid insertion cannula. METHODS A total of 182 depth electrodes were implanted in 13 consecutive patients who underwent stereoelectroencephalography (SEEG) for drug-resistant epilepsy using the microTargeting platform and depth electrodes without a rigid guide cannula. MATLAB was utilized to evaluate targeting accuracy. Three manual coordinate measurements with high inter-rater reliability were averaged. RESULTS Patients were predominantly male (77%) with average age 35.62 (SD 11.0, range 21-57) and average age of epilepsy onset at 13.4 (SD 7.2, range 3-26). A mean of 14 electrodes were implanted (range 10-18). Mean operative time was 144 min (range 104-176). Implantation of 3 out of 182 electrodes resulted in nonoperative hemorrhage (2 small subdural hematomas and one small subarachnoid hemorrhage). Putative location of onset was identified in all patients. We demonstrated a median lateral target point localization error (LTPLE) of 3.95 mm (IQR 2.18-6.23), a lateral entry point localization error (LEPLE) of 1.98 mm (IQR 1.2-2.85), a target depth error of 1.71 mm (IQR 1.03-2.33), and total target point localization error (TPLE) of 4.95 mm (IQR 2.98-6.85). CONCLUSION Utilization of the FHC microTargeting platform without the use of insertion cannulae is safe, effective, and accurate. Localization of seizure foci was accomplished in all patients and accuracy of depth electrode placement was satisfactory.

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Accuracy and Safety of Customized Stereotactic Fixtures for Stereoelectroencephalography in Pediatric Patients

Stereotactic and Functional Neurosurgery ◽

10.1159/000510063 ◽

2020 ◽

pp. 1-8

Author(s):

Constantin Pistol ◽

Andrei Daneasa ◽

Jean Ciurea ◽

Alin Rasina ◽

Andrei Barborica ◽

...

Keyword(s):

Focal Epilepsy ◽

Perioperative Complications ◽

Intractable Epilepsy ◽

Target Point ◽

Seizure Freedom ◽

Epileptogenic Zone ◽

Localization Error ◽

Temporal Area ◽

Lateral Entry ◽

Stereotactic Implantation

Stereoelectroencephalography (SEEG) in children with intractable epilepsy presents particular challenges. Their thin and partially ossified cranium, specifically in the temporal area, is prone to fracture while attaching stereotactic systems to the head or stabilizing the head in robot’s field of action. Postponing SEEG in this special population of patients can have serious consequences, reducing their chances of becoming seizure-free and impacting their social and cognitive development. This study demonstrates the safety and accuracy offered by a frameless personalized 3D printed stereotactic implantation system for SEEG investigations in children under 4 years of age. SEEG was carried out in a 3-year-old patient with drug-resistant focal epilepsy, based on a right temporal-perisylvian epileptogenic zone hypothesis. Fifteen intracerebral electrodes were placed using a StarFix patient-customized stereotactic fixture. The median lateral entry point localization error of the electrodes was 0.90 mm, median lateral target point localization error was 1.86 mm, median target depth error was 0.83 mm, and median target point localization error was 1.96 mm. There were no perioperative complications. SEEG data led to a tailored right temporal-insular-opercular resection, with resulting seizure freedom (Engel IA). In conclusion, patient-customized stereotactic fixtures are a safe and accurate option for SEEG exploration in young children.

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Accuracy of SEEG Electrodes Implanted in Lateral Position Versus Supine Position

Neurosurgery ◽

10.1093/neuros/nyz310_427 ◽

2019 ◽

Vol 66 (Supplement_1) ◽

Author(s):

Caio M Matias ◽

Sandeep Kandregula ◽

Chengyuan Wu ◽

Ashwini D Sharan

Keyword(s):

Supine Position ◽

Three Dimensional ◽

Major Complication ◽

Lateral Position ◽

Entry Point ◽

Target Point ◽

Robot Assisted ◽

Dimensional Error ◽

Electrode Implantation ◽

Position Group

Abstract INTRODUCTION Accuracy during SEEG implantations is critical as several electrodes will cross narrow corridors between cerebral blood vessels. Previous studies have compared the accuracy of different techniques such as frame-based, frameless, and robot-assisted implantations and overall SEEG has been reported to be quite safe, with a major complication incidence of less than 1%. Typically, the supine position is utilized for implantation; however, the lateral position may be more comfortable and ergonomic for trajectories with a posterior entry point (eg, posterior approach to the insula). To our knowledge, this is the first study to compare the accuracy of SEEG electrodes implanted in supine position vs lateral position. METHODS About 22 patients who underwent SEEG electrode implantation using Leksell frame fixation and Neuromate robot were included in this study and clustered according to the supine (n = 11) or lateral (n = 11) position. A total of 284 electrodes (Supine: n = 139; Lateral: n = 145) were analyzed. Postoperative Oarm images were co-registered with the preoperative plan on Voxim software. Cartesian coordinates of the entry point (EP) and target point (TP) were obtained from the planned trajectory and the implanted electrode. Three-dimensional error (Euclidian distance) and radial error for EP and TP were calculated. Wilcoxon rank sum test was used to compare lateral versus supine group. RESULTS Radial errors were similar between both groups. EP three-dimensional error was higher in the lateral position group (1.3 mm vs 1.7 mm, P = .004), whereas TP three-dimensional error was higher in the supine position group (2.9 mm vs 1.8 mm, P < .001). CONCLUSION SEEG electrode implantation using frame-based fixation and robot-assisted technique in the lateral position has similar accuracy compared to implantation in the supine position.

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Accuracy and Feasibility Analysis of SEEG Electrode Implantation using the VarioGuide Frameless Navigation System in Patients with Drug-Resistant Epilepsy

Journal of Neurological Surgery Part A Central European Neurosurgery ◽

10.1055/s-0040-1721002 ◽

2021 ◽

Author(s):

Shiwei Song ◽

Yihai Dai ◽

Zhen Chen ◽

Songsheng Shi

Keyword(s):

Navigation System ◽

Demographic Data ◽

Operating Time ◽

Small Region ◽

Target Point ◽

Localization Error ◽

Drug Resistant ◽

Electrode Implantation ◽

Computed Tomography Images ◽

Drug Resistant Epilepsy

Abstract Objective The objective of the study was to evaluate the feasibility and accuracy of frameless stereoelectroencephalography (SEEG) electrode implantation in patients with drug-resistant epilepsy using the VarioGuide system. Methods The VarioGuide frameless navigation system was used to implant SEEG electrodes in patients with medically drug-resistant epilepsy. Demographic data, surgery duration, number of electrodes, and complications were retrospectively analyzed. Accuracy was compared by measuring the distance between the planned and actual electrode positions as determined by postoperative computed tomography images. Results A total of 141 SEEG electrodes were implanted in 19 patients from May 2015 to December 2018 with an average of 7.42 (range: 4–10) leads per patient. The average entry point localization error (EPLE) was 1.96 ± 0.47 mm (range: 0.32–3.29) and average target point localization error (TPLE) was 2.47 ± 0.79 mm (range: 0.72–4.83). The average operating time per lead (OTPL) was 14.16 ± 2.68 minutes (range: 8.64–21.58). No complications occurred. Conclusion The VarioGuide frameless navigation system can be an effective method for SEEG electrode implantation in patients with drug-resistant epilepsy, particularly when the electrodes are concentrated in a relatively small region and the number of implanted electrodes is small.

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Placement of leads for stereotactic electroencephalography without the use of anchor bolts: technical note

Journal of Neurosurgery Pediatrics ◽

10.3171/2020.7.peds20403 ◽

2020 ◽

pp. 1-6

Author(s):

Torin Karsonovich ◽

Allyson Alexander ◽

Sarah Graber ◽

Brent R. O’Neill

Keyword(s):

Technical Note ◽

Entry Point ◽

Target Point ◽

Epileptogenic Zone ◽

Anchor Bolt ◽

Cranial Defect ◽

Common Technique ◽

Thin Bone ◽

The Mean ◽

Anchor Bolts

OBJECTIVEStereotactic electroencephalography (SEEG) is an increasingly common technique that neurosurgeons use to help identify the epileptogenic zone. The anchor bolt, which typically secures the electrode to the skull, can be problematic in very thin bone or in electrodes placed in the occiput.METHODSA technique is described to place electrodes without the use of an anchor bolt. Accuracy data for entry point, target point, and depth were collected and compared between electrodes placed with and those placed without an anchor bolt.RESULTSA total of 58 patients underwent placement of 793 electrodes, of which 25 were boltless. The mean entry and depth errors at target were equivalent, although there was a trend toward greater depth error with boltless electrodes (3.4 mm vs 2.01 mm and 2.59 mm in the bolted groups, respectively). The mean lateral target error was slightly but significantly smaller for boltless electrodes. The majority (60%) of boltless leads were placed into thin temporal squamous bone. The average skull thickness at the entry point for all boltless leads was 1.85 mm.CONCLUSIONSBoltless SEEG electrodes can be placed through thin bone, adjacent to a cranial defect, or in the occiput with equivalent accuracy to electrodes placed with anchor bolts.

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trans-Translation inhibitors bind to a novel site on the ribosome and clear Neisseria gonorrhoeae in vivo

Nature Communications ◽

10.1038/s41467-021-22012-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Zachary D. Aron ◽

Atousa Mehrani ◽

Eric D. Hoffer ◽

Kristie L. Connolly ◽

Pooja Srinivas ◽

...

Keyword(s):

Oral Dose ◽

Neisseria Gonorrhoeae ◽

Multiple Drug ◽

Specific Inhibition ◽

Drug Resistant ◽

Peptidyl Transfer ◽

Bacterial Ribosome ◽

Multiple Drug Resistant ◽

Unique Site

AbstractBacterial ribosome rescue pathways that remove ribosomes stalled on mRNAs during translation have been proposed as novel antibiotic targets because they are essential in bacteria and are not conserved in humans. We previously reported the discovery of a family of acylaminooxadiazoles that selectively inhibit trans-translation, the main ribosome rescue pathway in bacteria. Here, we report optimization of the pharmacokinetic and antibiotic properties of the acylaminooxadiazoles, producing MBX-4132, which clears multiple-drug resistant Neisseria gonorrhoeae infection in mice after a single oral dose. Single particle cryogenic-EM studies of non-stop ribosomes show that acylaminooxadiazoles bind to a unique site near the peptidyl-transfer center and significantly alter the conformation of ribosomal protein bL27, suggesting a novel mechanism for specific inhibition of trans-translation by these molecules. These results show that trans-translation is a viable therapeutic target and reveal a new conformation within the bacterial ribosome that may be critical for ribosome rescue pathways.

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Design, Fabrication, and Accuracy of a Novel Noncovering Lock-Mechanism Bilateral Patient-Specific Drill Guide Template for Nondeformed and Deformed Thoracic Spines

HSS Journal ® ◽

10.1177/1556331621996331 ◽

2021 ◽

pp. 155633162199633

Author(s):

Mehran Ashouri-Sanjani ◽

Shima Mohammadi-Moghadam ◽

Parisa Azimi ◽

Navid Arjmand

Keyword(s):

Thoracic Spine ◽

Sagittal Plane ◽

Ct Scanning ◽

Entry Point ◽

In Vivo Studies ◽

Patient Specific ◽

Plane Angle ◽

Severe Scoliosis ◽

3D Printed

Background: Pedicle screw (PS) placement has been widely used in fusion surgeries on the thoracic spine. Achieving cost-effective yet accurate placements through nonradiation techniques remains challenging. Questions/Purposes: Novel noncovering lock-mechanism bilateral vertebra-specific drill guides for PS placement were designed/fabricated, and their accuracy for both nondeformed and deformed thoracic spines was tested. Methods: One nondeformed and 1 severe scoliosis human thoracic spine underwent computed tomographic (CT) scanning, and 2 identical proportions of each were 3-dimensional (3D) printed. Pedicle-specific optimal (no perforation) drilling trajectories were determined on the CT images based on the entry point/orientation/diameter/length of each PS. Vertebra-specific templates were designed and 3D printed, assuring minimal yet firm contacts with the vertebrae through a noncovering lock mechanism. One model of each patient was drilled using the freehand and one using the template guides (96 pedicle drillings). Postoperative CT scans from the models with the inserted PSs were obtained and superimposed on the preoperative planned models to evaluate deviations of the PSs. Results: All templates fitted their corresponding vertebra during the simulated operations. As compared with the freehand approach, PS placement deviations from their preplanned positions were significantly reduced: for the nonscoliosis model, from 2.4 to 0.9 mm for the entry point, 5.0° to 3.3° for the transverse plane angle, 7.1° to 2.2° for the sagittal plane angle, and 8.5° to 4.1° for the 3D angle, improving the success rate from 71.7% to 93.5%. Conclusions: These guides are valuable, as the accurate PS trajectory could be customized preoperatively to match the patients’ unique anatomy. In vivo studies will be required to validate this approach.

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Exploring Galleria mellonella larval model to evaluate antibacterial efficacy of Cecropin A (1-7)- Melittin against multi-drug resistant enteroaggregative Escherichia coli

Pathogens and Disease ◽

10.1093/femspd/ftab010 ◽

2021 ◽

Author(s):

Jess Vergis ◽

S V S Malik ◽

Richa Pathak ◽

Manesh Kumar ◽

Nitin V Kurkure ◽

...

Keyword(s):

Escherichia Coli ◽

Galleria Mellonella ◽

In Vivo Model ◽

Drug Resistant ◽

Physiological Concentration ◽

Microbial Drug Resistance ◽

Cecropin A ◽

Screening And Identification

Abstract High throughput in vivo laboratory models is need for screening and identification of effective therapeutic agents to overcome microbial drug-resistance. This study was undertaken to evaluate in vivo antimicrobial efficacy of short-chain antimicrobial peptide- Cecropin A (1–7)-Melittin (CAMA) against three multi- drug resistant enteroaggregative Escherichia coli (MDR-EAEC) field isolates in a Galleria mellonella larval model. The minimum inhibitory concentration (MIC; 2.0 mg/L) and minimum bactericidal concentration (MBC; 4.0 mg/L) of CAMA were determined by microdilution assay. CAMA was found to be stable at high temperatures, physiological concentration of cationic salts and proteases; safe with sheep erythrocytes, secondary cell lines and commensal lactobacilli at lower MICs; and exhibited membrane permeabilisation. In vitro time-kill assay revealed concentration- and time-dependent clearance of MDR-EAEC in CAMA-treated groups at 30 min. CAMA- treated G. mellonella larvae exhibited an increased survival rate, reduced MDR-EAEC counts, immunomodulatory effect and proved non-toxic which concurred with histopathological findings. CAMA exhibited either an equal or better efficacy than the tested antibiotic control, meropenem. This study highlights the possibility of G. mellonella larvae as an excellent in vivo model for investigating the host-pathogen interaction, including the efficacy of antimicrobials against MDR-EAEC strains.

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