Name: stereo-electro-encephalo-graphy (seeg) with robotic assistance in the presurgical evaluation of medical refractory epilepsy: a technical note
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Description: Watch this Scientific Journal Video about Stereo-Electro-Encephalo-Graphy SEEG With Robotic Assistance in the Presurgical Evaluation of Medical Refractory Epilepsy: A Technical Note at JoVE.com

The authors have no acknowledgements.

Ethical statement: Our protocol follows the guidelines established by our institutional human research ethics committee.
1. Identification of Medically Refractory Epilepsy Patients
<ol>
	<li>Prior to invasive monitoring, evaluate allpatientswith noninvasive techniques, such as video-EEG monitoring, MRI, PET, ictalSPECT, and neuropsychological studies as described in 1 After discussion in multi-disciplinary meeting the decision whether or not to pursue invasive monitoring with SEEG...

<ol>
	<li>Serletis, D., Bulacio, J., Bingaman, W., Gonzalez-Martinez, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+stereotactic+approach+for+mapping+epileptic+networks:+a+prospective+study+of+200+patients.">The stereotactic approach for mapping epileptic networks: a prospective study of 200 patients.</a> J Neurosurg. 121, 1239-1246 (2014).</li><li>Bancaud, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epilepsy+after+60+years+of+age.+Experience+in+a+functional+neurosurgical+department.">Epilepsy after 60 years of age. Experience in a functional neurosurgical department.</a> Sem Hop. 46, 3138-3140 (1970).</li><li>Bancaud, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+stereotaxic+exploration+(SEEG)+of+epilepsy.">Functional stereotaxic exploration (SEEG) of epilepsy.</a> Electroencephalogr Clin Neurophysiol. 28, 85-86 (1970).</li><li>Talairach, J., Bancaud, J., Bonis, A., Szikla, G., Trottier, S., Vignal, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surgical+therapy+for+frontal+epilepsies.">Surgical therapy for frontal epilepsies.</a> Adv Neurol. 57, 707-732 (1992).</li><li>Vadera, S., Mullin, J., Bulacio, J., Najm, I., Bingaman, W., Gonzalez-Martinez, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stereo+electroencephalography+following+subdural+grid+placement+for+difficult+to+localize+epilepsy.">Stereo electroencephalography following subdural grid placement for difficult to localize epilepsy.</a> Neurosurgery. 72, 723-729 (2013).</li><li>Munari, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stereo-electroencephalography+methodology:+advantages+and+limits.">Stereo-electroencephalography methodology: advantages and limits.</a> Acta Neurol Scand Suppl. 152, 56-69 (1994).</li><li>Gonzalez-Martinez, J., Bulacio, J., Alexopoulos, A., Jehi, L., Bingaman, W., Najm, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stereoelectroencephalography+in+the+"difficult+to+localize"+refractory+focal+epilepsy+early+experience+from+a+North+American+epilepsy+center.">Stereoelectroencephalography in the "difficult to localize" refractory focal epilepsy early experience from a North American epilepsy center.</a> Epilepsia. 54, 323-330 (2013).</li><li>Gonzalez-Martinez, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stereotactic+placement+of+depth+electrodes+in+medically+intractable+epilepsy.+Technicalnote.">Stereotactic placement of depth electrodes in medically intractable epilepsy. Technicalnote.</a> J Neurosurg. 120, 639-664 (2014).</li><li>Nathoo, N., Lu, M. C., Vogelbaum, M., Barnett, G. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+Touch+with+Robotics:+Neurosurgery+for+the+Future.">In Touch with Robotics: Neurosurgery for the Future.</a> Neurosurgery. 56, 421-433 (2005).</li><li>De Almeida, A. N., Olivier, A., Quesney, F., Dubeau, F., Savard, G., Andermann, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficacy+of+and+morbidity+associated+with+stereoelectroencephalography+using+computerized+tomography-or+magnetic+resonance+imaging-guided+electrode+implantation.">Efficacy of and morbidity associated with stereoelectroencephalography using computerized tomography-or magnetic resonance imaging-guided electrode implantation.</a> J Neurosurg. 104, 483-487 (2006).</li><li>Cossu, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stereoelectroencephalography+in+the+presurgical+evaluation+of+focal+epilepsy+a+retrospective+analysis+of+215+procedures.">Stereoelectroencephalography in the presurgical evaluation of focal epilepsy a retrospective analysis of 215 procedures.</a> Neurosurgery. 57, 706-718 (2005).</li><li>Gonzalez-Martinez, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Robot-assisted+stereotactic+laser+ablation+in+medically+intractable+epilepsy:+operative+technique.">Robot-assisted stereotactic laser ablation in medically intractable epilepsy: operative technique.</a> Neurosurgery. 10, 167-172 (2014).</li><li>Guenot, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neurophysiological+monitoring+for+epilepsy+surgery:+the+Talairach+SEEG+method.+Indications,+results,+complications+and+therapeutic+applications+in+a+series+of+100+consecutive+cases.">Neurophysiological monitoring for epilepsy surgery: the Talairach SEEG method. Indications, results, complications and therapeutic applications in a series of 100 consecutive cases.</a> Stereotact Funct Neurosurg. 77, 29-32 (2001).</li><li>Kuzniecky, R. I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multimodality+MRI+in+mesial+temporal+sclerosis:+relative+sensitivity+and+specificity.">Multimodality MRI in mesial temporal sclerosis: relative sensitivity and specificity.</a> Neurology. 49 (3), 774-778 (1997).</li><li>Cardinale, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stereoelectroencephalography:+surgical+methodology,+safety,+and+stereotacticapplication+accuracy+in+500+procedures.">Stereoelectroencephalography: surgical methodology, safety, and stereotacticapplication accuracy in 500 procedures.</a> Neurosurgery. 72 (3), 353-366 (2013).</li></ol>

Here is presented the technique of SEEG insertion utilizing robotic stereotactic assistance. While SEEG was originally described using other methods of frame based stereotaxis, robot-assisted SEEG offers not only similar safety but superior accuracy and efficiency. The literature reports success at localizing the EZ in over 76% of cases, which is commiserate with other previous studies using alternative techniques.6,13,.
As with any invasive intracranial procedure, SEEG is not witho...

In medically refractory epilepsy there are many non-invasive pre-surgical tools (scalp EEG., magnetic resonance imaging (MRI), functional MRI, single photon emission computed tomography, positron emission topography, and magnetoencephalography). If these non-invasive evaluations fail to sufficiently localize or define the epileptic zone (EZ) then invasive recording may be indicated. Currently, subdural grids or Stereo-electro-encephalo-graphy (SEEG) are the two most prevalent methods of invasive monitoring. SEEG was originally developed in France in the 1950's by Jean Talairach and Jean Bancaud; recently it has mostly been used for invasive monitoring of refractory epilepsy patients in France.2-4 SEEG is the consists of stereotactically inserting intracerebral electrodes into the brain parenchyma to record brain electrical activity for an extended period of time. With the intracerebral electrical recordings many patients are able to have their EZ defined to allow for surgical resection. 
Despite this long history of success SEEG remains relatively rarely used for invasive recording in America. However, SEEG does offer several significant advantages; SEEG allows for 1) recording of deep structures, 2) bihemispheric recordings, 3) another recording option if subdural grids failed, and 4) mapping of epileptic networks in three dimensions, mainly in patients where non-lesional extra-temporal epilepsy is suspected.5-7 All of these benefits are achieved without requiring a large craniotomy. A recent technologic advance in SEEG surgery is the used of robotic guidance. This sophisticated development allows for improved operative times but safer and more accurate surgical implantation of electrodes.Recently published literature reviews the results of using two different techniques for SEEG insertion; a more traditional method utilizing stereotactic frames and a newer technique using robotic assistante for SEEG insertion.1, 8,15 the results were similarly successful with each method. 
With the advent of improved robotic assistance, the SEEG insertion technique has resulted in improved operative times. The robotic system is classified as a supervisory controlled system which means the surgeon plans the operation off line and implicitly specifies the motion the robot must follow to perform the operation.9 The robotic assist results in expedient transitions from one trajectory to the next for the placement of each intracranial electrode.

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			<td height="21" style="height:21px;width:216px;">ROSA</td>
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			<td style="width:167px;">robotic implantation system</td>
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			<td height="21" style="height:21px;width:216px;">electrodes</td>
			<td style="width:71px;">adtech</td>
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stereo-electro-encephalo-graphy (seeg) with robotic assistance in the presurgical evaluation of medical refractory epilepsy: a technical note

SEEG is a method and technique which is used for accurate, invasive recording of seizure activity via three dimensional recordings. In epilepsy patients who are deemed appropriate candidates for invasive recordings, the decision to monitor is made between the subdural grids versus SEEG. Invasive neuromonitoring for epilepsy is pursued in patients with complex, medically refractory epilepsy. The goal of invasive monitoring is to offer resective surgery with the hope of allowing seizure freedom. SEEG&#39;s advantages include access to deep cortical structures, an ability to localize the epileptogenic zone (EZ) when subdural grids have failed to do so, and in patients with non-lesional extra-temporal epilepsies. In this manuscript, we present a succinct historical overview of the SEEG and report on our experience with frameless stereotaxy under robotic. An imperative step of SEEG insertion is planning the electrode trajectories. In order to most effectively record ictal activity via SEEG trajectories should be planned based upon a hypothesis of where the seizure activity originates the presumed epileptogenic zone (EZ). The EZ hypothesis is based on a standardized preoperative workup including video-EEG monitoring, MRI (magnetic resonance imaging), PET (positron emission tomography), ictal SPECT (Single-photon emission computed tomography), and neuropsychological assessment. Using a suspected EZ, SEEG electrodes can be placed minimally invasively yet maintain accuracy and precision. Clinical results showed the ability to localize the EZ in 78% of difficult to localize epileptic patients.1

Recent results indicate that in one consecutive series of 78 patients who underwent SEEG insertion via robotic assistance had successful localization of the EZ in 76.2% of patients.1 That same study showed of the patients who went on to have surgical resection of EZ had grade 1 Engel seizure freedom in 67.8% of patients (Figure 4). Morbidity rate is 2.5%. Permanent morbidity was noticed is 1 patient (1.2%). Per electrode, it was shown to have a wound infection ...

Watch this Scientific Journal Video about Stereo-Electro-Encephalo-Graphy SEEG With Robotic Assistance in the Presurgical Evaluation of Medical Refractory Epilepsy: A Technical Note at JoVE.com

Stereo-Electro-Encephalo-Graphy SEEG With Robotic Assistance in the Presurgical Evaluation of Medical Refractory Epilepsy: A Technical Note

Stereo-electroencephalography (SEEG) aids in localization of epileptogenic zones, however, remains relatively underutilized in the United States. The goal of this abstract is to provide a brief introduction to the technique of SEEG and further a detailed technique of using robotic assistance in the placement of SEEG electrodes.

Stereo-Electro-Encephalo-Graphy (SEEG) With Robotic Assistance in the Presurgical Evaluation of Medical Refractory Epilepsy: A Technical Note

SEEG is a method and technique which is used for accurate, invasive recording of seizure activity via three dimensional recordings. In epilepsy patients ...

The overall goal of this surgical intervention is to localize the patient's epileptogenic focus, potentially allowing further intervention for the ultimate goal of seizure freedom. Stereo-electro-encephalo-graphy, also known as SEEG, it's a method and technique designed to better localize the epileptogenic zone, which is the minimal area in the brain that is responsible for the generation of seizures. The main advantages of SEEG, compared to subdurals, is that SEEG, it's a minimally invasive method that does not require craniotomy.It carries minimal complication rate, and allows the three-dimensional mapping of the epileptogenic brain. After developing an implantation strategy based upon the hypothesized epileptogenic zone, select new patient on the robotic assistance device to create a new encounter. Then, click on create trajectory, and select the appropriate entry and end-points that correspond with the desired trajectory.When the device is ready, arrange the patient on the surgical table in the supine position. After prepping the patient, select register on the robotic assistance device, and follow the prompts to complete the registration process using the surface landmark registration based on the facial features. When the registration is complete, use guidance assistance from the robotic stereotactic system to bore the first bolt-hole in the skull with a 2.5 millimeter drill bit.Then, insert the monopolar coagulator probe to open the dura mater, and use the robotic stereotactic system to screw the first implantation bolt into the skull. Use the implanted bolt to guide the insertion of the stylet probe to create the initial trajectory, and insert the first electrode. Then, secure the electrode to the bolt to prevent further displacement and cerebrospinal fluid leakage.After inserting and connecting the rest of the electrodes in the same manner, place the iodine solution soaked gauze around each of the bolt caps. Then connect the electrodes to the EEG recording machine to confirm their proper function and obtain intraoperative x-rays in the lateral and anterior/posterior skull to confirm that the electrodes have been placed with the correct trajectories. Now, transfer the patient to the epilepsy monitoring unit, and monitor the patient for seizure activity both clinically and electrographically via the stereo-electro-encephalo-graphy electrode recording, administering analgesia as appropriate.Wrap the head. When sufficient ictal data has been recorded, return the patient to the operating room for removal of the stereo-electro-encephalo-graphy electrodes under conscious sedation. Then, after removing the head wrap, and cutting the electrode wires, prep the remaining bolts and tails of the electrodes with iodinated gel, and remove the first bolt cap with twisting.Next, gently pull the corresponding electrode out along the axis of its insertion, and twist out the bolt. Before moving on to the next electrode, close the defect left by the bolt with one stitch of nylon suture. Then, repeat the removal procedure for each of the other electrodes.After all of the electrodes have been removed, cover the stitch areas with antibiotic ointment and a loose head wrap. Finally, image the patient to confirm the absence of any residual hardware. Here, temporal, temporal-occipital, temporo-parietal-occipital, fronto-temporal, fronto-parietal-insular, perisylvian, and bi-temporal and right frontal insertion plans are shown.The black dots represent the entry points of the electrodes implanted in an orthogonal fashion, and the black lines represent the electrodes in oblique trajectories. Recent results indicate that in one consecutive series of 78 patients who underwent stereo-electro-encephalo-graphy insertion via robotic assistance, successful localization of the epileptogenic zone was achieved in 76.2%of patients. In the same study, surgical resection of the epilepogenic zone was demonstrated to impart Grade 1 Engel seizure freedom in 67.8%of patients.Note that the observed morbidity rate of the procedure is 2.5%with a permanent morbidity notice of one patient, or 1.2%Per electrode, wound infection and intracranial hematoma rates of 0.08%were also observed. The SEEG procedure, it should take approximately two to three hours. Although it's considered to be a minimally invasive procedure, it does carry some risks, which are approximately 1%The main risks are intracranial bleedings.While you are watching this movie, you will be able to understand how to perform a robotic SEEG implantation.

stereo-electro-encephalo-graphy-seeg-with-robotic-assistance

Research

JoVE Journal

Medicine

Technical Aspects of the Mouse Aortocaval Fistula

Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta and inferior vena cava (IVC) are exposed. The proximal infrarenal aorta and the distal aorta are dissected for clamp placement and needle puncture, respectively. Special attention is paid to avoid dissection between the aorta and the IVC. After clamping the aorta, a 25 G needle is used to puncture both walls of the aorta into the IVC. The surrounding connective tissue is used for hemostatic compression. Successful creation of the AVF will show pulsatile arterial blood flow in the IVC. Further confirmation of successful AVF can be achieved by post-operative Doppler ultrasound.

The goal is to produce an arteriovenous fistula that is simple and reproducible. This method does not use sutures or glue adhesive. Therefore the samples can be used with the least amount of foreign materials for analysis.

Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta ...

Network Analysis of the Default Mode Network Using Functional Connectivity MRI in Temporal Lobe Epilepsy

Functional connectivity MRI (fcMRI) is an fMRI method that examines the connectivity of different brain areas based on the correlation of BOLD signal fluctuations over time. Temporal Lobe Epilepsy (TLE) is the most common type of adult epilepsy and involves multiple brain networks. The default mode network (DMN) is involved in conscious, resting state cognition and is thought to be affected in TLE where seizures cause impairment of consciousness. The DMN in epilepsy was examined using seed based fcMRI. The anterior and posterior hubs of the DMN were used as seeds in this analysis. The results show a disconnection between the anterior and posterior hubs of the DMN in TLE during the basal state. In addition, increased DMN connectivity to other brain regions in left TLE along with decreased connectivity in right TLE is revealed. The analysis demonstrates how seed-based fcMRI can be used to probe cerebral networks in brain disorders such as TLE.

The Default Mode Network (DMN) in Temporal Lobe Epilepsy (TLE) is analyzed in the resting state of the brain using seed-based functional connectivity MRI (fcMRI).

Functional connectivity MRI (fcMRI) is an fMRI method that examines the connectivity of different brain areas based on the correlation of BOLD signal ...

A Multimodal Imaging- and Stimulation-based Method of Evaluating Connectivity-related Brain Excitability in Patients with Epilepsy

Resting-state functional connectivity MRI (rs-fcMRI) is a technique that identifies connectivity between different brain regions based on correlations over time in the blood-oxygenation level dependent signal. rs-fcMRI has been applied extensively to identify abnormalities in brain connectivity in different neurologic and psychiatric diseases. However, the relationship among rs-fcMRI connectivity abnormalities, brain electrophysiology and disease state is unknown, in part because the causal significance of alterations in functional connectivity in disease pathophysiology has not been established. Transcranial Magnetic Stimulation (TMS) is a technique that uses electromagnetic induction to noninvasively produce focal changes in cortical activity. When combined with electroencephalography (EEG), TMS can be used to assess the brain's response to external perturbations. Here we provide a protocol for combining rs-fcMRI, TMS and EEG to assess the physiologic significance of alterations in functional connectivity in patients with neuropsychiatric disease. We provide representative results from a previously published study in which rs-fcMRI was used to identify regions with abnormal connectivity in patients with epilepsy due to a malformation of cortical development, periventricular nodular heterotopia (PNH). Stimulation in patients with epilepsy resulted in abnormal TMS-evoked EEG activity relative to stimulation of the same sites in matched healthy control patients, with an abnormal increase in the late component of the TMS-evoked potential, consistent with cortical hyperexcitability. This abnormality was specific to regions with abnormal resting-state functional connectivity. Electrical source analysis in a subject with previously recorded seizures demonstrated that the origin of the abnormal TMS-evoked activity co-localized with the seizure-onset zone, suggesting the presence of an epileptogenic circuit. These results demonstrate how rs-fcMRI, TMS and EEG can be utilized together to identify and understand the physiological significance of abnormal brain connectivity in human diseases.

Resting-state functional-connectivity MRI has identified abnormalities in patients with a wide range of neuropsychiatric disorders, including epilepsy due to malformations of cortical development. Transcranial Magnetic Stimulation in combination with EEG can demonstrate that patients with epilepsy have cortical hyperexcitability in regions with abnormal connectivity.

Resting-state functional connectivity MRI (rs-fcMRI) is a technique that identifies connectivity between different brain regions based on correlations ...

Network Analysis of Foramen Ovale Electrode Recordings in Drug-resistant Temporal Lobe Epilepsy Patients

Approximately 30% of epilepsy patients are refractory to antiepileptic drugs. In these cases, surgery is the only alternative to eliminate/control seizures. However, a significant minority of patients continues to exhibit post-operative seizures, even in those cases in which the suspected source of seizures has been correctly localized and resected. The protocol presented here combines a clinical procedure routinely employed during the pre-operative evaluation of temporal lobe epilepsy (TLE) patients with a novel technique for network analysis. The method allows for the evaluation of the temporal evolution of mesial network parameters. The bilateral insertion of foramen ovale electrodes (FOE) into the ambient cistern simultaneously records electrocortical activity at several mesial areas in the temporal lobe. Furthermore, network methodology applied to the recorded time series tracks the temporal evolution of the mesial networks both interictally and during the seizures. In this way, the presented protocol offers a unique way to visualize and quantify measures that considers the relationships between several mesial areas instead of a single area.

This protocol describes a procedure to track the evolution of mesial network measures in temporal lobe epilepsy (TLE) patients. It is based on the combination of intracranial recordings with a novel numerical technique for data analysis. Specifically, we present a protocol for network analyses of foramen ovale recordings.

Approximately 30% of epilepsy patients are refractory to antiepileptic drugs. In these cases, surgery is the only alternative to eliminate/control ...

Interictal High Frequency Oscillations Detected with Simultaneous Magnetoencephalography and Electroencephalography as Biomarker of Pediatric Epilepsy

Crucial to the success of epilepsy surgery is the availability of a robust biomarker that identifies the Epileptogenic Zone (EZ). High Frequency Oscillations (HFOs) have emerged as potential presurgical biomarkers for the identification of the EZ in addition to Interictal Epileptiform Discharges (IEDs) and ictal activity. Although they are promising to localize the EZ, they are not yet suited for the diagnosis or monitoring of epilepsy in clinical practice. Primary barriers remain: the lack of a formal and global definition for HFOs; the consequent heterogeneity of methodological approaches used for their study; and the practical difficulties to detect and localize them noninvasively from scalp recordings. Here, we present a methodology for the recording, detection, and localization of interictal HFOs from pediatric patients with refractory epilepsy. We report representative data of HFOs detected noninvasively from interictal scalp EEG and MEG from two children undergoing surgery.
The underlying generators of HFOs were localized by solving the inverse problem and their localization was compared to the Seizure Onset Zone (SOZ) as this was defined by the epileptologists. For both patients, Interictal Epileptogenic Discharges (IEDs) and HFOs were localized with source imaging at concordant locations. For one patient, intracranial EEG (iEEG) data were also available. For this patient, we found that the HFOs localization was concordant between noninvasive and invasive methods. The comparison of iEEG with the results from scalp recordings served to validate these findings. To our best knowledge, this is the first study that presents the source localization of scalp HFOs from simultaneous EEG and MEG recordings comparing the results with invasive recordings. These findings suggest that HFOs can be reliably detected and localized noninvasively with scalp EEG and MEG. We conclude that the noninvasive localization of interictal HFOs could significantly improve the presurgical evaluation for pediatric patients with epilepsy.

High Frequency Oscillations (HFOs) have emerged as presurgical biomarkers for the identification of the epileptogenic zone in pediatric patients with medically refractory epilepsy. A methodology for the noninvasive recording, detection, and localization of HFOs with simultaneous scalp electroencephalography (EEG) and magnetoencephalography (MEG) is presented.

Crucial to the success of epilepsy surgery is the availability of a robust biomarker that identifies the Epileptogenic Zone (EZ). High Frequency ...

Emergency Undocking in Robotic Surgery: A Simulation Curriculum

The following is a training platform to allow robotic surgeons to develop the skills necessary to lead an interprofessional team in emergency undocking of a robotic system. In traditional robotic training for surgeons, a brief web based overview of performing an emergency undocking is provided during initial introductory training to the robotics system. During such a process, there is no training in delineation of interdisciplinary roles for operating room (OR) personnel. The training presented here uses formative simulation and debriefing followed by a lecture. For the simulation, a modified gynecologic simulator is draped in a steep trendelenburg position consistent with most gynecologic laparoscopic surgery. The training torso is modified using tubing hooked to pressure bags of red food colored IV fluid used to simulate a catastrophic vessel injury on demand. Positioned throughout the operating room setting is an interprofessional team consisting of embedded standardized persons (ESPs) to fulfill the roles of a circulating nurse, scrub nurse, anesthesiologist, and bedside assist surgeon. Robotic surgeons are presented a case scenario necessitating emergency undocking, and given control of the robotic instruments. The scenario is terminated following either successful completion of an emergency undock, or at five minutes due to the emergent nature of the case. A debriefing session with hands on training of the steps to emergency undocking, necessary equipment, troubleshooting techniques, and operating room personnel roles follows the simulation. The learners are presented with a short lecture reemphasizing the material presented in the debriefing for their own self-study. This training results in improved time accessing the patient, improved knowledge, confidence, and completion of critical actions, and can be replicated in most institutions. All robotic surgeons should be able to demonstrate competence in this crucial intervention. A limitation of the curriculum is ability to access the in-situ environment for training purposes.

This training platform is designed to allow robotic surgeons to develop the skills necessary to lead an interprofessional team in emergency undocking of the robotic system. Training includes the utilization of the technology and equipment to perform an emergency undocking, as well as delineation of roles for such a scenario.

The following is a training platform to allow robotic surgeons to develop the skills necessary to lead an interprofessional team in emergency undocking of ...

Technical Detail for Robot Assisted Pancreaticoduodenectomy

Since its first report in 2003, robotic pancreaticoduodenectomy (RPD) has gained popularity among pancreatic surgeons. Inherent advantages of the robotic platform, including three-dimensional vision, wristed instruments, and improved ergonomics, allow the surgeon to recapitulate the principles of open pancreatoduodenectomy allowing safe oncologic dissection, hemostasis, and meticulous reconstruction. Over the course of the past decade, significant strides have been achieved in outlining the safety, feasibility, and learning curve of the robotic Whipple. When performed by high volume pancreatic surgeons experienced in RPD, recent comparative effectiveness studies show potential advantages compared to the open technique, including reductions in hospital stay and morbidity. National data also show reductions in conversion rates compared to its laparoscopic counterpart. Although long-term oncologic data are still needed, short-term oncologic surrogates of margin resection and lymph node harvest suggest no compromise in oncologic outcomes. As pancreatic surgeons increasingly integrate robotics into their practice, proficiency-based training and credentialing will be necessary for the safe application and dissemination of RPD. Here, we provide the detailed steps of a robotic pancreaticoduodenectomy performed at the University of Pittsburgh Medical Center.&#160;

The following manuscript details a stepwise approach to the robot-assisted pancreaticoduodenectomy performed at the University of Pittsburgh Medical Center.

Since its first report in 2003, robotic pancreaticoduodenectomy (RPD) has gained popularity among pancreatic surgeons. Inherent advantages of the robotic ...

Assessment of Static Graviceptive Perception in the Roll-Plane using the Subjective Visual Vertical Paradigm

Vestibular disorders are among the most common syndromes in medicine. In recent years, new vestibular diagnostic systems have been introduced that allow the examination of all semicircular canals in the clinical setting. Assessment methods of the otolithic system, which is responsible for the perception of linear acceleration and perception of gravity, are far less in clinical use. There are several experimental approaches for measuring the perception of gravity. The most frequently used method is the determination of the subjective visual vertical. This is usually measured with the head in an upright position. We present here an assessment method for testing otolith function in the roll plane. The subjective visual vertical is measured in the head upright position as well as with head inclination of &#177; 15&#176; and &#177; 30&#176; in the roll plane. This extended functional paradigm is an easy-to-perform clinical test of otolith function and ensures increased information content for the detection of impaired graviceptive perception.

The perception of gravity is commonly determined by the subjective visual vertical in the head upright position. The additional assessment at head tilts of &#177; 15&#176; and &#177; 30&#176; in the roll plane ensures increased information content for the detection of impaired graviceptive perception.

Vestibular disorders are among the most common syndromes in medicine. In recent years, new vestibular diagnostic systems have been introduced that allow ...

Evaluation of Cerebral Blood Flow Autoregulation in the Rat Using Laser Doppler Flowmetry

When investigating the body&#39;s mechanisms for regulating cerebral blood flow, a relative measurement of microcirculatory blood flow can be obtained using laser Doppler flowmetry (LDF). This paper demonstrates a closed skull preparation that allows cerebral blood flow to be assessed without penetrating the skull or installing a chamber or cerebral window. To evaluate autoregulatory mechanisms, a model of controlled blood pressure reduction via graded hemorrhage can be utilized while simultaneously employing LDF. This enables the real time tracking of the relative changes in the blood flow in response to reductions in arterial blood pressure produced by the withdrawal of circulating blood volume. This paradigm is a valuable approach to study cerebral blood flow autoregulation during reductions in arterial blood pressure and, with minor modifications in the protocol, is also valuable as an experimental model of hemorrhagic shock. In addition to evaluating autoregulatory responses, LDF can be used to monitor the cortical blood flow when investigating metabolic, myogenic, endothelial, humoral, or neural mechanisms that regulate cerebral blood flow and the impact of various experimental interventions and pathological conditions on cerebral blood flow.

This article demonstrates the use of laser Doppler flowmetry to evaluate the ability of the cerebral circulation to autoregulate its blood flow during reductions in arterial blood pressure.

When investigating the body&#39;s mechanisms for regulating cerebral blood flow, a relative measurement of microcirculatory blood flow can be obtained ...

Development and Evaluation of 3D-Printed Cardiovascular Phantoms for Interventional Planning and Training

Catheter-based interventions are standard treatment options for cardiovascular pathologies. Therefore, patient-specific models could help training physicians&#39; wire-skills as well as improving planning of interventional procedures. The aim of this study was to develop a manufacturing process of patient-specific 3D-printed models for cardiovascular interventions.
To create a 3D-printed elastic phantom, different 3D-printing materials were compared to porcine biological tissues (i.e., aortic tissue) in terms of mechanical characteristics. A fitting material was selected based on comparative tensile tests and specific material thicknesses were defined. Anonymized contrast-enhanced CT-datasets were collected retrospectively. Patient-specific volumetric models were extracted from these datasets and subsequently 3D-printed. A pulsatile flow loop was constructed to simulate the intraluminal blood flow during interventions. Models&#39; suitability for clinical imaging was assessed by x-ray imaging, CT, 4D-MRI and (Doppler) ultrasonography. Contrast medium was used to enhance visibility in x-ray-based imaging. Different catheterization techniques were applied to evaluate the 3D-printed phantoms in physicians&#39; training as well as for pre-interventional therapy planning.
Printed models showed a high printing resolution (~30 &#181;m) and mechanical properties of the chosen material were comparable to physiological biomechanics. Physical and digital models showed high anatomical accuracy when compared to the underlying radiological dataset. Printed models were suitable for ultrasonic imaging as well as standard x-rays. Doppler ultrasonography and 4D-MRI displayed flow patterns and landmark characteristics (i.e., turbulence, wall shear stress) matching native data. In a catheter-based laboratory setting, patient-specific phantoms were easy to catheterize. Therapy planning and training of interventional procedures on challenging anatomies (e.g., congenital heart disease (CHD)) was possible.
Flexible patient-specific cardiovascular phantoms were 3D-printed, and the application of common clinical imaging techniques was possible. This new process is ideal as a training tool for catheter-based (electrophysiological) interventions and can be used in patient-specific therapy planning.

Here we present development of a mock circulation setup for multimodal therapy evaluation, pre-interventional planning, and physician-training on cardiovascular anatomies. With the application of patient-specific tomographic scans, this setup is ideal for therapeutic approaches, training, and education in individualized medicine.