Stereo-Encephalography Versus Subdural Electrodes for Seizure Localization

Podkorytova, Irina; Hoes, Kathryn; Lega, Bradley

doi:10.1016/j.nec.2015.08.008

Cited by 39 publications

(38 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…5,11,12 Although MRgLITT is a promising approach to the treatment of MTLE, it is still a relatively new procedure. [19][20][21][22] The likelihood of achieving seizure freedom with SLAH in this challenging patient population remains largely unknown. Oneyear seizure freedom rates have been reported in fewer than 50 patients, [2][3][4][5][6]13 and it will be several years before the results of the Stereotactic Laser Ablation for Temporal Lobe Epilepsy (SLATE) trial-an ongoing, large prospective cohort study-are available.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Laser ablation is effective for temporal lobe epilepsy with and without mesial temporal sclerosis if hippocampal seizure onsets are localized by stereoelectroencephalography

Youngerman

Anbarasan

et al. 2018

Epilepsia

View full text Add to dashboard Cite

We report similar rates of seizure freedom following SLAH in patients with MTS and SEEG-confirmed, non-MTS MTLE. Consistent with early literature, these rates are slightly lower than typically observed with surgical resection (60%-80%). However, SLAH is less invasive than open surgery, with shorter hospital stays and recovery, and severe procedural complications are rare. SLAH may be a reasonable first-line surgical option for patients with both MTS and SEEG confirmed, non-MTS MTLE.

show abstract

Section: Introductionmentioning

confidence: 99%

“…However, with invasive monitoring and the growth of robot-assisted stereoelectroencephalography (SEEG), the seizure-onset zone can often be localized to the mesial temporal lobe structures. [19][20][21][22] The likelihood of achieving seizure freedom with SLAH in this challenging patient population remains largely unknown.…”

Section: Introductionmentioning

confidence: 99%

Laser ablation is effective for temporal lobe epilepsy with and without mesial temporal sclerosis if hippocampal seizure onsets are localized by stereoelectroencephalography

Youngerman

Anbarasan

et al. 2018

Epilepsia

View full text Add to dashboard Cite

show abstract

“…However, in many cases, such as non-lesional or extratemporal lobe epilepsy, scalp EEG recording is not adequate for localising epileptogenic foci and additional invasive telemetry methods are necessary ( Duncan, 2011 ). This may be accomplished with implantation of subdural electrode mats on the exposed surface of the brain (electrocorticography (ECoG)) or insertion of depth electrodes into a lesion or the brain parenchyma (stereoencephalography) ( Podkorytova et al, 2016 ). Distinctive ictal and/or interictal discharges, such as spikes, sharp waves and spike-and-wave discharges (SWDs), may be evident in these recordings ( Nair, 2016 ).…”

Section: Introductionmentioning

confidence: 99%

Imaging fast electrical activity in the brain during ictal epileptiform discharges with electrical impedance tomography

Hannan

Faulkner

Aristovich

et al. 2018

NeuroImage: Clinical

View full text Add to dashboard Cite

Electrical Impedance Tomography (EIT) is an emerging medical imaging technique which can produce tomographic images of internal impedance changes within an object using non-penetrating surface electrodes. It has previously been used to image impedance changes due to neuronal depolarisation during evoked potentials in the rat somatosensory cortex with a resolution of 2 ms and <200 μm, using an epicortical electrode array. The purpose of this work was to use this technique to elucidate the intracortical spatiotemporal trajectory of ictal spike-and-wave discharges (SWDs), induced by electrical stimulation in an acute rat model of epilepsy, throughout the cerebral cortex. Seizures lasting 16.5 ± 5.3 s with repetitive 2–5 Hz SWDs were induced in five rats anaesthetised with fentanyl-isoflurane. Transfer impedance measurements were obtained during each seizure with a 57-electrode epicortical array by applying 50 μA current at 1.7 kHz to two electrodes and recording voltages from all remaining electrodes. Images were reconstructed from averaged SWD-related impedance traces obtained from EIT measurements in successive seizures. We report the occurrence of reproducible impedance changes during the initial spike phase, which had an early onset in the whisker barrel cortex and spread posteriorly, laterally and ventrally over 20 ms (p < 0.03125, N = 5). These findings, which confirm and extend knowledge of SWD initiation and expression, suggest that EIT is a valuable neuroimaging tool for improving understanding of neural circuits implicated in epileptic phenomena.

show abstract

“…These arrays record primarily from the cortical surface, poorly resolving deeper brain structures that can generate seizures, such as the cingulate gyrus and insula. Stereotaxic electroencephalography (SEEG) utilizes arrays of stereotaxically placed, penetrating depth electrodes to map seizures throughout the cortex, offering a less invasive alternative to ECoG that can record from deeper structures (Lang et al 2016;Podkorytova et al 2016). Although the resolution of SEEG electrodes is higher than for ECoG, with typical interelectrode spacing of 3.5 mm (Narizzano et al 2017), both recording methods can miss important epileptic activity occurring in the cortex on a submillimeter scale (Schevon et al 2010;Stead et al 2010;Viventi et al 2011).…”

Section: Introductionmentioning

confidence: 99%

Spatiotemporal evolution of focal epileptiform activity from surface and laminar field recordings in cat neocortex

Bink

Sedigh-Sarvestani

Fernández-Lamo

et al. 2018

Journal of Neurophysiology

View full text Add to dashboard Cite

New devices that use targeted electrical stimulation to treat refractory localization-related epilepsy have shown great promise, although it is not well known which targets most effectively prevent the initiation and spread of seizures. To better understand how the brain transitions from healthy to seizing on a local scale, we induced focal epileptiform activity in the visual cortex of five anesthetized cats with local application of the GABA blocker picrotoxin while simultaneously recording local field potentials on a high-resolution electrocorticography array and laminar depth probes. Epileptiform activity appeared in the form of isolated events, revealing a consistent temporal pattern of ictogenesis across animals with interictal events consistently preceding the appearance of seizures. Based on the number of spikes per event, there was a natural separation between seizures and shorter interictal events. Two distinct spatial regions were seen: an epileptic focus that grew in size as activity progressed, and an inhibitory surround that exhibited a distinct relationship with the focus both on the surface and in the depth of the cortex. Epileptiform activity in the cortical laminae was seen concomitant with activity on the surface. Focus spikes appeared earlier on electrodes deeper in the cortex, suggesting that deep cortical layers may be integral to recruiting healthy tissue into the epileptic network and could be a promising target for interventional devices. Our study may inform more effective therapies to prevent seizure generation and spread in localization-related epilepsies. NEW & NOTEWORTHY We induced local epileptiform activity and recorded continuous, high-resolution local field potentials from the surface and depth of the visual cortex in anesthetized cats. Our results reveal a consistent pattern of ictogenesis, characterize the spatial spread of the epileptic focus and its relationship with the inhibitory surround, and show that focus activity within events appears earliest in deeper cortical layers. These findings have potential implications for the monitoring and treatment of refractory epilepsy.

show abstract

Stereo-Encephalography Versus Subdural Electrodes for Seizure Localization

Cited by 39 publications

References 19 publications

Laser ablation is effective for temporal lobe epilepsy with and without mesial temporal sclerosis if hippocampal seizure onsets are localized by stereoelectroencephalography

Laser ablation is effective for temporal lobe epilepsy with and without mesial temporal sclerosis if hippocampal seizure onsets are localized by stereoelectroencephalography

Imaging fast electrical activity in the brain during ictal epileptiform discharges with electrical impedance tomography

Spatiotemporal evolution of focal epileptiform activity from surface and laminar field recordings in cat neocortex

Contact Info

Product

Resources

About