Does Tc-99m ECD ictal brain SPECT have incremental value in localization of epileptogenic zone and predicting postoperative seizure freedom in cases with discordant video electroencephalogram and MRI findings?

Object During the presurgical evaluation of patients with medically intractable focal epilepsy, a variety of noninvasive studies are performed to localize the hypothetical epileptogenic zone and guide the resection. Magnetoencephalography (MEG) is becoming increasingly used in the clinical realm for this purpose. No investigators have previously reported on coregisteration of MEG clusters with postoperative resection cavities to evaluate whether complete “clusterectomy” (resection of the area associated with MEG clusters) was performed or to compare these findings with postoperative seizure-free outcomes. Methods The authors retrospectively reviewed the charts and imaging studies of 65 patients undergoing MEG followed by resective epilepsy surgery from 2009 until 2012 at the Cleveland Clinic. Preoperative MEG studies were fused with postoperative MRI studies to evaluate whether clusters were within the resected area. These data were then correlated with postoperative seizure freedom. Results Sixty-five patients were included in this study. The average duration of follow-up was 13.9 months, the mean age at surgery was 23.1 years, and the mean duration of epilepsy was 13.7 years. In 30 patients, the main cluster was located completely within the resection cavity, in 28 it was completely outside the resection cavity, and in 7 it was partially within the resection cavity. Seventy-four percent of patients were seizure free at 12 months after surgery, and this rate decreased to 60% at 24 months. Improved likelihood of seizure freedom was seen with complete clusterectomy in patients with localization outside the temporal lobe (extra–temporal lobe epilepsy) (p = 0.04). Conclusions In patients with preoperative MEG studies that show clusters in surgically accessible areas outside the temporal lobe, we suggest aggressive resection to improve the chances for seizure freedom. When the cluster is found within the temporal lobe, further diagnostic testing may be required to better localize the epileptogenic zone.

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Epilepsy Surgery in Children and Adolescents

Neurology International Open ◽

10.1055/s-0043-102834 ◽

2017 ◽

Vol 1 (02) ◽

pp. E86-E97

Author(s):

Georgia Ramantani ◽

Josef Zentner

Keyword(s):

Children And Adolescents ◽

Epilepsy Surgery ◽

Focal Cortical Dysplasia ◽

Neurological Deficits ◽

Epilepsy Syndrome ◽

Seizure Freedom ◽

Epileptogenic Zone ◽

Presurgical Evaluation ◽

Effective Treatment Option ◽

Postoperative Seizure

AbstractEpilepsy surgery has been established in recent years as an effective treatment option for children and adolescents with pharmacoresistant structural epilepsies. Thanks to advances in neurosurgery, anesthesia and intensive care, epilepsy surgery is also possible in infants with excellent results. Epilepsy surgery should be considered in children with structural epilepsies and presurgical evaluation should be initiated at the latest when the criteria for pharmacoresistance are met. Focal cortical dysplasia and glioneuronal tumors are the most common etiologies in pediatric cohorts. Postoperative seizure-freedom depends on completeness of resection. In childhood, multilobular and hemispheric interventions predominate, whereas adults commonly undergo temporal resections. The extent of resections decreases with age. Younger children often require larger resections, but have higher capacities to compensate for neurological deficits, due to functional plasticity. Postoperative seizure freedom depends on the epilepsy syndrome, underlying etiology and accurate demarcation of the epileptogenic zone. Postoperatively, two-thirds of the children remain seizure-free in the long-term. Significant improvements in cognitive development are observed with seizure control. In addition to the development of non-invasive methods for presurgical evaluation, it is crucial to reduce the latency between the establishment of pharmacoresistance, presurgical evaluation and surgical treatment in suitable candidates. Multicentric studies with longer observation intervals are urgently needed in order to identify predictors of seizure freedom and favorable developmental trajectories, to facilitate the selection of optimal candidates and to improve counseling of patients and their families.

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Seizure outcome in temporal glioblastoma surgery: lobectomy as a supratotal resection regime outclasses conventional gross-total resection

Journal of Neuro-Oncology ◽

10.1007/s11060-021-03705-x ◽

2021 ◽

Author(s):

Valeri Borger ◽

Motaz Hamed ◽

Inja Ilic ◽

Anna-Laura Potthoff ◽

Attila Racz ◽

...

Keyword(s):

Tumor Resection ◽

Temporal Lobectomy ◽

Secondary Outcome ◽

Seizure Outcome ◽

Seizure Freedom ◽

Secondary Outcome Measure ◽

Total Resection ◽

Class 1 ◽

Postoperative Seizure ◽

The Impact

Abstract Introduction The postoperative seizure freedom represents an important secondary outcome measure in glioblastoma surgery. Recently, supra-total glioblastoma resection in terms of anterior temporal lobectomy (ATL) has gained growing attention with regard to superior long-term disease control for temporal-located glioblastoma compared to conventional gross-total resections (GTR). However, the impact of ATL on seizure outcome in these patients is unknown. We therefore analyzed ATL and GTR as differing extents of resection in regard of postoperative seizure control in patients with temporal glioblastoma and preoperative symptomatic seizures. Methods Between 2012 and 2018, 33 patients with preoperative seizures underwent GTR or ATL for temporal glioblastoma at the authors’ institution. Seizure outcome was assessed postoperatively and 6 months after tumor resection according to the International League Against Epilepsy (ILAE) classification and stratified into favorable (ILAE class 1) versus unfavorable (ILAE class 2–6). Results Overall, 23 out of 33 patients (70%) with preoperative seizures achieved favorable seizure outcome following resection of temporal located glioblastoma. For the ATL group, postoperative seizure freedom was present in 13 out of 13 patients (100%). In comparison, respective rates for the GTR group were 10 out of 20 patients (50%) (p = 0.002; OR 27; 95% CI 1.4–515.9). Conclusions ATL in terms of a supra-total resection strategy was associated with superior favorable seizure outcome following temporal glioblastoma resection compared to GTR. Regarding above mentioned survival benefit following ATL compared to GTR, ATL as an aggressive supra-total resection regime might constitute the surgical modality of choice for temporal-located glioblastoma.

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Association Between Anatomical Location of Surgically Induced Lesions and Postoperative Seizure Outcome in Temporal Lobe Epilepsy

Neurology ◽

10.1212/wnl.0000000000013033 ◽

2021 ◽

pp. 10.1212/WNL.0000000000013033

Author(s):

Ezequiel Gleichgerrcht ◽

Daniel L. Drane ◽

Simon Sean Keller ◽

Kathryn A. Davis ◽

Robert Gross ◽

...

Keyword(s):

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Anterior Commissure ◽

Piriform Cortex ◽

Seizure Outcome ◽

Seizure Freedom ◽

Anatomical Location ◽

Surgical Interventions ◽

Postoperative Seizure ◽

Promising Source

Objective:To determine the association between surgical lesions of distinct grey and white structures and connections with favorable post-operative seizure outcomes.Methods:Patients with drug-resistant temporal lobe epilepsy (TLE) from three epilepsy centers were included. We employed a voxel-based and connectome-based mapping approach to determine the association between favorable outcomes and surgery-induced temporal lesions. Analyses were conducted controlling for multiple confounders, including total surgical resection/ablation volume, hippocampal volumes, side of surgery, and site where the patient was treated.Results:The cohort included 113 patients with TLE [54 women; 86 right-handed; 16.5 (SD = 11.9) age at seizure onset, 54.9% left] who were 61.1% free of disabling seizures (Engel class 1) at follow-up. Postoperative seizure freedom in TLE was associated with 1) surgical lesions that targeted the hippocampus as well as the amygdala-piriform cortex complex and entorhinal cortices; 2) disconnection of temporal, frontal, and limbic regions through loss of white matter tracts within the uncinate fasciculus, anterior commissure, and fornix; and 3) functional disconnection of the frontal (superior and middle frontal gyri, orbitofrontal region) and temporal (superior and middle pole) lobes.Conclusions:Better postoperative seizure freedom are associated with surgical lesions of specific structures and connections throughout the temporal lobes. These findings shed light on the key components of epileptogenic networks in TLE and constitute a promising source of new evidence for future improvements in surgical interventions.Classification of Evidence:This study provides Class II evidence that for patients with temporal lobe epilepsy, postoperative seizure freedom is associated with surgical lesions of specific temporal lobe structures and connections.

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Tumor-Associated Epilepsy in Patients With Brain Metastases: Necrosis-to-Tumor Ratio Forecasts Postoperative Seizure Freedom

10.21203/rs.3.rs-241560/v1 ◽

2021 ◽

Author(s):

Majd Bahna ◽

Muriel Heimann ◽

Christian Bode ◽

Valeri Borger ◽

Lars Eichhorn ◽

...

Keyword(s):

Risk Factors ◽

Brain Metastases ◽

Volume Ratio ◽

Seizure Outcome ◽

Seizure Freedom ◽

Treatment Regimes ◽

Related Quality ◽

Health Related ◽

Neurosurgical Treatment ◽

Postoperative Seizure

Abstract Surgical resection is highly effective in the treatment of tumor-related epilepsy (TRE) in patients with brain metastases (BM). Nevertheless, some patients suffer from postoperative persistent epilepsy which negatively impacts health-related quality of life. Therefore, early identification of patients with potentially unfavorable seizure outcome after BM resection is important. Patients with TRE that had undergone surgery for BM at the authors’ institution between 2013 and 2018 and were analyzed with regard to preoperatively identifiable risk factors for unfavorable seizure outcome. Tumor tissue and tumor necrosis ratios were assessed volumetrically. According to the classification of the International League Against Epilepsy (ILAE), seizure outcome was categorized as favorable (ILAE 1) and unfavorable (ILAE 2 - 6) after 3 months in order to avoid potential interference with adjuvant cancer treatment.Among all 38 patients undergoing neurosurgical treatment for BM with concomitant TRE, 34 patients achieved a favorable seizure outcome (90%). Unfavorable seizure outcome was significantly associated with larger tumor volumes (p=0.012), a midline shift > 7 mm (p=0.025), and a necrosis/tumor volume ratio > 0.2 (p=0.047).The present study identifies preoperatively collectable risk factors for unfavorable seizure outcome in patients with BM and TRE. This might enable to preselect for highly vulnerable patients with postoperative persistent epilepsy who might benefit from accompanying neuro-oncological expertise during further systemical treatment regimes.

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Frameless robot-assisted stereoelectroencephalography in children: technical aspects and comparison with Talairach frame technique

Journal of Neurosurgery Pediatrics ◽

10.3171/2018.1.peds17435 ◽

2018 ◽

Vol 22 (1) ◽

pp. 37-46 ◽

Cited By ~ 24

Author(s):

Taylor J. Abel ◽

René Varela Osorio ◽

Ricardo Amorim-Leite ◽

Francois Mathieu ◽

Philippe Kahane ◽

...

Keyword(s):

Effective Means ◽

Operating Time ◽

Seizure Freedom ◽

Epileptogenic Zone ◽

Complication Rates ◽

Class Iii ◽

Intracranial Hemorrhages ◽

Robot Assisted ◽

Pharmacoresistant Epilepsy ◽

Electrode Implantation

OBJECTIVERobot-assisted stereoelectroencephalography (SEEG) is gaining popularity as a technique for localization of the epileptogenic zone (EZ) in children with pharmacoresistant epilepsy. Here, the authors describe their frameless robot-assisted SEEG technique and report preliminary outcomes and relative complications in children as compared to results with the Talairach frame–based SEEG technique.METHODSThe authors retrospectively analyzed the results of 19 robot-assisted SEEG electrode implantations in 17 consecutive children (age < 17 years) with pharmacoresistant epilepsy, and compared these results to 19 preceding SEEG electrode implantations in 18 children who underwent the traditional Talairach frame–based SEEG electrode implantation. The primary end points were seizure-freedom rates, operating time, and complication rates.RESULTSSeventeen children (age < 17 years) underwent a total of 19 robot-assisted SEEG electrode implantations. In total, 265 electrodes were implanted. Twelve children went on to have EZ resection: 4 demonstrated Engel class I outcomes, whereas 2 had Engel class II outcomes, and 6 had Engel class III–IV outcomes. Of the 5 patients who did not have resection, 2 underwent thermocoagulation. One child reported transient paresthesia associated with 2 small subdural hematomas, and 3 other children had minor asymptomatic intracranial hemorrhages. There were no differences in complication rates, rates of resective epilepsy surgery, or seizure freedom rates between this cohort and the preceding 18 children who underwent Talairach frame–based SEEG. The frameless robot-assisted technique was associated with shorter operating time (p < 0.05).CONCLUSIONSFrameless robot-assisted SEEG is a safe and effective means of identifying the EZ in children with pharmacoresistant partial epilepsy. Robot-assisted SEEG is faster than the Talairach frame–based method, and has equivalent safety and efficacy. The former, furthermore, facilitates more electrode trajectory possibilities, which may improve the localization of epileptic networks.

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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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Robot-assisted stereoelectroencephalography in children

Journal of Neurosurgery Pediatrics ◽

10.3171/2018.7.peds18305 ◽

2019 ◽

Vol 23 (3) ◽

pp. 288-296 ◽

Cited By ~ 3

Author(s):

Robert A. McGovern ◽

Elia Pestana Knight ◽

Ajay Gupta ◽

Ahsan N. V. Moosa ◽

Elaine Wyllie ◽

...

Keyword(s):

Proportional Hazards Model ◽

Refractory Epilepsy ◽

Cox Proportional Hazards Model ◽

Older Age ◽

Hospital Length Of Stay ◽

Seizure Freedom ◽

Epileptogenic Zone ◽

Robot Assisted ◽

Resective Surgery ◽

Medically Refractory Epilepsy

OBJECTIVEThe goal in the study was to describe the clinical outcomes associated with robot-assisted stereoelectroencephalography (SEEG) in children.METHODSThe authors performed a retrospective, single-center study in consecutive children with medically refractory epilepsy who were undergoing robot-assisted SEEG. Kaplan-Meier survival analysis was used to calculate the probability of seizure freedom. Both univariate and multivariate methods were used to analyze the preoperative and operative factors associated with seizure freedom.RESULTSFifty-seven children underwent a total of 64 robot-assisted procedures. The patients’ mean age was 12 years, an average of 6.4 antiepileptic drugs (AEDs) per patient had failed prior to implantation, and in 56% of the patients the disease was considered nonlesional. On average, children had 12.4 electrodes placed per implantation, with an implantation time of 9.6 minutes per electrode and a 10-day postoperative stay. SEEG analysis yielded a definable epileptogenic zone in 51 (89%) patients; 42 (74%) patients underwent surgery, half of whom were seizure free at last follow-up, 19.6 months from resection. In a multivariate generalized linear model, resective surgery, older age, and shorter SEEG-related hospital length of stay were associated with seizure freedom. In a Cox proportional hazards model including only the children who underwent resective surgery, older age was the only significant factor associated with seizure freedom. Complications related to bleeding were the major contributors to morbidity. One patient (1.5%) had a symptomatic hemorrhage resulting in a permanent neurological deficit.CONCLUSIONSThe authors report one of the largest pediatric-specific SEEG series demonstrating that the modern surgical management of medically refractory epilepsy in children can lead to seizure freedom in many patients, while also highlighting the challenges posed by this difficult patient population.

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Stereoelectroencephalography in Children and Adolescents With Difficult-to-Localize Refractory Focal Epilepsy

Neurosurgery ◽

10.1227/neu.0000000000000453 ◽

2014 ◽

Vol 75 (3) ◽

pp. 258-268 ◽

Cited By ~ 50

Author(s):

Jorge Gonzalez-Martinez ◽

Jeffrey Mullin ◽

Juan Bulacio ◽

Ajay Gupta ◽

Rei Enatsu ◽

...

Keyword(s):

Children And Adolescents ◽

Pediatric Patients ◽

Focal Epilepsy ◽

Early Experience ◽

Morbidity Rate ◽

Seizure Outcome ◽

Seizure Freedom ◽

Epileptogenic Zone ◽

Eloquent Cortex

Abstract BACKGROUND: Although stereoelectroencephalography (SEEG) has been shown to be a valuable tool for preoperative decision making in focal epilepsy, there are few reports addressing the utility and safety of SEEG methodology applied to children and adolescents. OBJECTIVE: To present the results of our early experience using SEEG in pediatric patients with difficult-to-localize epilepsy who were not considered candidates for subdural grid evaluation. METHODS: Thirty children and adolescents with the diagnosis of medically refractory focal epilepsy (not considered ideal candidates for subdural grids and strip placement) underwent SEEG implantation. Demographics, electrophysiological localization of the hypothetical epileptogenic zone, complications, and seizure outcome after resections were analyzed. RESULTS: Eighteen patients (60%) underwent resections after SEEG implantations. In patients who did not undergo resections (12 patients), reasons included failure to localize the epileptogenic zone (4 patients); multifocal epileptogenic zone (4 patients); epileptogenic zone located in eloquent cortex, preventing resection (3 patients); and improvement in seizures after the implantation (1 patient). In patients who subsequently underwent resections, 10 patients (55.5%) were seizure free (Engel class I) and 5 patients (27.7%) experienced seizure improvement (Engel class II or III) at the end of the follow-up period (mean, 25.9 months; range, 12 to 47 months). The complication rate in SEEG implantations was 3%. CONCLUSION: The SEEG methodology is safe and should be considered in children/adolescents with difficult-to-localize epilepsy. When applied to highly complex and difficult-to-localize pediatric patients, SEEG may provide an additional opportunity for seizure freedom in association with a low morbidity rate.

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Seizure Outcomes in Patients With Surgically Treated Cerebral Arteriovenous Malformations

Neurosurgery ◽

10.1227/neu.0000000000000919 ◽

2015 ◽

Vol 77 (5) ◽

pp. 762-768 ◽

Cited By ~ 16

Author(s):

Christian von der Brelie ◽

Matthias Simon ◽

Jonas Esche ◽

Johannes Schramm ◽

Azize Boström

Keyword(s):

Life Quality ◽

Seizure Outcome ◽

Seizure Freedom ◽

Common Symptom ◽

Extensive Resection ◽

Chronic Epilepsy ◽

Epilepsy Classification ◽

Drug Resistant Epilepsy ◽

Postoperative Seizure

Abstract BACKGROUND: Epilepsy is the second most common symptom in cerebral arteriovenous malformation (AVM) patients. The consecutive reduction of life quality is a clinically underrated problem because treatment usually focuses on the prevention of intracerebral hemorrhage. OBJECTIVE: To evaluate postoperative seizure outcome with the aim of more accurate counseling for postoperative seizure outcome. METHODS: From 1985 to 2012, 293 patients with an AVM were surgically treated by J.S. One hundred twenty-six patients with preoperative seizures or epilepsy could be identified; 103 of 126 had a follow-up of at least 12 months and were included in the analysis. The different epilepsy subtypes were categorized (sporadic seizures, chronic epilepsy, drug-resistant epilepsy [DRE]). Preoperative workup and surgical technique were evaluated. Seizure outcome was analyzed by using International League Against Epilepsy classification. RESULTS: Sporadic seizures were identified in 41% of patients (chronic epilepsy and DRE were identified in 36% and 23%, respectively). Detailed preoperative epileptological workup was done in 13%. Seizure freedom was achieved in 77% (79% at 5 years, 84% at 10 years). Outcome was significantly poorer in DRE cases. More extensive resection was performed in 11 cases with longstanding symptoms (>24 months) and resulted in better seizure outcome as well as the short duration of preoperative seizure history. CONCLUSION: Patients presenting with AVM-associated epilepsy have a favorable seizure outcome after surgical treatment. Long-standing epilepsy and the progress into DRE markedly deteriorate the chances to obtain seizure freedom and should be considered an early factor in establishing the indication for AVM removal.

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