Seizure Outcome in Patients Undergoing Temporal Lobe Resections for Epilepsy

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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De novo temporal intermittent rhythmic delta activity after laser interstitial thermal therapy for mesial temporal lobe epilepsy predicts poor seizure outcome

Clinical Neurophysiology ◽

10.1016/j.clinph.2018.11.012 ◽

2019 ◽

Vol 130 (1) ◽

pp. 122-127 ◽

Cited By ~ 3

Author(s):

William O. Tatum ◽

Neeharika Thottempudi ◽

Vivek Gupta ◽

Anteneh M. Feyissa ◽

Sanjeet S. Grewal ◽

...

Keyword(s):

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

De Novo ◽

Mesial Temporal Lobe Epilepsy ◽

Thermal Therapy ◽

Seizure Outcome ◽

Laser Interstitial Thermal Therapy ◽

Delta Activity ◽

Mesial Temporal Lobe ◽

Rhythmic Delta Activity

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The role of presurgical EEG parameters and of reoperation for seizure outcome in temporal lobe epilepsy

Seizure ◽

10.1016/j.seizure.2017.08.015 ◽

2017 ◽

Vol 51 ◽

pp. 174-179 ◽

Cited By ~ 7

Author(s):

B. Schmeiser ◽

J. Zentner ◽

B.J. Steinhoff ◽

A. Brandt ◽

A. Schulze-Bonhage ◽

...

Keyword(s):

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Seizure Outcome

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Extent of Mesiobasal Resection Determines Outcome after Temporal Lobectomy for Intractable Complex Partial Seizures

Neurosurgery ◽

10.1227/00006123-199107000-00009 ◽

1991 ◽

Vol 29 (1) ◽

pp. 55-61 ◽

Cited By ~ 72

Author(s):

Mohamed H. Nayel ◽

Issam A. Awad ◽

Hans Luders

Keyword(s):

Temporal Lobe ◽

Seizure Frequency ◽

Compartment Model ◽

Extent Of Resection ◽

Temporal Lobectomy ◽

Seizure Outcome ◽

Partial Seizures ◽

Complex Partial Seizures ◽

Lateral Structures

Abstract The extent of resection was assessed in 94 patients who underwent temporal lobectomy for medically intractable complex partial seizures originating from a unilateral seizure focus in the anteromesial temporal lobe. Postoperative magnetic resonance imaging in the coronal plane was used to quantify the extent of resection of lateral and mesiobasal structures according to a 20-compartment model of the temporal lobe. Successful seizure outcome (≥90% reduction in seizure frequency) was accomplished in 83% of the patients (all followed up for more than 1 year; mean duration of follow-up, 25.2 months) and correlated significantly (P<0.05) with the extent of mesiobasal resection, regardless of the extent of resection of lateral structures. Successful seizure outcome was accomplished in 81% of the patients with no structural lesions, and also correlated significantly (P<0.05) with the extent of mesiobasal resection regardless of the extent of lateral resection. A successful seizure outcome was accomplished in 90% of the 21 patients with structural lesions documented by neuroimaging studies. Two patients who underwent extensive lobectomy without resection of the structural lesion had no reduction in seizure frequency postoperatively. We conclude that the most important factor in determining the outcome of temporal lobectomy in patients with unilateral anteromesial temporal lobe epileptogenicity is the extent of resection of structures in the mesiobasal temporal lobe. In patients with structural lesions, lesion resection may be an added contributor to successful seizure outcome. (Neurosurgery 29:55-61, 1991)

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Mesial Temporal Glioma

Pediatric Neurosurgery ◽

10.1093/med/9780190617073.003.0022 ◽

2019 ◽

pp. 199-206

Author(s):

Gerry Grant

Keyword(s):

Temporal Lobe ◽

Single Photon ◽

Photon Emission ◽

Psychosocial Problems ◽

Emission Computed Tomography ◽

Seizure Outcome ◽

Positron Emission ◽

Dystonic Posturing ◽

Operative Planning ◽

Temporal Lobe Seizure

A patient with classic temporal lobe seizure semiology may present with aura, automatisms, and dystonic posturing. Video-electroencephalography (EEG) may identify the ictal onset and magnetoencephalography may further elucidate the anatomy of a temporal lobe abnormality, EEG dipoles, epileptogenic spike sources, and eloquent areas of language or motor function. Structural imaging of the temporal lobe with magnet resonance imaging (MRI) should also be obtained, as well as functional and metabolic imaging such as a subtraction single-photon emission computed tomography (SPECT) and interictal positron emission tomography (PET). Early surgery should be considered in pediatric patients for seizure control, to minimize the adverse effects of anti-epileptic drugs, maximize the child’s developmental potential, and reduce behavioral, cognitive and psychosocial problems. Intraoperative stereotactic navigation and electrocorticography (ECoG) can guide resection. Careful pre-operative planning for correct extent of surgery is key to the best possible seizure outcome.

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Characterization of postsurgical functional connectivity changes in temporal lobe epilepsy

Journal of Neurosurgery ◽

10.3171/2019.3.jns19350 ◽

2020 ◽

Vol 133 (2) ◽

pp. 392-402 ◽

Cited By ~ 3

Author(s):

Victoria L. Morgan ◽

Baxter P. Rogers ◽

Hernán F. J. González ◽

Sarah E. Goodale ◽

Dario J. Englot

Keyword(s):

Functional Connectivity ◽

Temporal Lobe ◽

Network Connectivity ◽

Temporal Lobectomy ◽

Seizure Outcome ◽

Seizure Recurrence ◽

Female Age ◽

Selective Amygdalohippocampectomy ◽

The Brain

OBJECTIVESeizure outcome after mesial temporal lobe epilepsy (mTLE) surgery is complex and diverse, even across patients with homogeneous presurgical clinical profiles. The authors hypothesized that this is due in part to variations in network connectivity across the brain before and after surgery. Although presurgical network connectivity has been previously characterized in these patients, the objective of this study was to characterize presurgical to postsurgical functional network connectivity changes across the brain after mTLE surgery.METHODSTwenty patients with drug-refractory unilateral mTLE (5 left side, 10 female, age 39.3 ± 13.5 years) who underwent either selective amygdalohippocampectomy (n = 13) or temporal lobectomy (n = 7) were included in the study. Presurgical and postsurgical (36.6 ± 14.3 months after surgery) functional connectivity (FC) was measured with 3-T MRI and compared with findings in age-matched healthy controls (n = 44, 21 female, age 39.3 ± 14.3 years). Postsurgical connectivity changes were then related to seizure outcome, type of surgery, and presurgical disease parameters.RESULTSThe results demonstrated significant decreases of FC from control group values across the brain after surgery that were not present before surgery, including many contralateral hippocampal connections distal to the surgical site. Postsurgical impairment of contralateral precuneus to ipsilateral occipital connectivity was associated with seizure recurrence. Presurgical impairment of the contralateral precuneus to contralateral temporal lobe connectivity was associated with those who underwent selective amygdalohippocampectomy compared to those who had temporal lobectomy. Finally, changes in thalamic connectivity after surgery were linearly related to duration of epilepsy and frequency of consciousness-impairing seizures prior to surgery.CONCLUSIONSThe widespread contralateral hippocampal FC changes after surgery may be a reflection of an ongoing epileptogenic progression that has been altered by the surgery, rather than a direct result of the surgery itself. This network evolution may contribute to long-term seizure outcome. Therefore, the combination of presurgical network mapping with the understanding of the dynamic effects of surgery on the networks may ultimately be used to create predictors of the likelihood of long-term seizure recurrence in individual patients after mTLE surgery.

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Reassessing the impact of intraoperative electrocorticography on postoperative outcome of patients undergoing standard temporal lobectomy for MRI-negative temporal lobe epilepsy

Journal of Neurosurgery ◽

10.3171/2018.11.jns182124 ◽

2020 ◽

Vol 132 (2) ◽

pp. 605-614 ◽

Cited By ~ 3

Author(s):

Sanjeet S. Grewal ◽

Mohammed Ali Alvi ◽

William J. Perkins ◽

Gregory D. Cascino ◽

Jeffrey W. Britton ◽

...

Keyword(s):

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Univariate Analysis ◽

Temporal Lobectomy ◽

Seizure Outcome ◽

Incomplete Resection ◽

Seizure Recurrence ◽

Cox Regression Analysis ◽

Epileptiform Discharges ◽

The Impact

OBJECTIVEAlmost 30% of the patients with suspected temporal lobe epilepsy (TLE) have normal results on MRI. Success rates for resection of MRI-negative TLE are less favorable, ranging from 36% to 76%. Herein the authors describe the impact of intraoperative electrocorticography (ECoG) augmented by opioid activation and its effect on postoperative seizure outcome.METHODSAdult and pediatric patients with medically resistant MRI-negative TLE who underwent standardized ECoG at the time of their elective anterior temporal lobectomy (ATL) with amygdalohippocampectomy between 1990 and 2016 were included in this study. Seizure recurrence comprised the primary outcome of interest and was assessed using Kaplan-Meier and multivariable Cox regression analysis plots based on distribution of interictal epileptiform discharges (IEDs) recorded on scalp electroencephalography, baseline and opioid-induced IEDs on ECoG, and extent of resection.RESULTSOf the 1144 ATLs performed at the authors’ institution between 1990 and 2016, 127 (11.1%) patients (81 females) with MRI-negative TLE were eligible for this study. Patients with complete resection of tissue generating IED recorded on intraoperative ECoG were less likely to have seizure recurrence compared to those with incomplete resection on univariate analysis (p < 0.05). No difference was found in seizure recurrence between patients with bilateral independent IEDs and unilateral IEDs (p = 0.15), presence or absence of opioid-induced epileptiform activation (p = 0.61), or completeness of resection of tissue with opioid-induced IEDs on intraoperative ECoG (p = 0.41).CONCLUSIONSThe authors found that incomplete resection of IED-generating tissue on intraoperative ECoG was associated with an increased chance of seizure recurrence. However, they found that induction of epileptiform activity with intraoperative opioid activation did not provide useful intraoperative data predictive of improving operative results for temporal lobectomy in MRI-negative epilepsy.

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