Outcomes of resective surgery in children and adolescents with focal lesional epilepsy: The experience of a tertiary epilepsy center

ObjectiveThis study aimed to investigate the efficacy of resective surgery in children with focal lesional epilepsy by evaluating the predictive value of pre- and postsurgical factors in terms of seizure freedom.MethodsThis study included 61 children aged between 2 and 18 years who were admitted to the pediatric video-EEG unit for presurgical workup. Each patient was evaluated with a detailed history, video-EEG, neuroimaging, and postsurgical outcomes according to Engel classification to predict postsurgical seizure freedom. All the possible factors including history, etiology, presurgical evaluation, surgical procedures, and postsurgical results were analyzed for their predictive value for postoperative seizure freedom.ResultsOf the 61 patients, 75% were diagnosed as having temporal lobe epilepsy (TLE), and 25% were diagnosed with extra-TLE. Two years after the surgery, 78.6% were seizure-free, of which 89% had TLE, and 50% had extra-TLE (p < 0.05). Patients were more likely to have a favorable outcome for seizure freedom if they had rare seizure frequency, focal EEG findings, and focal seizures; had a temporal epileptogenic zone; or had TLE and hippocampal sclerosis. On the other hand, patients were more likely to have unfavorable results for seizure freedom if they had younger age of seizure onset, frequent seizures before the surgery, a frontal or multilobar epileptogenic zone, secondarily generalized seizures, extra-TLE with frontal lobe surgery, or focal cortical dysplasia.SignificanceResective surgery is one of the most effective treatment methods in children with intractable epilepsy. A history of young age of seizure onset, frequent seizures before surgery, secondarily generalized seizures, a multilobar epileptogenic zone, frontal lobe surgery, and focal cortical dysplasia (FCD) are the most important predictive factors indicating that a patient would continue having seizures after surgery. On the other hand, focal seizure semiologies, temporal lobe localization, and hippocampal sclerosis indicate that a patient would have better results in terms of seizure freedom.     

Preoperative depressive symptoms predict postoperative seizure outcome in temporal and frontal lobe epilepsy

ObjectiveRecent research has pointed to the possibility of a bidirectional relationship between seizure frequency in epilepsy and depressive symptoms. The study described here investigated the relationship between preoperative depressive symptomatology and postoperative seizure outcome in a sample of patients with temporal (TLE) and frontal (FLE) lobe epilepsy.MethodsA retrospective analysis was conducted on the data from 115 eligible patients with TLE (N = 97) and FLE (N = 18) and resections limited to one cortical lobe who were evaluated preoperatively and 1 year after epilepsy surgery with respect to depressive symptoms (Beck Depression Inventory, BDI) and seizure outcome. The latter was assessed in terms of actual total seizure frequency as well as a dichotomous variable (seizure free vs. not seizure free) for the 1-year outcome. Repeated-measures analyses of variance and regression analyses were applied.ResultsSeizure-free patients had significantly lower BDI scores preoperatively as well as postoperatively than patients who were not seizure free. In the regression analyses, the preoperative BDI score was a significant predictor of postoperative seizure frequency as well as seizure freedom. When only patients with TLE were analyzed, the results for the association between preoperative BDI and postoperative seizure frequency and seizure freedom remained consistent.ConclusionThe present results provide evidence for a statistical bidirectionality of the relationship between depressive symptoms and postoperative seizure status in a mixed sample of patients with TLE and FLE. Possible reasons for this bidirectional association include an underlying common pathology in both depression and epilepsy, for example, structural changes or functional alterations in neurotransmitter systems.     

Predictive value of electrically induced seizures for postsurgical seizure outcome

ObjectiveTo determine whether semiological similarity of electrically induced seizures (EIS) and spontaneously occurring habitual seizures (SHS) is associated with postsurgical seizure outcome in patients undergoing invasive video-EEG monitoring (VEM) before resective epilepsy surgery.MethodsData of patients undergoing invasive VEM were retrospectively reviewed and included if at least one EIS and SHS during VEM occurred and the brain region in which EIS were elicited was resected. Seizure outcome was evaluated at three follow-up (FU) visits after surgery (1, 2 years and last available FU) according to the classification by Engel and the International League Against Epilepsy (ILAE). The level of semiological similarity of EIS and SHS was rated blinded to the surgical outcome. Statistics were done using Fisher’s exact test and a mixed linear-logistic regression model.Results65 patients were included. Postsurgical seizure freedom was achieved in 51% (ILAE class 1) and 58% (Engel class I) at last FU (median 36 months). Patients with identical EIS and SHS displayed significantly better postsurgical seizure outcomes (ILAE class 1 at last FU: 76% vs. 31%, p < 0.001; Engel class I: 83% vs. 39%, p < 0.001).ConclusionEIS are useful to confirm the location of the epileptogenic zone. A high level of similarity between EIS and SHS is associated with a favorable postsurgical seizure outcome.SignificanceEIS may be used as an additional predictor of postsurgical outcome when counselling patients to proceed to resective epilepsy surgery.     

Postsurgical outcome in patients with auditory auras and drug-resistant epilepsy

PurposeWe assessed whether patients with auditory auras have similar outcomes after epilepsy surgery as patients without auditory auras, and hypothesized that patients with non-dominant hemisphere foci might fare better after temporal lobe surgery than patients with dominant resections.MethodsIn this retrospective study, outcome after temporal resection was assessed for patients with drug-resistant epilepsy. Preoperative demographic data, clinical data, and surgical outcome were prospectively registered in a database from 1986 through 2016. Seizure outcome was classified as either seizure-free or relapsed.ResultsData were available in 1186 patients. Forty five patients (3.8%) reported auditory auras; 42 patients (93%) had temporal lobe epilepsy (TLE), and three patients (7%) had extratemporal epilepsy. Since most patients with auditory auras had TLE and in order to have comparable groups, we selected 41 patients with auditory auras and compared them with patients without auditory auras who had temporal lobe resections (767 patients). There were no significant demographic or clinical differences between TLE patients with auditory auras and those without. Patients who had auditory auras were more likely to relapse after temporal lobe surgery than those without (p = 0.03). Among patients who had auditory auras and temporal lobe surgery, side of surgery was not related to postoperative outcome (p = 0.3).ConclusionAuditory auras are rare among patients with drug-resistant TLE. The presence of an auditory aura in a patient with drug-resistant TLE carries a worse prognosis for a postoperative seizure free outcome and this is not related to the side of surgery.     

Major depressive disorder as a predictor of a worse seizure outcome one year after surgery in patients with temporal lobe epilepsy and mesial temporal sclerosis

PurposeThe association between pre-surgical psychiatric disorders (PDs) and worse seizure outcome in patients with refractory epilepsy submitted to surgery has been increasingly recognized in the literature. The present study aimed to verify the impact of pre- and post-surgical PD on seizure outcome in a series of patients with refractory temporal lobe epilepsy and mesial temporal sclerosis (TLE–MTS).MethodData from 115 TLE–MTS patients (65 females; 56.5%) who underwent cortico-amygdalohippocampectomy (CAH) were analyzed. Pre- and post-surgical psychiatric evaluations were performed using DSM-IV and ILAE criteria. The outcome subcategory Engel IA was considered as corresponding to a favorable prognosis. A multivariate logistic regression model was applied to identify possible risk factors associated with a worse seizure outcome.ResultsPre-surgical PDs, particularly major depressive disorder (MDD), anxiety and psychotic disorders, were common, being found in 47 patients (40.8%). Fifty-six patients (48.7%) were classified as having achieved an Engel IA one year after CAH. According to the logistic regression model, the presence of pre-surgical MDD (OR = 5.23; p = 0.003) appeared as the most important risk factor associated with a non-favorable seizure outcome.ConclusionAlthough epilepsy surgery may be the best treatment option for patients with refractory TLE–MTS, our findings emphasize the importance of performing a detailed psychiatric examination as part of the pre-surgical evaluation protocol.     

Long term outcome of functional hemispherectomy for refractory epilepsy: Experience from a single center

BackgroundHemispherectomy has an established role as a treatment of last resort in patients with unilateral hemispheric lesions suffering from refractory epilepsy.MethodsSeven patients were evaluated at our Epilepsy Unit. We compared the seizure outcome at 6 months, 1, 2, 5 years post-surgery, as well as at end follow-up (mean 7.1 years) using Engel classification. Reduction of antiepileptic drugs (AEDs) was also assessed utilizing equal time frames.ResultsThe mean age of seizure onset was 5.4 years. Engel I was achieved in 5 patients at 6 months (71.4%). Engel at 1 year was predicted by the Engel at 6 months (p = 0.013) with a similar number of patients being classified as Engel I outcome. Engel at 2 years was also predicted by Engel at 6 months and at 1 year (p = 0.030). At end follow-up only 3 patients (42.9%) remained categorized as Engel I outcome. There was a trend toward a stability in Engel classification. All patients with developmental causes for their epilepsy experienced some deterioration of the surgical outcomes. Conversely, all patients with acquired causes were stable throughout follow-up. Seizure outcome at 6 months was worse in the patients who had post-op complications (p = 0.044). Adult and pediatric populations did not differ significantly in any tested variable.ConclusionsHemispherectomy is a valuable resource for seizure control in properly selected patients. Engel patient's evolution could be predicted at 6 months interval. Hemispherectomy could be considered a useful attitude in difficult cases.     

Temporal lobe surgery in medically refractory epilepsy: A comparison between populations based on MRI findings

IntroductionHigh resolution MRI findings suggestive of mesial temporal sclerosis (MRI-MTS) correlate with good outcome after surgery. However, a large group of patients present with normal brain MRI (N-MRI) and temporal lobe epilepsy (TLE). We aim to compare pre-operative ictal EEG patterns in predicting surgical outcomes in the population with MRI-MTS vs. N-MRI after selective anterior-mesial temporal lobe (AMTL) resection.Methods241 patients with unilateral anterior ictal EEG findings underwent selective AMTL resection. 143 MRI-MTS and 98 N-MRI patients were identified. Outcome was based on the modified Engel classification, ictal EEG pattern at seizure onset, demographics and MRI findings.ResultsSeizure-free outcome was seen in the MRI-MTS in 79% of patients, compared to 59.1% (p < .005) of the N-MRI group. No significant difference was identified in ictal EEG patterns at presentation between groups. Class I outcome was achieved in 78.9% of patients that had theta rhythm and MRI-MTS compared to 57.9% of patients that had theta rhythm and N-MRI (p < 0.05).Discussion and conclusionSurgical treatment for mesial TLE is effective. Positive MRI suggestive of mesial temporal sclerosis (MTS) predicts better seizure control after surgery. Theta rhythm is the most common ictal pattern and seems to carry the best prognosis for TLE. However, a well-selected group of patients with N-MRI will benefit from surgical intervention, and similar outcome to MRI-MTS patients can be achieved if delta ictal EEG pattern is presented at initial onset. Early referral to an epilepsy center cannot be emphasized enough, even in situations when high-resolution brain MRI is normal.     

"MRI-negative PET-positive" temporal lobe epilepsy: invasive EEG findings, histopathology, and postoperative outcomes

The aim of this retrospective study was to analyze invasive EEG findings, histopathology, and postoperative outcomes in patients with MRI-negative, PET-positive temporal lobe epilepsy (TLE) (MRI–/PET + TLE) who had undergone epilepsy surgery. We identified 20 patients with MRI-/PET + TLE (8.4% of all patients with TLE who had undergone surgery; 11 men, 9 women). Of the 20 patients, 16 underwent invasive EEG. The temporal pole and hippocampus were involved in the seizure onset zone in 62.5% of the patients. We did not identify a lateral temporal or extratemporal seizure onset in any patient. Of the 20 patients, 17 had follow-up periods > 1 year (mean follow-up = 3.3 years). At the final follow-up, 70.6% patients were classified as Engel I, 5.8% of patients as Engel II, and 11.8% of patients as Engel III and IV (11.8%). Histopathological evaluation showed no structural pathology in any resected hippocampus in 58% of all evaluated temporal poles. The most common pathology of the temporal pole was focal cortical dysplasia type IA or IB. MRI–/PET + TLE should be delineated from other “nonlesional TLE.” The ictal onset in these patients was in each case in the temporal pole or hippocampus, rather than in the lateral temporal neocortex. Standard surgery produced a good postoperative outcome, comparable to that for patients with lesional TLE. Histopathological findings were limited: the most common pathology was focal cortical dysplasia type I.     

Psychogenic nonepileptic seizures in patients with surgically treated temporal lobe epilepsy: Presurgical and de novo postsurgical occurrence

Whether occurring before or after an epilepsy surgery, psychogenic nonepileptic seizures (PNES) impact treatment options and quality of life of patients with epilepsy. We investigated the frequency of pre- and postsurgical PNES, and the postsurgical Engel and psychiatric outcomes in patients with drug-resistant temporal lobe epilepsy (TLE). We reviewed 278 patients with mean age at surgery of 37.1 ± 12.4 years. Postsurgical follow-up information was available in 220 patients, with average follow-up of 4 years.Nine patients (9/278 or 3.2%) had presurgical documented PNES. Eight patients (8/220 or 3.6%) developed de novo PNES after surgery. Pre- and postsurgery psychiatric comorbidities were similar to the patients without PNES. After surgery, in the group with presurgical PNES, five patients were seizure-free, and three presented persistent PNES. In the group with de novo postsurgery PNES, 62.5% had Engel II–IV, and 37.5% had Engel I. All presented PNES at last follow-up.Presurgical video-EEG monitoring is crucial in the diagnosis of coexisting PNES. Patients presenting presurgical PNES and drug-resistant TLE should not be denied surgery based on this comorbidity, as they can have good postsurgical epilepsy and psychiatric outcomes. Psychogenic nonepileptic seizures may appear after TLE surgery in a low but noteworthy proportion of patients regardless of the Engel outcome.     

The relevance of somatosensory auras in refractory temporal lobe epilepsies

The purpose of this study is to look at the prevalence, characteristics, and prognostic value of somatosensory auras (SSAs) in patients who have undergone temporal lobe epilepsy (TLE) surgery to treat drug‐resistant focal epilepsy. We retrospectively reviewed all patients with drug‐resistant epilepsy who underwent TLE surgery at Cleveland Clinic between 2005 and 2010 (n = 333) to study the prevalence, characteristics, and prognostic implications of SSA in the context of TLE surgery. Analyses were performed using two seizure outcome definitions: complete seizure freedom and Engel classification. Of the 333 patients, 26 (7.8%) had SSA. Almost half (12 patients) had unilateral sensory symptoms, whereas the rest had bilateral symptoms. Tingling and numbness were the most frequently reported sensations. Compared to their non‐SSA counterparts, patients with SSA had the same clinical and imaging characteristics, but had a higher rate of breakthrough seizures (p = 0.03), although most (54%) were still able to achieve Engel class of I (p = 0.02). Based on our results we would encourage detailed presurgical testing, which may include an invasive evaluation to analyze the extent of the epileptogenic zone in patients with SSA and suspected TLE.     

Postsurgical outcome in patients with olfactory auras and drug-resistant epilepsy

ObjectivesWe investigated the clinical features associated with olfactory auras in patients with drug-resistant epilepsy and also hypothesized that this type of aura may predict worse postsurgical outcome in patients with drug-resistant temporal lobe epilepsy (TLE).MethodsIn this retrospective analysis, data from all patients with drug-resistant epilepsy who underwent epilepsy surgery were reviewed. Patients were prospectively registered in a database from 1986 through 2016. We assessed outcome in the first 5 years after surgery to produce a Kaplan–Meier estimate of seizure recurrence. Post-surgical outcome was classified into two groups; 1) seizure-free, with or without auras; or 2) relapse of complex partial or secondarily generalized seizures. We also investigated the clinical features of patients with TLE and olfactory auras compared with those without olfactory auras.ResultsWe studied 1186 patients. Thirty-seven patients (3.1%) reported olfactory auras with their seizures. Thirty-two patients had temporal lobe surgery. Intracranial video-EEG recording was performed in four patients. Three patients with lateral temporal neocortical seizures reported olfactory auras with their seizures; two of them were seizure-free after surgery. There were no significant clinical differences between patients with TLE and olfactory auras compared with those without. Seizure outcome after surgery was not significantly different between these two groups (p = 0.3; Cox–Mantel test).ConclusionThe rarity of olfactory auras makes it difficult to propose new diagnostic and treatment strategies. A multicenter approach, which can enroll more patients, is needed to devise better therapies for patients with drug-resistant epilepsy and this symptom.     

Delayed complications after Gamma Knife surgery for intractable epilepsy

Despite the controversy concerning the clinical usefulness of Gamma Knife surgery (GKS; Elekta AB, Stockholm, Sweden) for intractable epilepsy, this treatment modality has attracted attention due to its low invasiveness. We report the long-term outcomes of four patients, focusing particularly on the efficacy and complications of GKS. We reviewed the data of four patients with medically intractable epilepsy who underwent GKS between 1998 and 2000 at our hospital. The marginal dose to the 50% isodose line was 24 Gy in one patient and 20 Gy in the remaining three patients. Two of the four patients were treated in the right temporal lobe, one was treated in the left parietal lobe, and one was treated in the right frontal lobe. The mean follow-up was 12.5 years (range 12–14 years). One patient was seizure free (Engel class IA) 24 months after GKS, and two patients failed to show any seizure reduction (Engel class IVA). However, a clear aggravation was evident in one patient (Engel class IVC). All four patients underwent resective surgery due to radiation necrosis (RN) 7, 10, 10 and 12 years after GKS. Three patients were seizure free (Engel class IA), and one was considered to have Engel class IB status following the resective surgery. GKS treatment resulted in insufficient seizure control and carried a significant risk of RN after several years. Drawbacks such as a delay in seizure control and the risk of RN should be considered when the clinical application of this treatment is evaluated.     

Long-term epilepsy surgery outcomes in patients with MRI-negative temporal lobe epilepsy

Purpose: The outcome of surgery in patients with temporal lobe epilepsy (TLE) and normal high‐resolution magnetic resonance imaging (MRI) has been significantly worse than in patients with unilateral hippocampal damage upon MRI. The purpose of this study was to determine the long‐term outcomes of consecutive true MRI‐negative TLE patients who all underwent standardized preoperative evaluation with intracranial electroencephalography (EEG) electrodes. Methods: In this study we present all adult MRI‐negative TLE surgery candidates evaluated between January 1990 and December 2006 at Kuopio Epilepsy Center in Kuopio University Hospital, which provides a national center for epilepsy surgery in Finland. During this period altogether 146 TLE surgery candidates were evaluated with intracranial electrodes, of whom 64 patients with normal high‐resolution MRI were included in this study. Results: Among the 38 patients who finally underwent surgery, at the latest follow‐up (mean 5.8 years), 15 (40%) were free of disabling seizures (Engel class I) and 6 (16%) were seizure‐free (Engel class IA). Twenty‐one (55%) of 38 patients had poor outcomes (Engel class III–IV). Outcomes did not change compared to 12‐month follow‐up. Histopathologic examination failed to reveal any focal pathology in 68% of our MR‐negative cases. Only patients with noncongruent positron emission tomography (PET) results had worse outcomes (p = 0.044). Discussion: Our results suggest that epilepsy surgery outcomes in MRI‐negative TLE patients are comparable with extratemporal epilepsy surgery in general. Seizure outcomes in the long‐term also remain stable. Modern imaging techniques could further improve the postsurgical seizure‐free rate. However, these patients usually require chronic intracranial EEG evaluation to define epileptogenic areas.     

Epilepsy surgery in patients with bilateral temporal lobe seizures: A systematic review

We explored the association between magnetic resonance imaging (MRI) lesion, degree of seizure laterality on intracranial electroencephalography (iEEG), and seizure outcome in patients with ambiguous or presumed bilateral temporal lobe epilepsy (BiTLE) on scalp EEG. We systematically reviewed the literature using Embase and MEDLINE up to May 31, 2012. Patients with bilateral iEEG, temporal lobe surgery, and follow‐up ≥1 year were included. We undertook three separate analyses on patients whose scalp EEG showed ambiguous onset or BiTLE (1) group data of those whose iEEG demonstrated unilateral TLE, (2) group data of those whose iEEG demonstrated BiTLE, (3) individual patient analysis in those with BiTLE for whom iEEG seizure laterality data were provided. Of 1,403 patients with ambiguous or presumed BiTLE on scalp EEG, 1,027 (73%) proved to have unilateral TLE on iEEG and contributed to the first analysis. Of these, 58% had Engel class I and 9% Engel class II outcomes. Of 132 patients in the second analysis (true BiTLE), Engel class I and II outcomes were achieved in 23% and 14%, respectively. Of 41 patients in the third analysis, 66% and 2% had Engel class I and II outcomes, respectively. The median proportion of seizures ipsilateral to the resection on iEEG did not differ between BiTLE patients with Engel class I–II (76%) and Engel III–IV (78%) outcomes (p = 0.87). Patients with ambiguous or independent bitemporal seizure onset on scalp EEG achieved good surgical outcomes. Overall, a significantly higher proportion of patients achieved good outcomes when iEEG showed unilateral TLE (67%) than when it showed true BiTLE (45%). However, the degree of seizure lateralization in those with BiTLE was not associated with seizure outcome, and it has a limited role in selecting the side of surgery.     

Outcome after cortico-amygdalo-hippocampectomy in patients with temporal lobe epilepsy and normal MRI

RationaleWe describe seizure and neuropsychological outcome obtained after CAH in patients with TLE and normal MRI evaluated in the modern imaging era.MethodsForty-five adult consecutive patients with TLE and normal MRI were studied. All patients had neuropsychological testing, interictal and ictal EEG recordings and MRI. They were divided into two groups: Group 1 (n = 18), included patients in whom non-invasive neurophysiological evaluation was lateralizing and Group 2 (n = 27) included patients with non-lateralizing neurophysiological data who were submitted to invasive recordings.ResultsSeventy-seven percent of the Group 1 patients were rated as Engel I; 11% were rated as Engel II and 11% as Engel III. In Group 2, there were 57% of patients seizure-free, 26% in Engel II and 14% in Engel III. Pre-operatively, mean general IQ was 82 and 78 in Groups1 and 2, respectively; post-operatively, mean general IQ was respectively 86 and 71. Some degree of verbal memory decline was noted in all patients submitted to dominant temporal lobe resection in both Groups 1 and 2. At last follow-up visit, 22% of Group 1 and 11% of Group 2 patients were receiving no antiepileptic drugs (AED).ConclusionsOur data showed that patients with TLE and normal MRI could get good surgical results after CAH although 60% of them would need invasive recordings and their results regarding seizure control and cognition were worse than those obtained in patients with MRI defined temporal lobe lesions. Caution should be taken in offering dominant temporal lobe resection to this subset of patients.     

Type of preoperative aura may predict postsurgical outcome in patients with temporal lobe epilepsy and mesial temporal sclerosis

PurposeAs the initial symptoms of epileptic seizures, many types of auras have significant localizing or lateralizing value. In this study, we hypothesized that the type of aura may predict postsurgical outcome in patients with medically refractory temporal lobe epilepsy (TLE) and mesial temporal sclerosis (MTS).MethodsIn this retrospective study, all patients with a clinical diagnosis of medically refractory TLE due to unilateral mesial temporal sclerosis who underwent epilepsy surgery at the Jefferson Comprehensive Epilepsy Center were recruited. Patients were prospectively registered in a database from 1986 through 2014. Postsurgical outcome was classified into two groups: seizure freedom or relapse. Outcome was compared between seven groups of patients according to their preoperative auras.ResultsTwo hundred thirty-seven patients were studied. The chance of becoming free of seizures after surgery in patients with abdominal aura was 65.1%, while in other patients, this was 43.3% (P = 0.01). In two-by-two comparisons, no other significant differences were observed.ConclusionPatients with medically refractory TLE–MTS who reported abdominal auras preceding their seizures fared better postoperatively with regard to seizure control compared with those who did not report auras, which may indicate bitemporal dysfunction, and to patients with other auras, which may indicate a widespread epileptogenic zone in the latter group of patients.     

Postoperative routine EEG correlates with long-term seizure outcome after epilepsy surgery.

We investigated the correlation of interictal epileptiform discharges (IED) in routine EEG 6 and 24 months after epilepsy surgery with regard to long-term seizure outcome. In 148 patients (74% temporal lobe epilepsy (TLE), 26% extratemporal epilepsy) EEG results (IED present or absent) were correlated with the postoperative outcome using the Engel classification 6 and 24 months after resection (PO6m and PO2y, respectively). Self-evaluation was conducted 3 and 5 years after resection (PO3y and PO5y, respectively). Ninety-one patients (62%) were seizure-free 5 years after resection; 88% of them showed no IED in PO6m. Twenty-eight patients (19%) displayed IED in routine EEG 6 months after resection; 61% of them had recurrent seizures at PO5y, whereas of 120 patients without IED only 33% had recurrent seizures at PO5y; p=0.01. Absence of IED in PO6m and PO2y correlated with good outcome: 71% without IED remained seizure-free, whereas only 25% with IED at PO6m and PO2y remained seizure-free; p=0.001. Seizure-free patients (Engel 1) and patients with less favourable outcome (Engel 3-4) at PO6m and PO2y rarely changed categories of outcome during the following years (p<0.001). Half of the patients with favourable seizure reduction (Engel 2) changed to seizure-free (Engel 1) or to a worse outcome category (Engel 3-4). Postoperative routine EEG is a good prognostic instrument for the prediction of long-term seizure outcome, especially for TLE. It predicts the running up and down of fits in patients with rare seizures (Engel 2).     

Intracranial EEG seizure onset patterns in unilateral temporal lobe epilepsy and their relationship to other variables

ObjectiveWe performed a retrospective study to determine the different types of seizure onset patterns (SOP) in invasive EEG (IEEG) in patients with temporal lobe epilepsy (TLE).MethodsWe analyzed a group of 51 patients (158 seizures) with TLE who underwent IEEG. We analyzed the dominant frequency during the first 3 s after the onset of ictal activity. The cut-off value for distinguishing between fast and slow frequencies was 8 Hz. We defined three types of SOPs: (1) fast ictal activity (FIA) – frequency ?8 Hz; (2) slow ictal activity (SIA) – frequency <8 Hz; and (3) attenuation of background activity (AT) – no clear-cut rhythmic activity during the first 3 s associated with changes of IEEG signal (increase of frequency, decrease of amplitude). We tried to find the relationship between different SOP types and surgery outcome, histopathological findings, and SOZ localization.ResultsThe most frequent SOP was FIA, which was present in 67% of patients. More patients with FIA were classified postoperatively as Engel I than those with SIA and AT (85% vs. 31% vs. 0) (P < 0.001). There were no statistically significant differences in the type of SOP, in the histopathological findings, or in the SOZ localization.ConclusionIn patients with refractory TLE, seizure onset frequencies ?8 Hz during the first 3 s of ictal activity are associated with a better surgical outcome than frequencies <8 Hz.SignificanceOur study suggests that very early seizure onset frequencies in IEEG in patients with TLE could be the independent predictive factor for their outcome, regardless of the localization and etiology.     

Long-Term Management of Seizures after Surgical Treatment of Supratentorial Cavernous Malformations : A Retrospective Single Centre Study

ObjectiveSeizure recurrence after the first-ever seizure in patients with a supratentorial cerebral cavernous malformation (CCM) is almost certain, so the diagnosis and treatment of epilepsy is justified. The optimal method of management of these patients is still a matter of debate. The aim of our study was to identify factors associated with postoperative seizure control and assess the surgical morbidity rate. MethodsWe retrospectively analysed 45 consecutive patients with a supratentorial CCM and symptomatic epilepsy in a single centre. Pre- and postoperative epidemiological data, seizure-related patient histories, neuroimaging results, surgery details and outcomes were obtained from hospital medical records. Seizure outcomes were assessed at least 12 months after surgery. ResultsThirty-five patients (77.8%) were seizure free at the long-term follow-up (Engel class I); six (13,3%) had rare, nocturnal seizures (Engel class II); and four (8.9%) showed meaningful improvement (Engel class III). In 15 patients (33%) in the Engel I group; it was possible to discontinue antiepileptic medication. Although there was not statistical significance, our results suggest that patients can benefit from early surgery. No deaths occurred in our study, and mild postoperative neurologic deficits were observed in two patients (4%) at the long-term follow-up. ConclusionSurgical resection of CCMs should be considered in all patients with a supratentorial malformation and epilepsy due to the favourable surgical results in terms of the epileptic seizure control rate and low postoperative morbidity risk, despite the use of different predictors for the seizure outcome.     

Patient satisfaction with temporal lobectomy/selective amygdalohippocampectomy for temporal lobe epilepsy and its relationship with Engel classification and the side of lobectomy

PurposeThe aim of this study was to investigate not only the effectiveness of epilepsy surgery in improving seizure control but also patient satisfaction with the result of the procedure in a sample of patients operated on at a specialized epilepsy unit.MethodsPatients with temporal lobe epilepsy who had undergone epilepsy surgery (temporal lobectomy/amygdalohippocampectomy) were interviewed in a standardized telephone survey about their satisfaction with the results of the surgery. The morbidity of the surgery was also analyzed retrospectively. The initial study population consisted of 6 amygdalohippocampectomy and 102 temporal lobectomy patients and was reduced to a final sample consisting of 4 amygdalohippocampectomy and 67 lobectomy patients, as the other patients were not available for interview. Surgical results were based on the Engel classification, and satisfaction with the surgery was assessed by asking patients to rate their result and state whether they would make the same decision (to be operated on) again.ResultsA significant number of patients classified as Engel I or II, who considered the surgical outcome good or excellent, said they would have the surgery again (p < 0.001). Left temporal lobectomy patients whose results fell in the Engel III/IV bracket were less satisfied (p = 0.001) than right temporal lobectomy patients with the same Engel classifications (0.048). Left temporal lobectomy patients who were classified as Engel class III and IV were less likely to have the surgery again if they had the choice (p = 0.016).DiscussionPatient satisfaction with the results of epilepsy surgery may depend not only on achieving seizure control but also on the temporal lobe resected. Since worse results were associated with lower satisfaction rates only for left temporal resection patients, it is possible that the cognitive consequences of this procedure compound the worse surgical result, leading to decreased satisfaction.