Seizure outcome and hippocampal atrophy in familial mesial temporal lobe epilepsy

OBJECTIVE: To describe the clinical, genetic and MR characteristics of patients with familial mesial temporal lobe epilepsy (MTLE). DESIGN/METHODS: The familial occurrence of MTLE was identified by a systematic search of family history of seizures in patients followed in the authors' epilepsy clinic. All probands and, whenever possible, other affected family members underwent EEG and MR investigations. RESULTS: Twenty-two unrelated families with at least two individuals with MTLE were identified by clinical and EEG findings. Ninety-eight individuals with history of seizures were evaluated. Sixty-eight patients fulfilled the diagnostic criteria for MTLE. MRI was performed in 84 patients, and showed hippocampal atrophy with increased T2 signal in 48 (57%). The distribution of hippocampal atrophy according to the seizure outcome groups was 6 of 13 patients (46%) with seizure remission, 16 of 31 (51%) with good seizure control under medication, and all 16 patients with refractory MTLE. Hippocampal atrophy was found also in patients that did not fulfill the criteria for MTLE: 3 of 10 (30%) patients with febrile seizure alone, 6 of 10 (60%) patients with recurrent generalized tonic-clonic seizures, and 1 of 4 (25%) patients with a single partial seizure. CONCLUSION: Familial MTLE is a clinically heterogeneous syndrome. Hippocampal atrophy was observed in 57% of patients, including those with benign course or seizure remission, indicating that the relationship between hippocampal atrophy and severity of epilepsy might be more complex than previously suspected. In addition, these findings indicate the presence of a strong genetic component determining the development of mesial temporal sclerosis in these families.     

Differences in memory performance and other clinical characteristics in patients with mesial temporal lobe epilepsy with and without hippocampal atrophy

Mesial temporal lobe epilepsy (MTLE) is usually accompanied by memory deficits due to damage to the hippocampal system. In most studies, however, the influence of hippocampal atrophy (HA) is confounded with other variables, such as: type of initial precipitating injury and pathological substrate, effect of lesion (HA) lateralization, history of febrile seizures, status epilepticus, age of seizure onset, duration of epilepsy, seizure frequency, and antiepileptic drugs (AEDs). To investigate the relationship between memory deficits and these variables, we studied 20 patients with MTLE and signs of HA on MRI and 15 MTLE patients with normal high-resolution MRI. The findings indicated that (1) HA, earlier onset of seizures, longer duration of epilepsy, higher seizure frequency, and AEDs (polytherapy) are associated with memory deficits; and (2) there is a close relationship between deficits of verbal memory and left HA, but not between visual memory and right HA.     

Ictal Scalp EEG in Unilateral Mesial Temporal Lobe Epilepsy

Summary: Purpose: We wished to determine the predictive significance of unilateral hippocampal atrophy and interictal spikes on localization of ictal scalp EEG changes and assess whether ictal EEG provides information that might change treatment or influence prognosis in patients with such characteristics of epilepsy.
Methods: We analyzed EEG seizure patterns in 118 seizures in 24 patients with unilateral mesial temporal lobe epilepsy (MTLE) defined by typical clinical seizure semiology, unilateral hippocampal atrophy on magnetic resonance imaging (MRI) and unitemporal spikes on interictal EEG. Two blinded electroencephalographers independently determined morphology, location, and time course of ictal EEG changes.
Results: Lateralization was possible in 88.4–92.0% of seizures and always corresponded to the side of the interictal spike focus and of hippocampal atrophy on MRI. Although only 30.4–33.9% of seizures were lateralized at onset, a later significant pattern emerged (12.6–13.3 s after EEG seizure onset) that allowed lateralization in 82.4–91.O% of seizures with non-lateralized onset. Interobserver reliability for lateralization was excellent, with a K-value of 0.85. In most patients, either all (79.2–83.3%) or >50% (8.3–16.7%) of seizures were lateralized. In only a small proportion of patients (4.2–8.3%) were 40% of seizures lateralized. In 1 patient, no seizure could be lateralized by 1 electroencephalographer. The results of ictal EEG recordings did not alter the surgical approach and did not correlate with surgical outcome.
Conclusions: We conclude that unilateral hippocampal atrophy on MRI and unitemporal interictal spikes can predict localization of ictal scalp EEG changes with a high degree of reliability and that ictal EEG provides no additional localizing information in this particular patient group.     

Relations Between EEG Seizure Morphology, Interhemispheric Spread, and Mesial Temporal Atrophy in Bitemporal Epilepsy

Summary: Purpose: A strong relation exists between lateralization of seizure onset in temporal-lobe epilepsy and atrophic mesial structures measured by volumetric magnetic resonance imaging (MRI). We examined whether this relation extended to subregions of the mesial temporal lobe and whether the trend for seizures to spread contralaterally could be related to the localization of atrophy. Methods: We analyzed 362 seizures (with and without clinical signs) from 23 patients having bitemporal epilepsy in whom intracerebral electrodes were implanted for presurgical evaluation. Patients had measurements of hippocampal and amygdala volumes, including comparison with normal controls. We assessed on EEG the laterialization and localization of seizure onset and the trend to spread to the contralateral side (proportion of seizures that spread for each patient). We included all seizures, independent of the presence of clinical manifestations. These features were related to presence and localization of atrophy. Results: Among the 19 patients with mesial atrophy, agreement between side of prevalent seizure onset and predominant atrophy was found in 10 (53%). From 99 seizures starting in a temporal lobe with atrophy limited to the hippocampus, 67% started simultaneously in amygdala and hippocampus, 20% in hippocampus, and 13% in amygdala. From 137 seizures starting in a temporal lobe with amygdala and hippocampal atrophy, 47% started in amygdala and hippocampus, 48% in hippocampus, and 5% in amygdala. The trend to spread was 45% to the most atrophic side and 62% to the normal or less atrophic side. Conclusions: When examining amygdala and hippocampus in this group of patients with bitemporal epilepsy, regions of seizure onset did not correspond to regions of predominant atrophy. The likelihood that seizures spread contralaterally was not influenced by atrophy in the region targeted by the spread. Precise relation between mesial temporal atrophy and seizures remain to be elucidated.     

Clinical study on temporal lobe epilepsy in childhood caused by temporal lobe space-occupying lesions

We studied the clinicoelectrical and neuroimaging features of 11 patients with symptomatic temporal lobe epilepsy (TLE) caused by temporal lobe space occupying lesions (SOLs), and compared its characteristics with those of 19 mesial TLE (MTLE) patients. Brain MRI demonstrated SOLs in the mesiotemporal lobe in 9, and laterotemporal lobe in the remaining 2 patients. Ten of the 11 patients successfully underwent surgery, which revealed tumors in 7 and focal cortical dysplasia in 3 patients. Comparisons of the clinical features between those with SOTLE and MTLE showed that both conditions shared the same clinical seizure manifestations such as gastric uprising sensation or ictal fear and a favorable response to surgery. However, the patients with SOTLE had fewer febrile convulsion, and more frequent seizure recurrences as well as TLE EEG discharges and associations of the monophasic clinical course than those with MTLE. In addition, the MRI findings were characterized by unilateral hippocampal atrophy in MTLE and expanding or SOLs in the SOTLE group. Children with complex partial seizures of suspected temporal lobe origin should undergo extensive neuroimaging evaluation.     

Association of ipsilateral motor automatisms and contralateral dystonic posturing: a clinical feature differentiating medial from neocortical temporal lobe epilepsy.

BACKGROUND: Clinical features that may help to differentiate medial temporal lobe epilepsy (MTLE) from neocortical temporal lobe epilepsy (NTLE) are lacking. OBJECTIVE: To investigate the localizing and lateralizing value of the association of ipsilateral motor automatisms and contralateral dystonic posturing in patients with medically refractory temporal lobe epilepsy. PATIENTS AND METHODS: Videotapes of 60 patients with well-defined MTLE, NTLE, or both were reviewed to assess the presence and the localizing value of unilateral dystonic posturing associated with motor automatisms. RESULTS: Twenty-eight of the 60 patients exhibited unilateral dystonic posturing. This sign was observed in patients with MTLE and NTLE. It was mostly contralateral to the seizure focus in patients with MTLE and exclusively ipsilateral in patients with NTLE. Unilateral motor automatisms occurred in 26 of the 60 patients with MTLE or NTLE. It was predominantly ipsilateral to the seizure focus in patients with MTLE and exclusively contralateral in patients with NTLE. The association of ipsilateral motor automatisms and contralateral dystonic posturing was found in 14 patients with MTLE but in none of the patients with NTLE. Two patients who had medial and neocortical seizure onset also exhibited this clinical feature. This association was not significantly correlated with the postoperative outcome in patients with MTLE. CONCLUSIONS: The association of ipsilateral motor automatisms and contralateral dystonic posturing may help to differentiate MTLE from NTLE with a reliable lateralizing value. This clinical association may reflect a specific pattern in the spread of the ictal discharge.     

Interictal regional delta slowing is an EEG marker of epileptic network in temporal lobe epilepsy

Purpose: Several studies have suggested that interictal regional delta slowing (IRDS) carries a lateralizing and localizing value similar to interictal spikes and is associated with favorable surgical outcomes in patients with temporal lobe epilepsy (TLE). However, whether IRDS reflects structural dysfunction or underlying epileptic activity remains controversial. The objective of this study is to determine the cortical electroencephalography (EEG) correlates of scalp‐recorded IRDS, in so doing, to further understand its clinical and biologic significances. Methods: We examined the cortical EEG substrates of IRDS with electrocorticography (ECoG‐IRDS) and delineated the spatiotemporal relationship between ECoG‐IRDS and both interictal and ictal discharges by recording simultaneously scalp and intracranial EEG in 18 presurgical candidates with TLE. Key Findings: Our results demonstrated that ECoG‐IRDS is typically a mixture of delta/theta slowing and spike‐wave potentials. ECoG‐IRDS was predominantly recorded from basal and anterolateral temporal cortex, occasionally in mesial, posterior temporal, and extratemporal regions. Abundant IRDS was most commonly observed in patients with neocortical temporal lobe epilepsy (NTLE), whereas infrequent to moderate IRDS was usually observed in patients with mesial temporal lobe epilepsy (MTLE). The anatomic distribution of ECoG‐IRDS was highly correlated with the irritative and seizure‐onset zones in 10 patients with NTLE. However, it was poorly correlated with the irritative and seizure‐onset zones in the 8 patients with MTLE. Significance: These findings demonstrate that IRDS is an EEG marker of epileptic network in patients with TLE. Although IRDS and interictal/ictal discharges likely arise from the same neocortical generator in patients with NTLE, IRDS in patients with MTLE may reflect a network disease that involves temporal neocortex.     

Bilateral mesial temporal lobe epilepsy: comparison of scalp EEG and hippocampal MRI-T2 relaxometry

OBJECTIVE: Bilateral hippocampal abnormality is frequent in mesial temporal lobe sclerosis and might affect outcome in epilepsy surgery. The objective of this study was to compare the lateralization of interictal and ictal scalp EEG with MRI T2 relaxometry. MATERIAL AND METHODS: Forty-nine consecutive patients with intractable mesial temporal lobe epilepsy (MTLE) were studied with scalp EEG/video monitoring and MRI T2 relaxometry. RESULTS: Bilateral prolongation of hippocampal T2 time was significantly associated with following bitemporal scalp EEG changes: (i) in ictal EEG left and right temporal EEG seizure onsets in different seizures, or, after regionalized EEG onset, evolution of an independent ictal EEG over the contralateral temporal lobe (left and right temporal asynchronous frequencies or lateralization switch; P = 0.002); (ii) in interictal EEG both left and right temporal interictal slowing (P = 0.007). Bitemporal T2 changes were not, however, associated with bitemporal interictal epileptiform discharges (IED). Lateralization of bilateral asymmetric or unilateral abnormal T2 findings were associated with initial regionalization of the ictal EEG in all but one patient (P < 0.005), with lateralization of IED in all patients (P < 0.005), and with scalp EEG slowing in 28 (82,4%) of 34 patients (P = 0.007). CONCLUSION: Our data suggest that EEG seizure propagation is more closely related to hippocampal T2 abnormalities than IED. Interictal and ictal scalp EEG, including the recognition of ictal propagation patterns, and MRI T2 relaxometry can help to identify patients with bitemporal damage in MTLE. Further studies are needed to estimate the impact of bilateral EEG and MRI abnormal findings on the surgical outcome.     

Neocortical temporal lobe epilepsy: intracranial EEG features and surgical outcome.

Patients with neocortical temporal lobe epilepsy (NTLE) may have less favorable outcome with anterior temporal lobectomy than those with mesial temporal foci. The authors analyzed ictal intracranial electroencephalograms (EEGs) in patients with NTLE to identify features that predict surgical outcome. The following intracranial ictal EEG features in 31 consecutive medically intractable NTLE patients were studied: Frequency (i.e., low-voltage fast [>20 Hz], recruiting ictal-onset spikes, ictal-onset rhythms less than 5 Hz, ictal-onset rhythms with repetitive sharp waves between 5 and 20 Hz); extent of ictal onset (focal, sublobar, and lobar); localization within the temporal lobe (anterior, posterior, or regional); and the time to seizure spread outside the temporal lobe (rapid, intermediate, and slow). The average follow-up period was 36.7 months (range, 18 to 60 months). Findings between two outcome groups were compared: class I group (seizure-free) and class II to IV group (persistent seizures). Twenty-one (66.7%) of 31 patients with NTLE were seizure-free. Intracranial EEG features which were significantly associated with seizure-free outcome were focal or sublobar onset, anterior temporal onset, and slow propagation time (P < 0.05). There was a trend for patients with ictal onset morphologies of slow ictal-onset rhythm and repetitive sharp waves to be seizure-free (P = 0.07). Intracranial EEG is helpful in predicting surgical outcome in NTLE patients.     

Clinical,semiological, electroencephalographic,and neuropsychological features of “pure” neocortical temporal lobe epilepsy

Aims: We examined the clinical, semiological, scalp EEG, and neuropsychological features of patients with “pure” neocortical temporal lobe epilepsy (NTLE) who were successfully treated by neocortical temporal resection sparing the mesial temporal structures. Methods: This retrospective study included 17 patients with lesional NTLE who satisfied the following criteria: presence of a discrete structural lesion in the lateral temporal lobe on preoperative MRI; lateral temporal resection sparing the mesial temporal structures; follow‐up for at least two years after surgery; and favourable postoperative seizure outcome (Engel Class I). The study included 10 females and seven males, and the age at surgery ranged from 15 to 48 years (mean: 30.7 years). Auras, video‐recorded seizure semiology, interictal and ictal EEG, and pre‐ and post‐operative neuropsychological data were reviewed. Twenty patients with mesial temporal lobe epilepsy (MTLE) with hippocampal sclerosis, who had a favourable postoperative seizure outcome (Engel Class I), were selected as a control group. Results: Age at seizure onset was significantly greater in patients with NTLE than in controls. A history of febrile convulsion was significantly less frequent in NTLE patients. Epigastric ascending sensation (6% versus 40%; p=0.017), oral automatisms (29% versus 80%; p=0.003), gestural automatisms (47% versus 80%; p=0.047), and dystonic posturing (0% versus 40%; p=0.003) were significantly less frequent in NTLE than controls. Ictal unitemporal rhythmic theta activity was also significantly less frequent in NTLE than controls (35.3% versus 75%; p=0.015). Preoperative IQ score (range: 68 to 114; mean: 88.9) and preoperative memory quotient score (range: 56–122; mean: 98.1) were significantly higher in NTLE (p=0.003 and p=0.048, respectively). Conclusion: There were notable differences in clinical, semiological, EEG, and neuropsychological features between “pure” NTLE and MTLE. These findings may be useful to identify the epileptogenic zone.     

Monoamine neurotransmitters in resected hippocampal subparcellations from neocortical and mesial temporal lobe epilepsy patients: in situ microvoltammetric studies

It is known that epilepsy patients diagnosed with neocortical temporal lobe epilepsy (NTLE), differ from those diagnosed with mesial temporal lobe epilepsy (MTLE), e.g., in hippocampal (HPC) pathology. In the present studies, we tested the hypothesis that NTLE and MTLE subtypes of human epilepsy might differ in regards to their HPC monoamine neurochemistry. Monoamine neurotransmitters were studied in separate signals and within s with semiderivative microvoltammetry, used in combination with stearate indicator, Ag-AgCl reference and stainless steel auxiliary microelectrodes. Anterior HPC specimens from the patients' epileptogenic zone, defined by electrocorticography, were resected neurosurgically from 13 consecutive patients with intractable temporal lobe epilepsy. Four patients were diagnosed with NTLE and nine with MTLE. The criteria for the diagnosis of NTLE versus MTLE was absence versus presence of HPC sclerosis, respectively, based on MRI examination of resected tissue. In addition, NTLE patients demonstrated seizure onset in anterolateral temporal neocortex on electroencephalography (EEG). HPC subparcellations studied were: (a) Granular Cells of the Dentate Gyrus (DG), (b) Polymorphic Layer of DG and (c) Pyramidal Layer: subfields, CA1 and CA2. Dopamine (DA), serotonin (5-HT), norepinephrine (NE) and ascorbic acid (AA) (co-factor in DA to NE synthesis), exhibited separate and characteristic half-wave potentials in millivolts. Each half-wave potential, i.e., the potential at which maximum current was generated, was experimentally established in vitro. Concentrations of neurotransmitters found in HPC subparcellations were interpolated from calibration curves derived in vitro from electrochemical detection of monoamines and AA in saline phosphate buffer. Significant differences between subtypes in concentration of monoamines were analyzed by the Mann Whitney rank sum test and those differences in probability distribution of monoamines were analyzed by the Fisher Exact test; in each case, P<0.01 was the criteria selected for determining statistical significance. DA concentrations were higher in NTLE compared with MTLE in each HPC subparcellation [P=0.037, 0.024 and 0.007, respectively (P<0.01)] and DA occurred more frequently in NTLE in the Pyramidal Layer [P=0.077 (P<0.01)]. AA was present in one NTLE patient. NE concentrations were higher in MTLE vs. NTLE in each subparcellation [P=0.012, 0.067 and 0.07, respectively (P<0.01)] and NE occurred more frequently in MTLE in Granular Cells of DG and Pyramidal Layer [P=0.052 and 0.014, respectively (P<0.01)]. In MTLE, NE concentrations in the CA1 subfield of the Pyramidal Layer were decreased vs. the CA2 subfield [P=0.063 (P<0.01)]. Serotonin was found in every HPC subparcellation of each subtype but 5-HT concentrations were higher in NTLE vs. MTLE in the Granular Cells of DG and the Pyramidal Layer (CA1 subfield) [P=0.076 and 0.095, respectively (P<0.01)]. Thus, this preliminary study showed that marked differences in HPC monoamine neurochemistry occurred in NTLE patients as compared with MTLE patients.     

Degree of hippocampal atrophy is not related to a history of febrile seizures in patients with proved hippocampal sclerosis

OBJECTIVES: To examine the degree of hippocampal atrophy in patients with temporal lobe epilepsy and proved hippocampal sclerosis to determine whether or not patients with febrile seizures have more severe hippocampal atrophy. To determine whether or not there is a relation between age of seizure onset, duration of temporal lobe epilepsy, or seizure frequency, and severity of hippocampal atrophy. METHODS: Hippocampal volumes were measured from volumetrically acquired MR images in 77 consecutive surgical patients with temporal lobe epilepsy (37 febrile seizures (FS)+, 40 FS-) with proved hippocampal sclerosis, and compared with 98 controls. RESULTS: Ipsilateral and contralateral hippocampal volumes were not significantly different between the FS+ and FS- groups. There was no difference in the age of onset of habitual seizures, duration of epilepsy, or age at the time of surgery, between these groups. No clinically significant correlations were found between hippocampal volumes and age of onset of first non-febrile seizure, duration of temporal lobe epilepsy, or complex partial and secondarily generalised seizure frequency, in patients with and without febrile seizures. CONCLUSIONS: Although febrile seizures was associated with hippocampal sclerosis in 48% of patients in this surgical series, the degree of MRI determined hippocampal atrophy was not related to a history of such seizures. The results do not support the view that febrile seizures cause more severe hippocampal sclerosis and are consistent with the hypothesis that hippocampal sclerosis is a pre-existing abnormality.     

Clinical implications of scalp ictal EEG pattern in patients with temporal lobe epilepsy

ObjectiveTo determine the clinical implications of scalp ictal EEG pattern in patients with temporal lobe epilepsy (TLE).MethodsScalp EEG ictal patterns were retrospectively determined in 27 consecutive patients with medically refractory temporal lobe epilepsy who underwent phase-1 scalp video-EEG and phase-2 simultaneous scalp and intracranial video-EEG recordings for pre-surgical evaluation.ResultsOf the 192 temporal lobe seizures recorded during phase-1 and phase-2 scalp video-EEG studies, 124 (65%) seizures were associated with theta/alpha (5–9 Hz) ictal onset pattern, and 68 (35%) seizures were associated with delta (2–5 Hz) ictal onset pattern. Fourteen (52%) patients had exclusively theta/alpha ictal onset, 3 (11%) patients had exclusively delta ictal onset, and 10 (37%) patients had mixed theta/alpha and delta ictal onsets. MTLE was observed in 26 patients who had 124 seizures with theta/alpha ictal onset and 59 seizures with delta ictal onset. LTLE was observed in one patient who had 9 seizures with delta ictal onset. Scalp ictal EEG pattern was not significantly correlated with postsurgical seizure outcomes.ConclusionsBoth scalp delta and theta/alpha ictal onset patterns can be commonly found in patients with MTLE.SignificanceScalp delta ictal onset is not a unique EEG pattern for LTLE as commonly believed.     

Unilateral hippocampal sclerosis with contralateral temporal scalp ictal onset

PURPOSE: To investigate the clinical characteristics and surgical outcomes in patients with unilateral hippocampal sclerosis whose scalp ictal EEG recordings localize to the opposite temporal lobe. METHODS: We retrospectively reviewed the data of all adult patients who had undergone depth electrode implantation for suspected temporal lobe epilepsy (TLE) at UCLA (1993-2000) or the Montreal Neurological Institute (1991-1998) to identify patients who had (a) unilateral hippocampal atrophy, and (b) surface ictal recordings in which the majority of seizures appeared to initiate in the opposite temporal lobe, with few or none that were concordant with the hippocampal atrophy. RESULTS: Of 109 patients with suspected TLE who underwent depth electrode study at the two centers, five patients met the aforementioned criteria. Four of these five had very severe hippocampal atrophy, whereas the fifth had mild atrophy but extensive signal change on magnetic resonance imaging (MRI). Depth electrode recordings in four of the five patients yielded clear ictal onset in the mesial temporal lobe ipsilateral to the imaging abnormality (contralateral to apparent scalp ictal onset). One patient had an unusual bitemporal onset pattern, which was nonetheless suggestive of onset in the sclerotic hippocampus. No patient had intracranial ictal onset contralateral to the imaging abnormality. All patients underwent resection of the structurally abnormal temporal lobe. After follow-up of > or = 2 years, four (80%) of five patients were seizure free, while the fifth showed lesser improvement (class III). CONCLUSIONS: Some patients with severe hippocampal sclerosis (sometimes called a "burned-out hippocampus") have atypical spread of ictal discharges, resulting in apparent gross discordance between imaging and scalp ictal recordings. These patients nonetheless have excellent surgical outcomes on the whole. Whether such patients may forego intracranial recordings requires further study.     

Medial temporal lobe epilepsy: gender differences

The present study investigated the gender differences in medial temporal lobe epilepsy (MTLE) with regard to clinical history, seizure semiology, and EEG data. To avoid the influence of pathological and localisation differences, we included only MTLE patients with hippocampal sclerosis. Patients who had long term video EEG recordings with registered seizures and unilateral hippocampal sclerosis proved by high resolution MRI were included. There were 153 patients (86 women and 67 men) who met our inclusion criteria. The mean age of the patients was 33.5 years (range 16-59). The mean age at epilepsy onset was 10.8 years. Although there were more women than men, this difference was not significant (p = 0.15). We found that male patients experienced generalised seizures significantly more often, and isolated auras significantly less often than female patients. Analysing EEG data, we found that a seizure pattern lateralised to the side of the hippocampal sclerosis occurred more often in female patients. In the logistic regression analysis, we found that all three factors were associated independently with gender. Odds ratio (OR) for female gender in patients with generalised seizures was 0.44 (95% confidence interval (95% CI) 0.21 to 0.92; p<0.05). In patients with isolated auras OR for female gender was 2.1 (95% CI 1.1 to 4.2; p<0.05). OR for female gender in patients with lateralised seizure pattern was 8.8 (95% CI 1.8 to 42.7; p<0.01). Men more often had secondarily generalised tonic-clonic seizures, while women had isolated auras and lateralised EEG seizure pattern more often. Our data suggest that the seizure spread is more extended or occurs more frequently in men than in women.     

Surgical treatment for temporal lobe epilepsy in patients over age 50 years]

We retrospectively analyzed 4 patients over age 50 (52 - 57) years with intractable medial temporal lobe epilepsy(MTLE) who underwent the anterior temporal lobectomy with hippocampectomy. Case 1 had MTLE with old brain abscess in the left lateral temporal lobe and Cases 2 - 4 had MTLE with histologically verified hippocampal sclerosis. In Cases 2 - 4, although the onset of seizures occurred 26 to 37 years prior to the time of surgery, there was no mental problem (IQ = 87 - 100). In Cases 1, chronic invasive electrocorticography recording using subdural electrodes was obtained, while in Case 2 - 4, the epileptogenic region was defined by noninvasive preoperative evaluation. Postoperatively, all patients obtained a meaningful improvement, becoming either free from seizures or only experiencing a rare seizure, and returned to work or usual activities without surgical complications. Surgery for MTLE appears to be effective for older individuals and carries a small risk of postoperative complications.     

Nontumoral occipitotemporal epilepsy: localizing findings and surgical outcome

We describe a syndrome of medically intractable occipitotemporal epilepsy of nontumoral developmental origin and its treatment by surgery. From our epilepsy surgery database of 1988 to 1996, we selected all patients without neoplasm who had at least two characteristics localizing to the occipital lobe (clinical symptoms, interictal focus, ictal onset, or a lesion on magnetic resonance imaging scanning) and one to the temporal lobe (interictal spikes or seizure onset). We discuss seizure characteristics, electroencephalographic (EEG), magnetic resonance imaging, positron emission tomographic, and single-photon emission computed tomographic findings, pathological findings, surgical approach, outcome from resective surgery, and implications for pathophysiology. Sixty-nine percent of our 16 patients with occipitotemporal syndrome had neuronal migration disorder, suggesting a developmental etiology of this entity. Initial signs or symptoms suggested occipital lobe seizure onset in 13 of 16 patients. On scalp EEG, interictal spikes were localized to the temporal lobe in 9 and to the occipital lobe in 1; seizure onset was poorly localized. Intracranial EEG localized seizure onset to the area of temporo-occipital junction in 77% of patients. Positron emission tomography and single-photon emission computed tomography showed occipital and temporal or widespread deficits, and neuropsychological performance was diffusely abnormal. Surgical results were best with occipital and temporal resections, but sometimes satisfactory after occipital resection even with temporal (ipsilateral) EEG findings. Temporal resection with hippocampectomy uniformly failed to control seizures. An often refractory, probably developmental epileptic syndrome with regional occipitotemporal distribution can be diagnosed by a specific constellation of findings, which has implications for treatment and pathophysiology.     

Depth Electrode Studies in Temporal Lobe Epilepsy: Relation to Quantitative Magnetic Resonance Imaging and Operative Outcome

Summary: We performed a retrospective study of 30 patients with presumed intractable temporal lobe epilepsy (TLE) who underwent chronic intracranial EEG monitoring (CIEM). Multicontact depth electrodes were stereotactically implanted through the medial occipital lobe into amygdala and hippocampus. All patients had previously undergone extracranial ictal EEG monitoring that proved inadequate to localize the epileptogenic zone. No morbidity as associated with CIEM in the 30 patients. Twenty-five patients were shown to have exclusively or predominantly unilateral temporal lobe seizures, and 5 patients had bitemporal seizures without unilateral predominance; 24 patients subsequently underwent an anterotemporal lobe cortical resection. Twenty-one patients have been followed a minimum of 1 year postoperatively. Nine patients (43%) had a class I outcome (seizure-free, auras only, or provoked seizures), 3 patients (14%) had a class I1 outcome (≥95% seizure reduction), 4 patients (19%) had a class III outcome (≥50% seizure reduction); and 5 patients (24%) had a class IV outcome (<50% seizure reduction or no change). A prolonged interhemispheric propagation time (p <0.01) and magnetic resonance imaging (MR1)-identified hippocampal atrophy (p <0.01) correlated with a favorable surgical outcome. Results of this study may prove useful in counseling patients who undergo CIEM before temporal lobe surgery.     

癫(癎)患者先兆症状的研究

目的 探讨癫(癎)患者先兆症状的发生比例、临床表现,为正确诊断治疗癫(癎)提供依据.方法 回顾性研究1028例癫(癎)患者的临床资料,分析癫(癎)患者的先兆发生率、临床表现、脑电图和神经影像学结果.比较伴或不伴先兆的部分性发作癫(癎)患者的发病年龄、性别、脑电图、神经影像学的差异以及腹部先兆在颞叶内外侧癫(癎)出现比例的差异.结果 部分性癫(癎)725例,484例(66.8 % )出现先兆;全面性发作者303例,无一例患者出现先兆.64例患者出现2种或2种以上的先兆表现;14例出现持续性先兆的癫(癎)患者.1028例患者中脑电图异常547例(53.2 % ),影像学异常217例(21.1 % ).484例有先兆症状的患者中286例脑电图异常(59.1 % ),126例(26.0 % )影像学异常.伴或不伴先兆的部分性发作癫(癎)患者的首次发病年龄差异无统计学意义,腹部先兆在颞叶内外侧癫(癎)出现的比例差异有统计学意义(x2=170.877,P<0.01).结论 癫(癎)患者先兆症状多样,分析先兆症状对于癫(癎)分型、病灶定位以及合理治疗有指导意义.