Event-related potential (P300) in epilepsy

The P300 component of auditory event-related potential was studied in 39 patients with temporal lobe epilepsy (TLE), 26 with idiopathic generalized epilepsy (IGE) and 28 controls. The age-corrected P300 latencies were significantly longer in TLE patients compared with those in IGE patients and controls. Neither the duration of epilepsy nor clinical manifestation was related to the P300 component in the same epileptic syndrome. The age-corrected P300 latencies recorded from Cz were significantly prolonged in TLE patients with bilateral temporal EEG foci compared with those with unilateral focus. The effects of anti-epileptic drugs on the P300 component were not significant. Our findings imply that prolonged P300 latency in TLE patients, especially in those with bilateral EEG foci is due to damage of the hippocampus, which is potentially an epileptogenic focus.     

Reading abilities and cognitive functions of children with epilepsy: influence of epileptic syndrome

Children with epilepsy are at risk of developing learning disorders. To explore the influence of the epileptic syndrome on reading abilities, we have compared the neuropsychological profile of 12 children with benign idiopathic epilepsy with rolandic spikes, 10 with temporal lobe epilepsy and 12 with idiopathic generalized epilepsy. Children underwent a selection of standardised tests designed to assess: oral language, reading, short-term memory, attention and behavioural adjustment. Analysis of variance was adjusted according to age of onset of the epileptic syndrome, duration of the syndrome, and performance IQ for each group. Children with temporal lobe epilepsy (TLE) had significantly lower scores for reading speed and comprehension, but epileptic variables (the age of onset of epilepsy, duration and activity of epilepsy) had influenced academic performances. In the TLE group there was a clear effect of the topography of the epileptic foci (left-side TLE vs. right-side TLE) on reading profile. Furthermore, the effect of epileptic syndromes was found in phonological, semantic and verbal working memory deficits in the TLE group. To a lesser extent children with idiopathic generalized epilepsy (IGE) also exhibit cognitive deficit. The results of the present study lend support to epilepsy-specific patterns of neuropsychological dysfunction in children that should be considered to improve remediation of academic underachievement in these populations.     

Seizure frequency affects event-related potentials (P300) in epilepsy.

To analyse the effect of epilepsy an P300 event-related potentials we studied 27 patients with idiopathic generalized epilepsy (IGE), 13 patients with temporal lobe epilepsy (TLE) and 60 normal controls. The prolongation of P300 latencies was highly cor related with increasing age in controls but not epileptic patients. The age-corrected P300 latency used in this study was actual P300 latency-predicted P300 latency (predicted P300 (msec)=306.20+0.79 age, P=0.001, R2=0.32). By using ANOVA analysis, the age-corrected latencies of P300 were significantly longer in TLE patients (19.72+/-47.82 msec, mean+/-SD) than in IGE patients (10.97+/-36.97 msec) and controls (0.23+/-20.28 msec). Likewise, significantly prolonged P300 latencies were seen in the epileptic patients with a seizure frequency more than 400 times (37.21+/-47.50 msec). The multivariate-adjusted odds ratio for those who had TLE was 10.97 (95% CI=3.99 - 30.14 ) in the prolonged latencies of P300 compared with that of IGE patients. The odds ratio of longer latencies of P300 was 7.43 (95% CI=2.75 - 20.08) among those who had a high seizure frequency (> or =400 times) compared with those who had a low seizure frequency. No interaction between TLE and high frequency of attacks was found. The age at onset of seizure and duration of illness was not associated with P300 latency prolongation. From the above results, we might infer that the seizure type of TLE and a high frequency of seizure are two major independent precipitate factors for abnormal latencies of P300 in the epileptic patients.     

Development of intracranial tumors in patients with long-standing preexisting epilepsy

We report 8 patients who had an intracranial tumor intercurrently with long-standing preexisting epilepsy. In 4 [3 idiopathic generalized epilepsies (IGE), 1 frontal lobe epilepsy (FLE)], the tumor was extracerebral or subcortical (2 craniopharyngiomas, 1 germinoma, 1 meningioma) and did not affect the course of epilepsy. In 4 [1 IGE, 2 FLE, 1 temporal lobe epilepsy (TLE)], the tumor was superficial and intracerebral (3 astrocytomas, 1 oligodendroglioma) and the first sign of tumor was a change in the intensity or symptoms of epilepsy. Diagnosis of the tumor was delayed in the second group. Clinical and biologic evidence suggest that epilepsy and antiepileptic drugs are not risk factors for brain tumors. However, clinicians should bear in mind that not all brain tumors cause epileptic seizures and that patients with various types of epilepsy can develop brain tumors. Aggravation or change in the symptomatology of epilepsy warrants thorough investigation to rule out the possibility of development of an intercurrent brain tumor.     

Psychopathology and personality characteristics of epileptic patients: epilepsy, psychopathology and personality

The psychiatric investigation of a sample of 101 epileptic patients (65 temporal lobe epileptics (TLE) and 36 non-TLE) through various methods of evaluation, showed that only a minority of TLE with DSM-III diagnoses of Organic Brain Syndromes had severe psychopathology and manifested some personality traits. Thus, these patients seem to be differentiated from the rest of epileptics, TLE and non-TLE, who had quite "benign" psychological problems, if at all. It is quite probable that this sub-group of TLE could be the main instigators and perpetrators of the "bad image" of epileptics. The findings are discussed in relation to the pertinent literature and some hypotheses are offered for their explanation.     

The generalized tonic-clonic seizure in partial versus generalized epilepsy: semiologic differences

PURPOSE: To study differences in the clinical manifestations of generalized tonic-clonic seizures (GTCS) of partial versus generalized onset. METHODS: We studied 10 GTCSs in nine patients with idiopathic generalized epilepsy (IGE) and 10 GTCSs in 10 patients with temporal lobe epilepsy (TLE). Videotaped seizures were reviewed for all clinical features, focusing on asymmetries during different phases of each seizure. RESULTS: In the IGE group, focal features were seen before generalized motor activity in seven seizures. The most common was adversive head turn (six seizures). One patient had opposite direction of head turning in two recorded seizures. The tonic phase was always symmetric. In the last generalized clonic phase, asymmetry or asynchrony of motor activity was seen transiently in three seizures. The TLE group showed focal features before generalization in all seizures. Adversive head turning occurred in nine patients and was always contralateral to the focus. Focal clonic activity occurred before generalization in three and was always contralateral to the focus. The generalized tonic phase was usually asymmetric, and in the last clonic phase, motor activity was asymmetric or asynchronous in eight seizures (p<0.05, IGE vs. TLE). CONCLUSIONS: Brief focal features or asymmetry at onset are common in the GTCSs of IGE. However, asymmetry or asynchrony during the last clonic phase are uncommon in IGE, in contrast to TLE.     

Social cognition dysfunctions in patients with epilepsy: Evidence from patients with temporal lobe and idiopathic generalized epilepsies

Background and aimDespite an extensive literature on cognitive impairments in focal and generalized epilepsy, only a few number of studies specifically explored social cognition disorders in epilepsy syndromes. The aim of our study was to investigate social cognition abilities in patients with temporal lobe epilepsy (TLE) and in patients with idiopathic generalized epilepsy (IGE).Materials and methodsThirty-nine patients (21 patients with TLE and 18 patients with IGE) and 21 matched healthy controls (HCs) were recruited. All subjects underwent a basic neuropsychological battery plus two experimental tasks evaluating emotion recognition from facial expression (Ekman-60-Faces test, Ek-60F) and mental state attribution (Story-based Empathy Task, SET). In particular, the latter is a newly developed task that assesses the ability to infer others' intentions (i.e., intention attribution — IA) and emotions (i.e., emotion attribution — EA) compared with a control condition of physical causality (i.e., causal inferences — CI).ResultsCompared with HCs, patients with TLE showed significantly lower performances on both social cognition tasks. In particular, all SET subconditions as well as the recognition of negative emotions were significantly impaired in patients with TLE vs. HCs. On the contrary, patients with IGE showed impairments on anger recognition only without any deficit at the SET task.DiscussionEmotion recognition deficits occur in patients with epilepsy, possibly because of a global disruption of a pathway involving frontal, temporal, and limbic regions. Impairments of mental state attribution specifically characterize the neuropsychological profile of patients with TLE in the context of the in-depth temporal dysfunction typical of such patients.ConclusionImpairments of socioemotional processing have to be considered as part of the neuropsychological assessment in both TLE and IGE in view of a correct management and for future therapeutic interventions.     

Entorhinal cortex MRI assessment in temporal,extratemporal, and idiopathic generalized epilepsy

PURPOSE: We previously showed a reduction in the volume of the entorhinal cortex (EC) ipsilateral to the seizure focus in patients with intractable temporal lobe epilepsy (TLE). The purpose of this study was to examine the specificity of EC atrophy in epilepsy. METHODS: We performed volumetric measurement of the EC on high-resolution magnetic resonance imaging (MRI) in patients with TLE (n = 70), extratemporal lobe epilepsy (ETE; n = 18), and idiopathic generalized epilepsy (IGE; n = 20). EC volumes of epilepsy patients were compared with those of 48 age- and sex-matched normal controls. Within the TLE group, 63 patients were selected prospectively with hippocampal atrophy ipsilateral to the seizure focus. The remaining seven patients were chosen retrospectively based on normal volumetric MRI of the hippocampus and amygdale, as well as normal histopathologic examination of the resected tissue. RESULTS: Compared with normal controls, EC volume was smaller ipsilateral but not contralateral to the seizure focus in patients with TLE (p < 0.001). No difference in the EC volumes ipsilateral and contralateral to the seizure focus was seen in patients with ETE and IGE compared with normal controls. The individual analysis showed that the EC was atrophic in 73% of TLE patients with hippocampal atrophy. Three of the seven TLE patients with normal volumetric MRI of the hippocampus and amygdala and normal histopathologic examination had EC atrophy ipsilateral to the seizure focus. In no patient with ETE or IGE was the EC found to be atrophic. CONCLUSIONS: EC atrophy ipsilateral to the seizure focus appears to be specific to mesial temporal lobe structural damage associated with TLE.     

A comparative study of obsessive–compulsive disorder and other psychiatric comorbidities in patients with temporal lobe epilepsy and idiopathic generalized epilepsy

Our aim was to assess the associations of temporal lobe epilepsy (TLE) and idiopathic generalized epilepsy (IGE) with comorbid psychiatric conditions, especially obsessive–compulsive disorder (OCD), in a comparative design. We evaluated 29 patients with TLE, 27 patients with IGE, and 30 healthy controls. The Structured Clinical Interview for DSM-IV (SCID), Yale–Brown Obsessive Compulsive Scale (Y-BOCS) Symptom Checklist, and Beck Depression Inventory (BDI) were administered. Among patients with TLE, 75.9%, and among patients with IGE, 48.1% had at least one Axis I psychiatric disorder. Clinically meaningful obsessive–compulsive symptoms (CM-OCS) were noted in 10 patients with TLE and in 3 patients with IGE, and this difference was statistically significant (P < 0.05). CM-OCS were present in 9 of 18 patients with left-sided TLE, but in only 1 of 11 patients with right-sided TLE. Higher comorbidity in TLE suggests that involvement of the temporal lobe may play a role in the development of specific psychopathological syndromes.     

A comparison of post-ictal headache between patients with occipital lobe epilepsy and temporal lobe epilepsy.

We investigated post-ictal headaches (PIH) using a questionnaire to ascertain their characteristics and compare them among different types of epilepsy. The subjects consisted of 34 patients with occipital lobe epilepsy (OLE) and 75 patients with temporal lobe epilepsy (TLE). PIH occurred in 62% of OLE and 23% of TLE (P < 0.05). The quality of pain in PIH was 'steady' in 71% of OLE and 29% of TLE (P < 0.05) as opposed to 'pounding'. Other factors, such as frequency, severity, duration, and accompanying symptoms showed no significant differences. We found very few patients with migraine-like headaches. Analyses of clinical factors, such as age at onset, duration of epilepsy, seizure frequency, family history of headache, and interictal headache did not reveal any relationship to PIH, although generalized tonic-clonic seizures are associated with PIH in TLE (P < 0.05). These results suggest that the nature of PIH may be different between OLE and TLE, and that the region of epileptic focus or spreading area of epileptic discharge may have a close relation to the induction of PIH. An association with migraine, which has been reported previously, was unclear in our study.     

Coexistence of temporal lobe and idiopathic generalized epilepsies.

OBJECTIVE: To assess the interrelation of idiopathic generalized epilepsy (IGE) and temporal lobe epilepsy (TLE) when they coexist in the same patient. METHODS: The authors reviewed the electroclinical features of 350 consecutive patients who had temporal resection between 1975 and 1997 at the Maudsley and King's College Hospitals, London. RESULTS: Two patients had the unusual combination of TLE and IGE (0.57%). In the first, the clinical onset of juvenile myoclonic epilepsy followed the surgical resolution of his partial seizures but had been heralded for at least 5 years by subclinical spontaneous and photically induced generalized spike-wave discharges. In the second, TLE and juvenile absence epilepsy had a long parallel course before surgery. After surgery he had no further partial seizures. CONCLUSION: These cases suggest that when an idiopathic absence or myoclonic syndrome manifests in a patient with symptomatic TLE, the phenotype may not be a merged syndrome. Rather, the two conditions can retain their inherent electroclinical profile, responsiveness to treatment, and prognosis.     

Obsessionality, obsessive-compulsive disorder, and temporal lobe epilepsy

We evaluated the prevalence of obsessive-compulsive disorder (OCD) in patients with temporal lobe epilepsy (TLE) and we investigated the hypothesis that obsessionality may represent a trait in TLE. Eighty-two consecutive patients with epilepsy, 62 with TLE and 20 with idiopathic generalized epilepsy (IGE), and 82 matched healthy controls were evaluated using the SCID-IP, Y-BOCS, MMPI-2 (specifically the Psychasthenia and Obsessiveness scales), BDI, and STAI Y1 and Y2. Nine of the TLE patients, none of the IGE patients, and one of the controls had a diagnosis of OCD. Psychasthenia and Obsessiveness scores were significantly higher in the TLE than in the IGE and control groups. Patients with TLE and OCD differed significantly with respect to history of depression when compared with patients with TLE without OCD, whereas there were no differences in age at onset and duration of epilepsy, seizure pattern and frequency, MRI features, laterality of the EEG focus, antiepileptic drug therapy and combinations, and BDI scores.     

Helicobacter pylori infection in patients with epilepsy

BackgroundThe possible role of Helicobacter pylori (HP) infection in extra-intestinal diseases has been suggested. The main purpose of this study was to determine the frequency of infection with HP in two groups of patients with epilepsy: patients with idiopathic generalized epilepsy (IGE) and patients with temporal lobe epilepsy (TLE), compared to healthy controls.MethodsIn this cross-sectional study a random sample of adult patients above 18 years of age with a diagnosis of IGE or TLE were recruited at the outpatient epilepsy clinic at Shiraz University of Medical Sciences, from January 2009 through June 2011. A group of healthy individuals were included as control group. For all patients and controls a urea breath test (UBT) was requested.ResultsThirty-four patients with IGE, 28 patients with TLE and 33 individuals as control were recruited. Positive UBT was observed in 21 individuals (61.8%) with IGE, 50% (14 patients) of patients with TLE and 72.7% (24 individuals) in control group. The difference between patients with IGE and control group was not significant (P = 0.3). The difference between patients with TLE and control group was not significant either (P = 0.068).ConclusionThe rate of HP infection was not higher in patients with epilepsy compared to healthy individuals. At the moment, there is not enough epidemiological data to support the role of HP infection in patients with either IGE or TLE.     

Clinical factors associated with post-ictal headache in patients with epilepsy

OBJECTIVES: To determine the incidence of post-ictal headaches (PIH) and clinical risk factors associated with the occurrence of PIH in patients with localization-related epilepsy. MATERIALS AND METHODS: The subjects were 77 patients with temporal lobe epilepsy (TLE), 34 patients with occipital lobe epilepsy (OLE), and 50 patients with frontal lobe epilepsy (FLE). The subjects were directly asked whether headaches occurred just after seizures. Medical charts were reviewed to ascertain the clinical characteristics of epilepsy in these patients. RESULTS: The incidence of PIH was 23% for TLE, 62% for OLE, and 42%, for FLE. The risk of PIH was significantly higher for OLE than for TLE or FLE, and for patients with generalized tonic-clonic seizures. Younger age at onset of epilepsy was also a risk factor for PIH. CONCLUSION: The occurrence of PIH may be related to the region of epileptic focus and the region of spread of epileptic discharges.     

Investigation of social and emotion information processing in temporal lobe epilepsy with ictal fear

This study examined whether patients with temporal lobe epilepsy (TLE) and ictal fear (IF) show emotion recognition deficits similar to those associated with amygdala damage. Three groups of patients (13 with TLE and IF, 14 with TLE and nonfear auras (non-IF), and 10 with idiopathic generalized epilepsy (IGE)) completed tests of visual and face processing, face emotion recognition and social judgment, together with measures of psychological adjustment (Hospital Anxiety and Depression Scale; SCL-90-R) and Quality of Life (QOLIE-31). All three epilepsy groups had fear recognition deficits, with relatively greater impairments in the IF group. Fear recognition deficits were associated with impaired social judgment of trustworthiness, duration of epilepsy, and a measure of quality of life. Social cognition impairments previously associated with amygdala dysfunction are also a feature of the neuropsychology of TLE, and extend the hypothesis in that they may additionally play a role in IGE.     

Tonic status epilepticus in patients with idiopathic generalized epilepsy.

RATIONALE: Tonic status epilepticus (TSE) in patients with idiopathic generalized epilepsy (IGE) is not well recognized. The objective of this study is to report episodes of TSE in patients with IGE. METHODS: We retrospectively reviewed the clinical and EEG evaluation of three IGE patients who presented TSE. RESULTS: The three patients had mainly clinical features of IGE, but had developed, in addition, focal discharges, diffuse EEG abnormalities and some focal or diffuse neuropsychological dysfunction. The tonic attacks eventually responded to treatment, but were not completely controlled in any of the patients. DISCUSSION: The continuum between IGE and secondary generalized epilepsy is demonstrated in these patients. Most of their clinical and EEG features are however, in keeping with an idiopathic generalized epileptic process with additional focal and diffuse components. Recognition of the significance of TSE in such patients has important therapeutic and prognostic implications. [Published with video sequences].     

Autonomic responsiveness to affective visual stimulation in temporal lobe epilepsy

Patients with temporal lobe epilepsy (TLE) have been posited by some to manifest a syndrome of interictal personality and behavioral change. Furthermore, this syndrome has been attributed to an underlying mechanism--enhanced affective responsiveness. The purpose of this investigation was to determine whether patients with TLE manifest increased emotional responsiveness relative to appropriate controls. Patients with TLE (n = 23) were compared with non-TLE (n = 7) and healthy controls (n = 16) as to their autonomic nervous system responsiveness to an emotionally stressing film. No differences were found among the groups. These results are related to the larger literature concerning epilepsy and psychopathology.     

Vagus nerve stimulation for refractory idiopathic generalised epilepsy.

We reviewed our experience with vagus nerve stimulation (VNS) in 165 patients with medically refractory epilepsy (138 partial epilepsy (PE), 13 symptomatic generalised epilepsy (SGE), 14 idiopathic generalised epilepsy (IGE)). Average duration of VNS therapy was 21.6 months. A 50% or greater reduction in seizure frequency was achieved in 47.1% of the PE group, 46.1% of the SGE group, and 57.1% of the IGE group. A 50% or greater reduction in seizure frequency and reduced antiepileptic drug (AED) regimen were achieved in: PE (9.4%), SGE (7.7%), and IGE (35.7%). These preliminary results suggest that VNS is an effective therapy for some patients with medically refractory IGE.     

Accelerated long-term forgetting in temporal lobe but not idiopathic generalised epilepsy

Temporal lobe epilepsy (TLE) has been associated with the phenomenon of accelerated long-term forgetting (ALF), in which memories are retained normally over short delays but are then lost at an accelerated rate over days or weeks. The causes of ALF, and whether it represents a consolidation deficit distinct from the one associated with forgetting over short delays, remain unclear. In addition, methodological issues have made results of some previous studies difficult to interpret. This study used improved methodology to investigate the role of seizure activity in ALF. Forgetting was assessed in participants with TLE (who have involvement of temporal lobe structures) and idiopathic generalised epilepsy (IGE; in which seizures occur in the absence of identified structural pathology in the temporal lobes). Learning of novel stimuli was matched between patients with TLE, patients with IGE and healthy controls matched for age and IQ. Results indicated that the TLE group showed accelerated forgetting between 30-min and three-weeks, but not between 40-s and 30-min. In contrast, rates of forgetting did not differ between patients with IGE and controls. We conclude that (1) ALF can be demonstrated in TLE in the absence of methodological confounds; (2) ALF is unlikely to be related to the experience of epilepsy that does not involve the temporal lobes; (3) neither seizures during the three-week delay nor polytherapy was associated with ALF.     

Memory for public events in patients with unilateral temporal lobe epilepsy

Memory for public events (PEs) was assessed as a marker of remote declarative memory in 36 patients with temporal lobe epilepsy (TLE) and compared with that of 19 patients with extra-TLE (ETLE), 17 patients with idiopathic generalized epilepsy (IGE), and 23 healthy volunteers. Verbal IQ, inventory-based evidence of depression, handedness, onset of illness, disease duration, and medication were obtained. Memory for PEs was reduced in all patient groups (TLE, P < 0.0001; ETLE, P = 0.009; IGE, P = 0.008). The TLE group showed reduced memory for PEs compared with the other patients with epilepsy (P = 0.001). A time gradient was observed, with worse memory for PEs of the 1990s and for PEs that occurred after onset of illness. Our data support the key role of the temporal lobe in remote declarative memory. With patients with TLE remembering fewer PEs from the period after onset of epilepsy, the deficits can be partly attributed to unsuccessful consolidation rather than retrieval difficulties alone.