A clinical and electroencephalographic study of juvenile myoclonic epilepsy: its pathophysiological considerations based on the findings obtained from neuropsychological EEG activation

Juvenile myoclonic epilepsy (JME) is one of the idiopathic generalized epilepsies with age-related onset. Myoclonic seizures of JME often occur on awakening. On the other hand, patients with reflex epilepsy, whose seizures are particularly induced by activating higher cognitive functions, are thought to belong to the same category. As to the seizure precipitating factors of these patients with JME, however, few studies have ever been made. In this study, clinical and electroencephalographic findings of 25 patients with JME, on whom "neuropsychological EEG activation" (NPA) was performed, were carefully analyzed. After a routine EEG examination, NPA was carried out; this is a special method for EEG activation that requires the patients to speak, read, write, calculate and perform constructive acts (drawing figures and doing a block design test); in addition to EEG recording, simultaneous video-EEG monitoring was also made during these tasks. In the patients with JME, the sex ratio was about equal (11 males and 14 females). Eight patients (32%) had a family history of epilepsy but none of the patients had a positive past history responsible for epilepsy. The age at the onset of myoclonic seizures ranged between 10 and 20 years (mean: 15.3 years). A total of 18 patients (72%) had another type of seizures; 3 had absence seizures, 9 had generalized tonic-clonic seizures and 6 had both absence and generalized tonic-clonic seizures. Myoclonic seizures often occurred in the morning on awakening in 17 (68%) of 25 patients. As for EEG findings (all but one patient were receiving antiepileptic drugs when EEG was examined), paroxysmal discharges in a resting state were found in 12 patients (48%); most of them were either very brief generalized spike and wave complexes or bursts of generalized 3-5 Hz spike and wave complexes lasting for 1-3 seconds; generalized multiple spikes were observed only in 5 patients. These clinical and EEG findings were in accordance with those reported previously. Careful investigation of the histories obtained from the patients disclosed the following: Myoclonic seizures were induced (1) by mental activity associated with the use of hands in 20 patients (80%), (2) in a situation with psychic tension in 12 (48%), and (3) by decision making in 3 (12%). Interestingly, these findings could be confirmed by NPA with simultaneous video-EEG monitoring.(ABSTRACT TRUNCATED AT 400 WORDS)     

The Role of Cognitive–Motor Function in Precipitation and Inhibition of Epileptic Seizures

Summary:  Purpose: To examine the effects of cognitive–motor function on EEG discharges and the neuropsychological mechanisms of seizure induction in patients sensitive to cognitive–motor tasks.
Methods: Four hundred eighty patients with epilepsies were subjected to cognitive tasking, termed "neuropsychological EEG activation (NPA)." It consisted of reading, speaking, writing, written calculation, mental calculation, and spatial construction. Furthermore, patients showing a provocative NPA effect were subjected to a detailed NPA protocol to identify the possible precipitating factors, which consisted of simple hand movements, action programming requiring hand movement, and thinking activity not requiring hand movement.
Results: NPA had an inhibitory effect on EEG discharges in 133 (63.9%) of 208 patients with discharges in the awake EEG. Conversely, NAP had a provocative effect in 38 (7.9%) of 480 patients. In 32 of the 38 patients, the precipitating factor was action programming. Among them, five showed a precipitating factor restricted to linguistic activity, and the remaining 27 were affected by various action-programming factors including both linguistic and praxic activities. In four of 38 patients, the precipitating factor was thinking, predominantly linguistic tasks in one patient and spatial tasks in three patients. No patient had a precipitating factor identified as motor activity.
Conclusions: These results suggest that cognitive–motor function has an inhibitory effect on EEG discharges in the majority of epilepsy patients and a provocative effect in some patients, and that seizures of the patients showing a provocative NPA effect are precipitated by action programming or thinking activity.     

Usefulness of a morning routine EEG recording in patients with juvenile myoclonic epilepsy

OBJECTIVE: To evaluate if a standard awake EEG recording in the morning is superior to afternoon awake EEG session in detecting generalized epileptiform discharges (GEDs) in patients with juvenile myoclonic epilepsy (JME). METHODS: The study group included 29 consecutive patients (23 women; mean age 22.3+/-6.3 years; age at onset of JME 15.4+/-3.4 years) with JME. Out of 29 patients 5 were untreated, 9 patients were treated with valproate, 8 with lamotrigine, 6 with levetiracetam and 1 patient with valproate plus phenobarbital. Two routine consecutive interictal EEG recordings were performed at 9a.m. and at 3p.m., respectively, while the subject was awake, on the same day after a a regular nocturnal sleep at own home. RESULTS: The morning EEG recording showed GEDs (i.e., generalized polispike and waves, photoparoxysmal response, or both). in 20/29 patients. In 15 of these 20 patients, the afternoon recording was normal and this difference was statistically significant (p < or = 0.001). Moreover, there was a striking reduction of GEDs in three of the remaining five patients. Nine/29 patients had both morning and afternoon EEG recording normal. CONCLUSIONS: The results of this study have illustrated a significant greater rate of detection of generalized epileptiform abnormalities by performing standard awake EEG in the morning in comparison with an afternoon session.     

Chronodependency and provocative factors in juvenile myoclonic epilepsy

In juvenile myoclonic epilepsy (JME), occurrence of seizures and epileptiform EEG discharges is influenced by internal and external factors. The most important internal factor is the chronodependency: the occurrence of myoclonic jerks in the early morning is one of the hallmarks of JME. Approximately two-thirds of the patients with JME report that seizures are provoked by a variety of general factors like stress, fatigue, fever, and sleep and more specific precipitants like flashing sunlight, music, reading, thinking, and excess alcohol. The prevalence rate of photosensitivity (photoparoxysmal EEG response) in patients with JME ranges from 8 to 90%; it is seen more often in females and adolescents and depends on drug use. Since both JME and photosensitivity are connected with generalized types of epilepsy and myoclonus, the two traits are comorbid for that reason. Epileptiform EEG discharges can be provoked by other activation methods: sleep, hyperventilation, and specific cognitive tasks. Attention seems to have a non-specific, inhibitory effect of the epileptiform discharges. Hyperventilation can induce absence seizures in patients with JME, while cognitive tasks are efficient in precipitating myoclonic seizures.This article is part of a supplemental special issue entitled Juvenile Myoclonic Epilepsy: What is it Really?     

Long-term cognitive and behavioural follow-up in three patients with eye closure-triggered paroxysmal activity.

PURPOSE: To study clinical, EEG, neuropsychological and behavioural evolution of three patients presenting with epileptic activity triggered by eye closure (EC) over a mean 10-year follow-up period. METHODS: All patients were studied at the time of the first observation (T0) and after a long follow-up period (T1). At both T0 and T1, each patient underwent: 1) traditional and specific activation techniques during prolonged video-EEG monitoring to detect possible inducing factors; 2) neuropsychological evaluations during video-EEG monitoring either with eyes closed or eyes open to detect any transient cognitive impairment (TCI); 3) detailed neuropsychological assessment without simultaneous EEG recording, to detect any stable cognitive impairment (SCI). RESULTS: EEG recordings showed transient, generalized paroxysms in one case and a continuous epileptic activity triggered by eye closure in the other two cases, at both T0 and T1. In all patients, no particular epileptiform discharge-induced factors were identified except for eye blinking (spontaneous, voluntary or induced by corneal reflex). The results of neuropsychological assessment while eyes were closed as compared to performances with eyes open, showed no significant differences at T0 or at T1 in two cases, thus possibly indicating the absence of TCI. Wechsler Intelligence Scales showed a decrease in performance at T1 in the two patients with eye closure-induced, continuous epileptiform activity. Detailed neuropsychological assessment without EEG recordings demonstrated an impairment of facial recognition ability in all three patients at T1. CONCLUSIONS: The lack of any differences between the results of neuropsychological tests performed with eyes open and eyes closed in two patients might suggest that not all eye-closure-triggered paroxysms are associated with TCI. On the other hand, our data highlight that EC-triggered, EEG epileptic discharges can produce long-lasting neuropsychological and behavioural effects, and also indicate that EEG discharges recurring over time might exert a disruptive effect on cognitive functions. Our three patients showed extreme variability across the neuropsychological tasks except for a facial recognition deficit that was evident in all cases, thus suggesting a possible dysfunction of temporo-occipital brain structures and/or of the fusiform face area as recently demonstrated by combined fMRI/EEG studies in patients with fixation-off sensitivity.     

Focal semiologic and electroencephalographic features in patients with juvenile myoclonic epilepsy

PURPOSE: A few reports have described focal electroencephalographic or clinical features or both of juvenile myoclonic epilepsy (JME), but without video-EEG documentation. We examined focal clinical and EEG features in patients with JME who underwent video-EEG monitoring. METHODS: Twenty-six patients (nine males and 17 females) who had seizures recorded during video-EEG monitoring were included. Age at seizure onset was 0 to 22 years (mean, 12.3 years), and age at monitoring was 12 to 44 years (mean, 26.5 years). In one patient with left parietooccipital epilepsy, primary generalized tonic-clonic seizures developed after resection of the parietal tumor. Two patients had both temporal lobe epilepsy and JME. Videotaped seizures in each patient were analyzed. Interictal and ictal EEG also were analyzed for any focal features. RESULTS: Focal semiologic features were observed in 12 (46%) of 26 patients. Six patients had focal myoclonic seizures, and two had Figure 4 sign: one with version to the left, and another had left version followed by Figure 4 sign, and left arm clonic seizure. Their ictal EEGs were generalized at onset but with a lateralized evolution over the right hemisphere. The patient who had both JME and left parietooccipital epilepsy, right arm clonic seizure, and Figure 4 sign was seen during a generalized EEG seizure. Interictally, one patient had temporal sharp waves, and another had run of spikes in the right frontal region. CONCLUSIONS: Fourteen (54%) of 26 patients with JME exhibited focal semiologic or electroencephalographic features or both. Video-EEG was essential in reaching a correct diagnosis and choosing an appropriate antiepileptic drug regimen.     

Modulation of epileptiform EEG discharges in juvenile myoclonic epilepsy: an investigation of reflex epileptic traits

Purpose: Previous studies have suggested that cognitive tasks modulate (provoke or inhibit) the epileptiform electroencephalography (EEG) discharges (EDs) in patients with juvenile myoclonic epilepsy (JME). Their inhibitory effect was found to be especially frequent (64–90%). These studies arbitrarily defined modulation as a >100% increase or >50% decrease of the EDs compared with baseline, which may not sufficiently distinguish from spontaneous fluctuations. The aim of our study was to assess the modulation of EDs and the precipitation of myoclonic seizures by cognitive tasks and by conventional provocation methods, taking into account also the spontaneous fluctuation of EDs. Method: Sixty patients with JME underwent video‐EEG recordings including 50‐min baseline, sleep, hyperventilation, intermittent photic stimulation (IPS), and cognitive tasks. To account for spontaneous fluctuations of the EDs we divided the baseline period into 5‐min epochs and calculated the 95% confidence interval for the baseline EDs in each patient. Modulation was assumed when the number of EDs during any 5‐min test period was outside the 95% confidence interval. Key Findings: Using the arbitrary method, our results were similar to previous publications: Cognitive tasks seemed to inhibit the EDs in 94% of the patients, and to provoke them in 22%. However, when the spontaneous fluctuations were accounted for, inhibition was found in only 29% of the patients and provocation in 18%. A nonspecific effect of any cognitive task seemed to account for the observed significant inhibition in two‐thirds of the cases, but was observed in only one of the patients with significant provocation. Photoparoxysmal response was observed in 23% of the patients. When accounting for the spontaneous occurrence of EDs, IPS had provocative effect in 10% of the patients. Hyperventilation and sleep had provocative effect on EDs to an extent similar to the cognitive tasks (hyperventilation: 22%; sleep: 18%). The conventional provocation methods tended to be more efficient in patients who were not seizure free. Myoclonia were recorded most often during the cognitive tasks (10 patients). Significance: Spontaneous fluctuations of EDs account for most of the previously described inhibitory effect of the cognitive tasks. The provocative effect of the cognitive tasks is task‐specific, whereas the inhibitory effect seems to be related to cognitive activation in general.     

Clinical expression and EEG features of patients with juvenile myoclonic epilepsy (JME) from North India.

We aimed to characterize the clinical profile, EEG features and response to treatment of juvenile myoclonic epilepsy (JME) patients. We studied 103 JME probands with a standard protocol recording age of onset, type, frequency of seizures, EEG data, detailed family history and response to treatment in a superspeciality university hospital in New Delhi. The mean age of onset of disease was 14.01 +/- 3.14 years with a male to female ratio of 1.19 : 1. The myoclonic jerks were present in all the probands, generalized tonic-clonic seizures (GTCS) were present in 75.72% and 11.65% probands had absence seizures. The incidence of febrile convulsion (FC) was higher (9.7%) in our JME probands reflecting some ethnic variation or ascertainment bias. There was a considerable delay (of approximately 5.26 +/- 4.61 years) in the diagnosis of JME in our probands because most of the patients were referred from private physicians who were possibly not familiar with this epileptic syndrome in this part of the world or thought it was a milder variety of GTCS. The family history was positive in 25.24% JME probands among first- and second-degree relatives. An interictal EEG was found to be abnormal in 81 (78.64%) patients with the predominant abnormality being generalized polyspike and wave (PSW) discharges (39.80% probands). The majority of patients (80.58%) showed a good response to treatment with valproate alone. There was a subset of patients (11.65%) who required the addition of other antiepileptic drugs (AEDs) for control of GTCS: 7.76% of JME patients were diagnosed as cases of GTCS by private practitioners before they were registered in our study and their seizures were well controlled on other AEDs (without valproate) prescribed by the referring physicians (carbamazepine-4, phenytoin-2, clobazam-2). It is concluded that the clinical features and EEG data of JME probands were comparable to reports from other parts of the world except for the fact that the incidence of FC was higher in our JME patients. There was a delay in the diagnosis of JME due to unfamiliarity with the epileptic syndrome among private practitioners in this part of the world. There was a subset of JME patients who had complete seizure control on other AEDs besides valproate.     

Characteristics of valproic acid resistant juvenile myoclonic epilepsy.

Juvenile myoclonic epilepsy (JME) is often exquisitely responsive to treatment with valproic acid (VPA). However, a subset of patients does not respond to this medication and often has intractable seizures. We wanted to identify differences between these two subsets of JME patients. Charts of all JME patients followed at the Duke Epilepsy Center were reviewed. Clinical parameters, electroencephalogram (EEG) findings and magnetic resonance imaging (MRI) data were reviewed. These features were compared between patients with VPA sensitive and VPA resistant JME. Thirty-three patients with JME were identified: 23 (70%) were VPA sensitive (13 females, 10 males; mean age of onset 15.9 years) and 10 (30%) were VPA resistant (5 females, 5 males; mean age of onset 14.1 years). The VPA resistant group had a higher frequency of EEG asymmetries (40% vs. 10%); atypical seizure characteristics including auras and post-ictal confusion (30% vs. 4%); and intellectual deficiency (20% vs. 0%). Clinical characteristics combined with EEG data may help in predicting which JME patients will respond favorably to VPA. This study also raises the issue whether VPA resistant JME is in fact a localization-related epilepsy.     

Juvenile myoclonic epilepsy: non-classic electroencephalographical presentation in adult patients.

Although diagnosis of juvenile myoclonic epilepsy (JME), a common form of idiopathic generalized epilepsy, is based on clinical and electroencephalogram (EEG) criteria, at times clinical symptoms may be misleading, like the occurrence of asymmetric myoclonic jerks. Thus EEG assumes an important role in these cases, it can fail to show the classical polyspike and slow wave (PSW) discharges of JME, specially in a routine evaluation in older patients. We analyzed retrospectively EEG results of 35 patients with JME [Commission on Classification and Terminology of the International League Against Epilepsy (ILAE) Epilepsia 1989; 30: 389] aged 12-44 years. (mean 22.7 years) at first medical evaluation. EEG findings of 35 patients (19 females, 16 males) with JME consisted of normal tracings in 22.9 and 54.3% had at least one normal exam. EEG abnormalities present in 27 patients (77.1%) consisted of isolated generalized slowing in two and generalized discharges in 25: irregular spike and wave complexes (SWC) in 76%; PSW in 48%; SWC faster than 3 Hz in 20%; spikes, sharp waves, and irregular slow waves in 24%; asymmetric generalized epileptiform discharges in 40%; and associated focal paroxysms in 12%. Thus JME is classically associated to PSW on EEG, the most frequent abnormality was irregular SWC. Generalized paroxysms could occur in an asymmetric fashion and rarely associated to focal activity.     

Provocative and inhibitory effects of a video-EEG neuropsychologic protocol in juvenile myoclonic epilepsy

Purpose:   Studies suggest that higher cognitive functions could precipitate seizures in juvenile myoclonic epilepsy (JME). The present study aimed to analyze the effects of higher mental activity on epileptiform discharges and seizures in patients with JME and compare them to those of habitual methods of activation.
Methods:   Seventy-six patients with JME (41 female) underwent a video-EEG (electroencephalography) neuropsychologic protocol (VNPP) and habitual methods of activation for 4–6 h.
Results:   Twenty-nine of the 76 (38.2%) presented provocative effect, and inhibition was seen in 28 of 31 (90.3%). A mixed effect was observed in 11 (35.5%), and 30 patients (39.5%) suffered no effect of VNPP. Action-programming tasks were more effective than thinking in provoking epileptiform discharges (23.7% and 11.0% of patients, respectively, p = 0.03). Inhibitory effect was observed equally in the various categories of tasks, except in mental calculation, which had a higher inhibitory rate. Habitual methods of activation were more effective than VNPP in provoking discharges. Anxiety disorders were diagnosed in 24 of 58 patients (41.4%); anxious patients had greater discharge indexes and no significant inhibitory effect on VNPP.
Discussion:   Praxis exerted the most remarkable provocative effect, in accordance with the motor circuitry hyperexcitability hypothesis in JME. Inhibitory effect, which had no such task specificity, might be mediated by a widespread cortical–thalamic pathway, possibly involving the parietal cortex. The frequent inhibitory effect found under cortical activation conditions, influenced by the presence of anxiety, supports nonpharmacologic therapeutic interventions in JME.     

Juvenile myoclonic epilepsy: a clinical and sleep EEG study.

Juvenile myoclonic epilepsy (JME) is characterized by myoclonic jerks on awakening, generalized tonic--clonic seizures (GTCS) and is associated with absence seizures in more than one third of cases. Fifteen patients with juvenile myoclonic epilepsy were studied with regard to their clinical profile, EEG data and sleep EEG findings. There was a delay in the diagnosis of JME (mean of 3.5 years) due to various reasons. Sleep deprivation was the most common precipitating factor for triggering seizures, followed by fatigue. Routine EEGs were abnormal in 73.33% of cases only and had misleading findings in 6.66%. Sleep EEGs were abnormal in 100% of cases with generalized spikes, polyspikes and slow wave discharges. Discharge rates on sleep EEGs typically increased significantly during the transition phase (i.e. the asleep to awakening stage) and we consider this to be a specific finding in appropriate clinical setting. Sleep EEGs are a more sensitive and specific tool for the diagnosis of JME while routine awake EEGs may miss or mislead.     

Evaluation of cognition, structural, and functional MRI in juvenile myoclonic epilepsy

Purpose:  Previous studies using advanced imaging techniques have suggested subtle structural and functional changes in patients with juvenile myoclonic epilepsy (JME), mainly associated with the frontal lobes. In addition, it has been reported that these patients show neuropsychological deficits, often summarized as frontal lobe dysfunction. The aim of this study was a comprehensive analysis of neuropsychological parameters, and functional and structural magnetic resonance imaging (MRI) in an independent cohort of patients with JME.
Methods:  We studied 19 JME patients and 20 age-, sex-, and education-matched controls using a battery of standardized neuropsychological tests, optimized voxel-based morphometry (VBM), and two domain-specific working-memory paradigms combined with functional MRI (fMRI).
Results:  Our investigations did not reveal statistically significant differences between the groups of JME patients and normal controls in either the VBM or the fMRI study of working memory. The neuropsychological examination showed a slightly worse performance for the JME patients across most tests used, reaching statistical significance for semantic and verbal fluency.
Conclusions:  In our cohort of JME patients, we could not reproduce the findings of frontal gray matter changes from previous studies, and we could not detect an fMRI correlate of previously reported differences in working memory in JME. The neuropsychological deficits may be attributed partially to antiepileptic medication. We conclude that structural and functional frontal lobe deficits in JME patients have to be interpreted with care. One reason for a variation between different cohorts may be the genetic heterogeneity of the disease.     

Cognitive tasks as provocation methods in routine EEG: a multicentre field study

Objective: This study aimed to analyse the effect of neuropsychological activation methods on interictal epileptiform discharges, compared to standard activation methods, for both focal and generalized epilepsies. Methods: This was a multicentre, prospective study including 429 consecutive EEG recordings of individuals with confirmed or suspected diagnosis of epilepsy. Neuropsychological activation included reading aloud in foreign and native language, praxis and a letter cancelation task (each with a duration of three minutes). After counting interictal discharges in three‐minute time windows, activation and inhibition were assessed for each procedure, accounting for spontaneous fluctuations (95% CI) and compared to the baseline condition with eyes closed. Differences between generalized and focal epilepsies were explored. Results: Interictal epileptiform discharges were present in 59.4% of the recordings. Activation was seen during hyperventilation in 31%, in at least one neuropsychological activation method in 15.4%), during intermittent photic simulation in 13.1% and in the resting condition with eyes open in 9.9%. The most frequent single cognitive task eliciting activation was praxis (10.3%). Lasting activation responses were found in 18–25%. Significant inhibition was found in 88/98 patients with baseline interictal epileptiform discharges, and was not task‐specific. Significance: Adding a brief neuropsychological activation protocol to the standard EEG slightly increased its sensitivity in patients with either focal or generalized epilepsy. However, in unselected epilepsy patients, this effect seems only exceptionally to result in ultimate diagnostic gain, compared to standard procedures. From a diagnostic perspective, cognitive tasks should be reserved for patients with a suspicion of cognitive reflex epilepsy/seizures and probably require longer exposure times. Further research is needed to explore potential therapeutic applications of the observed inhibition of interictal epileptiform discharges by cognitive tasks in some patients.     

Pitfalls in diagnosis of epilepsy of Janz and its implications

84 patients of juvenile myoclonic epilepsy (JME) of Janz were studied. Diagnosis was confirmed using clinical and electro-encephalographic (EEG) criterias. 58 (78%) patients of JME were referred as 'refractory or uncontrolled seizures'. Ignoring myoclonic episodes and non-use of activation procedures in EEG were important reasons for diagnostic delay. Sodium valproate (VPA) or clonazepam are the drugs of choice while phenobarbitone (PB), carbamazepine (CZ), and phenytoin (PHT) are ineffective. Clinical spectrum of JME is slightly different in India. Family history of epilepsy or JME is not forthcoming and there is gross delay in the diagnosis. Other differences include age of presentation and mild cognitive impairment. All juvenile patients of generalized epilepsy, not responding to more commonly used CZ, PB and PHT should be strongly suspected for JME by carefully searching for myoclonus.     

The Seizure Prognosis of Juvenile Myoclonic Epilepsy

Abstract: Thirty-two patients with juvenile myoclonic epilepsy (JME) were studied to evaluate the seizure prognosis. The response to antiepileptic drugs ww excellent in 68%, but the patients, who had much more focal discharges on EEG and were sensitive to neuropsychological EEG activations at the beginning of treatment, had an unfavorable outcome. A combination of absence seizure alone resulted in the excellent prognosis for both absence and myoclonic seizures, and a combination of generalized tonic-clonic seizure on awakening related to rare myoclonic seizures. These findings suggest that the outcome of JME would be predicted by the EEG abnormality and the combination of the other types of seizures, which are probably determined by the pathophysiology at the beginning of treatment.     

Clinical and EEG Asymmetries in Juvenile Myoclonic Epilepsy

Summary: We reviewed records of 85 patients with juvenile myoclonic epilepsy (JME) for significant asymmetries in clinical seizures or the EEG. We noted asymmetries in 26 of 85 patients (30.6%). Only 2 patients had both clinical and EEG asymmetries; 12 had clinical asymmetries and 12 had EEG asymmetries exclusively. Analysis of patients with and without asymmetries showed no statistically significant differences in comparisons of sex, age at seizure onset, family history of epilepsy, seizure type, or response to treatment. The delay in diagnosis was greater in JME patients with asymmetries (9.5 years) than in JME patients with no asymmetries (7.5 years), but this difference was not statistically significant. Fourteen of the 26 patients with asymmetries (53.8%) were initially misdiagnosed as having partial seizures. Asymmetries in JME patients are not only common, but are also a frequent cause of misdiagnosis.     

A study of idiopathic generalised epilepsy in an Irish population.

Idiopathic generalised epilepsy (IGE) is subdivided into syndromes based on clinical and EEG features. PURPOSE: The aim of this study was to characterise all cases of IGE with supportive EEG abnormalities in terms of gender differences, seizure types reported, IGE syndromes, family history of epilepsy and EEG findings. We also calculated the limited duration prevalence of IGE in our cohort. METHODS: Data on abnormal EEGs were collected retrospectively from two EEG databases at two tertiary referral centres for neurology. Clinical information was obtained from EEG request forms, standardised EEG questionnaires and medical notes of patients. RESULTS: two hundred twenty-three patients met our inclusion criteria, 89 (39.9%) male and 134 (60.1%) females. Tonic clonic seizures were the most common seizure type reported, 162 (72.65%) having a generalised tonic clonic seizure (GTCS) at some time. IGE with GTCS only (EGTCSA) was the most common syndrome in our cohort being present in 94 patients (34 male, 60 female), with 42 (15 male, 27 female) patients diagnosed with Juvenile myoclonic epilepsy (JME), 23 (9 male, 14 female) with Juvenile absence epilepsy (JAE) and 20 (9 male, 11 female) with childhood absence epilepsy (CAE). EEG studies in all patients showed generalised epileptiform activity. CONCLUSIONS: More women than men were diagnosed with generalised epilepsy. Tonic clonic seizures were the most common seizure type reported. EGTCSA was the most frequent syndrome seen. Gender differences were evident for JAE and JME as previously reported and for EGTCSA, which was not reported to date, and reached statistical significance for EGTCA and JME.     

EEG markers of future cognitive performance in the elderly

This exploratory follow-up study investigated whether EEG parameters can predict future cognitive performance. Forty elderly subjects, ranging from cognitively unimpaired to those with Alzheimer disease underwent EEG registration at baseline and neuropsychological examination at both baseline and follow-up. We assessed relations between EEG measures and future cognitive performance (i.e., global cognition, memory, language, and executive functioning) controlling for age, follow-up time, and baseline cognitive performance. Regression models were constructed to predict performance on the Cambridge Cognitive Examination, a widely used tool within dementia screenings. Baseline EEG measures, i.e., increased theta activity (4-8 Hz) during eyes closed and less alpha reactivity (8-13 Hz) during eyes open and memory activation, indicated lower global cognitive, language (trend significant), and executive performance at follow-up. A regression model combining baseline cognitive and EEG measures provided the best prediction of future Cambridge Cognitive Examination performance (93%). EEG and cognitive measures alone predicted, respectively, 43% and 92% of variance. EEG and cognitive measures combined provided the best prediction of future cognitive performance. Although the "cognition only" model showed similar predictive power, the EEG provided significant additional value. The added value of EEG registration in the diagnostic work-up of dementia should be further assessed in larger samples.     

Eye closure sensitivity in juvenile myoclonic epilepsy and its effect on prognosis

PurposeTo investigate eye closure sensitivity (ECS) in the EEGs of patients diagnosed with juvenile myoclonic epilepsy (JME) and its relationship to prognosis.MethodsWe included 76 JME patients with a minimum follow-up of one year and evaluated a total of 254 EEGs to obtain evidence of ECS. The patients were grouped according to their response to treatment, and these subgroups were compared in relation to ECS and other clinical and EEG features.ResultsThere were 12 patients (15.8%) with poor prognosis who showed resistance to appropriate anti-epileptic drug treatment, 15 (19.7%) patients with pseudo-resistance, and 49 (64.5%) patients with good prognosis. The EEGs of only four of the patients displayed pure ECS (5.3%), and only one of these exhibited poor prognosis. Furthermore, 11 patients (14.5%) had both ECS and photosensitivity, and two of these patients exhibited poor prognosis. Thus, neither pure ECS nor ECS with photosensitivity correlated with poor prognosis. A family history of epilepsy and focal findings on the EEG was correlated with poorer prognosis.ConclusionsECS is a rare EEG finding in JME and does not appear to be a marker for poor prognosis.