EEG value in cases of epileptic seizures in early phase of stroke]

The aim of our work was to assess the usefulness of EEG in patients with seizures in acute phase of stroke. EEG patterns of 54 patients with epileptic seizures at the onset of stroke were evaluated: 45 of ischaemic, 6 of haemorrhagic origin and 3 with lacunar stroke as confirmed by CT or MR examination. Out of 40 patients, who had a single or multiple seizures at the onset of stroke, EEG revealed focal slow waves in 90% and in 22.5% they were accompanied by interictal epileptiform discharges. None of those patients had recurrent seizures during the time of hospitalisation irrespectively of applying antiepileptic drugs. In the remaining 14 patients prolonged disturbances of consciousness were observed. EEG examination revealed simple partial status epilepticus (SE) in 10 and complex partial SE in 4 of them. In 11 of those patients EEG disclosed fragments of periodic lateralized epileptiform discharges (PLED) interrupted by seizure activity. The findings indicate that in patients with seizures in the acute phase of stroke EEG examination is very helpful in making the proper therapeutic decision by recognizing the SE. The introduction of antiepileptic drugs is generally not necessary in stroke patients with single seizures.     

Epileptic seizures in post-stroke patients

We were investigating the frequency of early (within 30 days) and late (within 12 months) poststroke epileptic seizures, in our group consisting of 483 patients with stroke (423 cases of ischaemic stroke and 60 cases of haemorrhagic stroke) and without prior diagnosis of epilepsy. In 28 (5.8%) cases early seizures were observed. The most common type of early seizures were generalised seizures, slightly less frequent were simple partial seizures. EEG usually showed focal slow waves or non-specific slowing of background activity. Among 195 one-year survivors late seizures occurred in 6 (3.1%). 5 of them had ischaemic stroke. 30 day and 12 months fatality in the group of patients with seizures was not significantly higher than in all stroke patients.     

Jeannette Stirling, Representing Epilepsy: Myth and Matter , Liverpool Univ. Press, Liverpool (2010) ISBN 978-1-84631-237-3 Hardcover, 256 pp. £65.00, US$95.00.

Metabolic disturbances are often associated with epileptic seizures, but the pathogenesis of this relationship is poorly understood. We describe the case of a 48-year-old man who presented with complex partial status epilepticus with visual seizures in the context of ketotic hyperglycemia. The EEG revealed a temporal epileptogenic focus and alterations were apparent on MRI in the acute phase and 4 months later. Very few cases of seizures in ketotic patients have been reported because ketone bodies have a protective effect against epilepsy. Seizures in hyperglycemia tend to be partial, and the only reports of visual seizures were due to occipital foci. Neuroradiological alterations have been reported in epileptic seizures, although usually in generalized seizures. The clinical, electrical, and imaging characteristics of this case are interesting and suggest that partial seizures can also cause long-term neuronal damage.     

Childhood epilepsy uncontrolled by phenytoin: clinical and electroencephalographic study.

Nine cases of childhood epilepsy manifesting motor convulsions uncontrolled despite high levels of phenytoin (PHT) were studied clinically and electroencephalographically. These cases consisted of five cases of partial seizures without impairment of consciousness, two cases of partial seizures (occasionally generalized seizures beginning locally), one case of predominantly unilateral seizures, and one case of generalized tonic-clonic seizures. the onset of seizures was at a rather early age, between 3 months and 9 years, and under 3 years of age in eight cases. All cases had single or multiple, cortical epileptic foci in EEG. The projection of spikes was localized to a rather limited area. Seizures of these patients were frequent. All cases, except one, did not respond to other medication. Convulsive seizures with cortical focal spike foci in EEG uncontrolled despite high levels of PHT were thought to have poor responsiveness to not only PHT itself, but also to other anticonvulsants.     

EEG and CT findings in poststroke epilepsy

The present study was undertaken to assess the diagnostic value of CT in patients with poststroke epilepsy, related to EEG in revealing the factors contributing to the development of epileptic fits. The EEG and CT results were evaluated in 50 patients with poststroke epilepsy and compared with those of 50 patients without epilepsy after stroke. Cortical and extensive lesions involving the cortex were more frequent among patients with poststroke epilepsy. Sparing of certain parts of cerebral cortex was observed within vasogenic lesion. This type of change was only found in the poststroke epilepsy group and may be responsible for development of epileptic fits. It seems that CT has a higher diagnostic value than EEG in evaluating the risk of development of poststroke epilepsy.     

Facial Asymmetry in Partial Epilepsies

Fifty-six consecutive epileptic patients with partial seizures (30 temporal, 26 extratemporal) and facial asymmetry were studied. Facial asymmetry was compared with EEG, radiologic, and other clinical findings. Thirty patients had a lesional epilepsy whereas 26 were considered cryptogenic. In lesional epilepsies, 60% of patients had EEG foci ipsilateral to the smaller hemiface and only 20% had EEG foci contralaterally. In the cryptogenic group, the EEG focus was ipsilateral in 50% and contralateral to the facial smallness in 46%. No differences were noted between temporal and extratemporal epilepsies. Early acquired cerebral lesions may modify development of the hemisphere involved, leading to a small ipsilateral hemiface and seizures originating from the same side.     

Epilepsy in vacuolating megalencephalic leukoencephalopathy with subcortical cysts.

Vacuolating megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a disorder characterised by acquired macrocephaly, developmental motor delay of varying degrees, slowly progressive cerebellar and pyramidal signs, and initially preserved intellectual function. More than 60% of the published cases had epileptic seizures. In this study, we analysed the seizures and EEG findings of nine patients with MLC. Six patients (66.6%) with moderate to severe neurological impairment had epilepsy, four with partial and two with generalised seizures. The EEG of five epileptic patients revealed epileptogenic foci over the temporal, frontal and parietal regions with variable predominance during waking and sleep. The facilitation of spike-and-wave paroxysms by eye closure, by intermittent photic stimulation and by hyperventilation were determined in four patients. Four patients also showed abnormalities in the background activity. In conclusion, we think that epilepsy is a significant component of MLC compared to the other leukodystrophies. The elucidation of the underlying molecular defect may explain the unusual pathogenetic relation between this leukoencephalopathy and the associated seizures.     

Seizures in childhood ischemic stroke in Taiwan

In this retrospective study, we collected clinical and radiographic data on children (age range, 1 month to 18 years) with symptoms and radiographic confirmation of seizure after ischemic stroke for the period of January 1996 to July 2006. Thirty-nine out of 94 children with ischemic stroke had poststroke seizures. Thirty-three out of 39 children with poststroke seizures had new onset seizures but only data of 28 were available. Infection was the most common etiology in the early poststroke seizure group (52.4%) but not in the late poststroke seizure group (0%). Infarction involving arterial ischemic stroke of anterior circulation were the most common in both the early poststroke seizure (61.9%) and the late poststroke seizure group (57.1%). Epilepsy was the most common sequelae in both the early poststroke seizure (38.1%) and late poststroke seizure group (100%). Children who had initial focal neurological sign (100% vs. 38.1%; P=0.007) or the focal cortical dysfunction on EEG (85.7% vs. 33.3%; P=0.029) were prone to develop late poststroke seizures. Late poststroke seizures had a high risk of developing poststroke epilepsy (100% vs. 38.1%; P=0.007). We conclude that seizures commonly occur in childhood ischemic stroke. Most poststroke seizures developed at an early stage. Infection was the most common etiology that caused early poststroke seizures in childhood ischemic stroke. Initial focal neurological signs and focal cortical dysfunction on EEG are risk factors for developing epilepsy. Poststroke seizures did not affect mortality, but there was a significant difference in normal outcome and epilepsy between those with or without poststroke seizures.     

Physiologic all-night sleep in patients with severe forms of epilepsy

100 all night sleep records in 90 patients with various forms of epilepsy and 10 patients with syncope were analyzed. There were 10 patients with generalized epilepsy, 41-with partial epilepsy with complex symptomatology and temporal foci, 23--with mixed seizures and frontal focal changes and 16 patients with partial epilepsy with simple seizures and various location of EEG foci. Normal sleep pattern was present in 21% of cases. The most frequent changes of sleep pattern were: prolongation of sleep onset and the latency of the first episode of REM, instability of sleep stages and absence of sleep spindles. Interictal discharges appeared mostly in all sleep stages of NREM. 50% of epileptic patients showed focal spikes in REM. Nocturnal seizures occurred in 18 patients, in several of them very frequently.     

EEG findings after a cerebral territorial infarct in patients who develop early- and late-onset seizures

BACKGROUND: EEG findings are generally not considered to be very helpful for the diagnosis of poststroke seizures. PURPOSE: This retrospective study investigates the EEG characteristics in patients who develop seizures after a cerebral territorial infarct. PATIENTS AND METHODS: The study population consisted of 110 patients with seizures after a cerebral territorial infarct (12 with early- and 98 with late-onset seizures) and 275 without. All 110 patients had an interictal EEG after their first seizure. The EEG patterns after the stroke were compared between those available from 69 patients who developed seizures and those from 275 who did not. Also the EEG patterns after the seizure (n = 110) were compared to those in the poststroke group without subsequent seizures. RESULTS: Periodic lateralized epileptic discharges (PLEDs) on the EEG after stroke were only found in 5.8% of the patients with early- and late-onset seizures. They were absent in the stroke group without seizures. Frontal intermittent rhythmic delta activities (FIRDAs) were observed in 24.6% of the seizure group, compared to 1.1% in the control group. Diffuse slowing occurred also significantly more often in the former (21.7%) compared to the latter group (5.1%). Normal EEG findings were seen in 53.8% of the stroke patients without seizures, compared to 8.5% in those with seizures. The incidence of focal slowing was the same in both groups. Similar findings were observed when comparing the EEG patterns of the patients after the first poststroke seizure to those of the stroke group without subsequent seizures. In patients with early-onset seizures, PLEDs or FIRDAs were present in 25% each. FIRDAs and diffuse slowing were significantly more frequently observed on the poststroke EEGs of patients who developed late-onset seizures. CONCLUSIONS: FIRDAs, PLEDs and diffuse slowing are the most frequent EEG findings in patients with early-onset seizures. Patients with FIRDAs and diffuse slowing on the poststroke EEG have a high risk to develop late-onset seizures, while the chance is reduced in those with normal EEG findings.     

Seizures in multiple sclerosis

PURPOSE: In patients with multiple sclerosis (MS), epileptic seizures occur more frequently than in the general population. The aim of this study was to analyze clinical characteristics of epilepsy in patients with MS, potential correlation between the semiology of seizures, EEG and magnetic resonance imaging (MRI) findings in these patients, as well as to examine the response to anticonvulsant therapy. METHODS: In a series of 268 consecutive patients with definite MS hospitalized at the Institute of Neurology, Belgrade, we identified 20 (7.5%) patients with seizures or epilepsy. All patients with seizures or epilepsy were submitted to standard EEG and brain MRI with gadopentetate dimeglumine. RESULTS: In four patients, epilepsy occurred 1-5 years before other clinical manifestations of MS. Eight patients had seizures only during MS relapses (provoked seizures). In two of them, seizures were the only manifestations of relapse. In 12 patients, seizures occurred regardless of the phase of MS (chronic epilepsy). In the majority of patients, seizures were partial with secondary generalization. Five patients experienced episodes of status epilepticus, and they all had dementia. Abnormal EEG pattern was found in 11 patients. Brain MRI disclosed cortical-subcortical lesions in nine patients and focal cortical atrophy in one, whereas in the remaining patients, findings were inconclusive. Probable EEG-MRI-seizure type correlation existed in 10 patients. CONCLUSIONS: Our data suggest that epilepsy may represent an initial symptom of MS and a single clinical manifestation of a relapse, and further support the assumption of the existing correlation between the presence of cortical-subcortical lesions and epileptic seizures or epilepsy in patients with MS.     

脑电偶极子分析在痫灶切除术中的定位价值

目的探讨长程视频脑电监测和偶极子分析在痫灶切除术中的定位价值。方法对35例开颅痫灶切除术患者术前行常规脑电和长程视频脑电监测,脑电痫性放电进行偶极子分析,并与手术中硬膜下电极记录的脑电相对照。结果35例患者视频脑电图监测异常35例,有痫性放电者35例;常规脑电图异常28例,有痫性放电者18例;行常规脑电图监测无典型癫痫发作出现。两者之间脑电异常率、痫性放电阳性率、典型临床发作率都有统计学意义。以术中硬膜下电极记录为标准,头皮脑电偶极子定位异常放电灶的准确率为97%,切除病灶病理检查异常率86%。偶极子定位误差一般<15mm。结论长程视频脑电监测和头皮脑电偶极子定位癫痫起源灶可为开颅痫灶切除手术提供有价值的信息。     

Periodic lateralized epileptiform discharges: association with seizures.

The clinical features and EEGs of 45 consecutive patients (40 adults and 5 children) who had periodic lateralized epileptiform discharges (PLEDs) were reviewed to determine the relationship between seizures and PLEDs. Focal encephalitis and ischemic stroke were the most frequent underlying processes for adult patients. All of the children, but only six of the adults, had long-lasting cerebral disorders whereas the remaining adults had acute or subacute illness. There were 38 patients (84.4%) experiencing a seizure disorder. Twenty-six of them had their first seizure during their acute illness, as the pattern of PLED was encountered. Eight cases had status epilepticus, and seven of them had epilepsia partialis continua. Nineteen patients had a recent seizure in the day when PLEDs were observed but not during EEG recording; 12 patients had their seizures within 10 days before the observation of PLED. PLEDs were grouped into three categories with respect to their extensions: lateralized to one hemisphere (n = 22), localized in one region (n = 17) and being prominent over one side with contralateral spread (n = 6). The last group was found to be more closely associated with frequent seizures or status epilepticus than the other two groups. Our results showed that PLEDs were highly correlated with recent seizures in the majority of the patients. These EEG findings may be considered as a manifestation of an increased neuronal excitability caused by different etiologies; but not an ictal pattern.     

Psychomotor epilepsy and psychosis

The EEG findings in waking, sleep, and sphenoidal electrode recordings in 96 patients with partial epileptic seizures with complex symptoms, who, after a median interval of 18 years developed paranoid/hallucinatory psychosis, were compared with the findings from a group of patients without psychosis, who had had the same type of epilepsy in median 24 years. There were no significant differences between the two groups with regard to median age at onset of epilepsy or complex partial seizures, age, or duration of epilepsy at time of examination. the psychotic patients had a significant preponderance of temporal medio-basal spike foci, recorded on the sphenoidal electrode, indicating deep temporal lobe dysfunction as an important factor in the pathogenesis of psychosis. A significant higher frequency of bilateral and multiple spike foci, together with a significant frequency of slow-wave admixture to the waking background EEG activity, indicated more extensive and severe epileptogenic lesions in the psychotic patients. There was no correlation between psychosis and unilateral EEG foci in either temporal lobe.     

Epileptic seizures following ischaemic cerebral infarction

Summary Clinical, CT and EEG findings of 100 consecutive patients suffering from epileptic seizures following hemispheric cerebral infarction were evaluated retrospectively. All patients were followed up for an average of 49 months. Twelve patients suffered from cardiogenic brain embolism, 20 had an occlusive disease of the internal cerebral artery. Forty-seven patients had a single middle cerebral artery infarct, 6 each a posterior cerebral artery or watershed infarct. CT showed lacunes in only 6 cases, 8 had multiple larger infarcts and 27 were normal. Seventy-six patients suffered from generalized seizures, 54 from partial fits, predominantly focal motor seizures. Seventy-one patients had their first seizure within the 1st year after stroke, 30 within 2 weeks after the infarct. The interval between stroke and the first epileptic fit exceeded 1 year in the remaining 29 cases. If the first fit occurred in the acute phase after stroke, the risk of further ones was significantly lower than when the first fit occurred in the chronic stage. The frequency of fits mainly depended on the occurrence of epileptic potentials in the EEG and the interval between stroke and the first seizure. During follow-up 27 patients suffered a recurrent stroke, and 52 patients died. Cardiac failure was the predominant cause of death; only 4 patients died as a consequence of an epileptic fit.     

The value of EEG in the investigation of postapoplectic epilepsy

During the 5 years 1979-1983 61 patients within the county of Frederiksberg developed postapoplectic seizures after the age of 60. Of these patients EEG was performed on 48. These EEG's were compared to the EEG's from 25 patients of the same age with epilepsy due to cerebral tumors 33 patients with acute stroke and 24 patients with stroke sequelae who had not experienced seizures. Slow wave activity and foci were seen more often among patients with acute stroke than among patients with postapoplectic seizures whereas paroxysmal activity occurred less often in patients with acute stroke than among patients with postapoplectic seizures patients with stroke sequelae and patients with seizures due to cerebral tumours. Patients with stroke sequelae with proven hemispheric localization had focal abnormalities more often than patients with postapoplectic seizures but apart from this EEG difference between patients with postapoplectic seizures and patients with stroke sequelae or seizures due to brain tumours were not found. In 12 of the patients with postapoplectic seizures and in 20 of the patients with stroke sequelae without seizures EEG at the time of the acute stroke was available. Differences between patients with and patients without seizures were not found neither at the time of the acute stroke nor at the time of readmission due to stroke sequelae or due to onset of seizures. It is concluded that a routine EEG is without value in the diagnosis of postapoplectic seizures in the elderly.     

Epileptic prodromal manifestations and episodic affective symptoms: nonspecific complaints or non-convulsive status epilepticus?

Subjective unspecific complaints presage in some patients with epilepsy a following overt epileptic seizure. It has to be considered whether these epileptic prodromal states are simple partial seizures (epileptic aura) or a status epilepticus non convulsivus. Three patients with epilepsy of different classification and etiology were studied. Their interictally occurring unspezific complaints, the clinical examination and EEG with simultaneous videorecording were documented. In these three cases the results led to the conclusion that the epileptic prodromal states were the expression of a status epilepticus non convulsivus. The management and possible therapeutic intervention are discussed.     

Study on early-onset benign occipital seizure susceptibility syndrome.

We prospectively studied the early-onset benign occipital seizure susceptibility syndrome to confirm the benign prognosis. The patients were 37 children followed for more than 2 years after meeting the following criteria on the first examination: (1) normal development before the onset of epilepsy, (2) onset between 1 and 8 years of age, (3) normal brain MRI and cranial CT findings, (4) partial seizures manifested both initial ictal vomiting and tonic eye-deviations, and (5) normal background activity with or without epileptic EEG foci regardless of location. The incidence and clinical characteristics of seizures, response to treatment, and EEG findings were analyzed. The total number of seizures ranged from one (n = 6) to 27 times, with a median of five times. Recurrent prolonged attacks resistant to antiepileptic drugs were recognized in 15 children, who had earlier onset of epilepsy and more frequent complications than the remaining 22 children. Interictal EEG revealed occipital foci in 26 children, 17 of whom later revealed a shift in predominant foci. At the final examinations, 28 patients had been seizure-free for at least 2 years. The clinical picture of this syndrome ranges from those with a few seizures to those with recurrent prolonged seizures initially resistant to antiepileptic drugs despite ultimate remission by 12 years of age.     

卒中后继发癫痫患者常规与动态脑电图检查的比较分析

目的研究卒中后继发癫痫患者常规脑电图(electroencephalography,EEG)与动态脑电图(ambulatory electroencephalography,AEEG)的特点。方法观察40例急性卒中后继发癫痫患者的病灶分布、范围、癫痫发作形式及频数,所有病例作EEG及AEEG检查,将检查结果分为正常、轻度异常、中度异常及重度异常进行统计分析。结果40例研究对象的病灶分布主要在颞叶、额叶及丘脑,癫痫发作类型主要为全面性强直阵挛发作。EEG检查异常的比率为47.5%,其中轻度异常占异常总数的52.6%,中度和重度异常占47.4%;AEEG检查异常的比率为80%,其中轻度异常占异常总数的12.5%,中度和重度异常占87.5%,AEEG较EEG检查的异常比率明显增高,具有统计学差异。结论AEEG可显著提高卒中后癫痫发作患者的脑电异常检出率,其检查结果对指导临床治疗具有一定的价值。     

Persistent worsening of stroke sequelae after delayed seizures.

Though the role of cerebral ischemia as an etiologic factor for epilepsy is accepted, the effect of seizures on stroke sequelae has received little attention. We describe 10 patients with poststroke partial epileptic seizures that were followed by persistent worsening of the previous neurologic deficit. Of 38 other patients with poststroke seizures who were examined during the same period, eight suffered transient neurologic worsening (Todd's phenomenon). Persistent worsening was associated with longer seizures and longer partial seizures before generalization. Risk factors, age, sex, other seizure features, and characteristics of previous stroke were irrelevant to developing persistent worsening of stroke sequelae. None of the patients with persistent worsening showed a new lesion or an extension of the previous ischemic area on computed tomography or magnetic resonance imaging, except one who had a first hemorrhage that spared the cortex and who suffered a second hemorrhage, which was lobar. Persistent worsening of a neurologic deficit following a seizure in patients with previous stroke may not be uncommon and may be due to a direct effect of the seizure itself on the infarcted area.