New-onset mesial temporal lobe epilepsy in a 90-year-old: clinical and EEG features.

Although there is a peak in the incidence of epilepsy in the elderly compared with the general population, complex partial seizures represent less than 15% of the seizure types reported. We report on a 92-year-old woman with a 2-year history of daily complex partial seizures. Prolonged video/EEG recording showed bilateral anterior mesial temporal interictal spikes, which predominated on the left, and two typical seizures arising from the left temporal area. Cranial MRI scanning showed multiple lacunar infarcts without temporal lobe involvement or mesial temporal atrophy. Our case appears to be oldest patient in the literature with newly diagnosed mesial temporal lobe epilepsy confirmed by video/EEG recording.

Asynchronous and asymmetric burst-suppression in a patient with a corpus callosum lesion.

INTRODUCTION: Burst suppression is seen in the electroencephalograms of patients receiving high doses of pentobarbital. In such circumstances, burst suppression is characterized by bilaterally synchronous and symmetric bursts of electrical activity followed by intervals of attenuation. METHODS: We report on a case of asymmetric and asynchronous pentobarbital-induced burst suppression that occurred after a corpus callosum lesion sustained during trauma. CONCLUSIONS: To our knowledge, this is the first such reported human case of asymmetric and asynchronous pentobarbital-induced burst suppression. These findings suggest that the corpus callosum may be involved in the synchronization of the burst-suppression pattern.

Sensitivity and specificity of asymmetric recall on WADA test to predict outcome after temporal lobectomy.

Some reports suggest that the intracarotid amobarbital test (IAT) is useful for predicting good seizure outcome after temporal lobectomy. The sensitivity, specificity, and predictive value of the IAT in this condition has not been previously studied. We designed this study to establish the value of memory recall asymmetry on the IAT as a predictor of outcome after temporal lobectomy. We studied memory recall on the IAT in 108 consecutive patients with intractable epilepsy who underwent presurgical evaluation for temporal lobectomy and had at least 1 year follow up after surgery. At a level of 30% asymmetry of recall, specificity for favorable outcome (Engel Class I and II) was 100% (95% confidence interval [CI], 85 to 100), sensitivity 51% (95% CI, 40 to 62), positive predictive value 100% (95% CI, 92 to 100), and negative predictive value 34% (95% CI, 23 to 47). At the same level of asymmetry, specificity for seizure-free outcome (Engel Class I) was 88% (95% CI, 68-95), sensitivity 37% (95% CI, 40 to 64), positive predictive value 87% (95% CI, 71 to 96), and negative predictive value 38% (95% CI, 27 to 50). Asymmetric recall on the IAT is highly specific but not very sensitive in predicting outcome after temporal lobectomy.

Usefulness of ictal and interictal 99mTc ethyl cysteinate dimer single photon emission computed tomography in patients with refractory partial epilepsy.

PURPOSE: Ictal perfusion single photon emission computed tomography (SPECT), using HMPAO, has been shown to localize epileptic foci in approximately 90% of studies. Unfortunately, HMPAO decomposes rapidly, precluding the performance of ictal studies. Ethyl cysteinate dimer (ECD) is a SPECT perfusion agent recently approved by the Food and Drug Administration. After preparation, this compound is stable for approximately 6 h. facilitating the performance of ictal studies. METHODS: In a prospective, open-label, uncontrolled, non randomized study, we evaluated the potential benefits of the use of 99mTc-ECD SPECT for lateralization of the epileptic focus. Ten consecutive adult epilepsy surgery candidates were studied with ictal and interictal 99mTc-ECD SPECT. RESULTS: The mean delay between seizure onset and ictal SPECT injection was 23.2 s. The mean seizure duration was 84.1 s. Ictal studies agreement between the epilepsy focus and area of hyperperfusion was evident in 8 of 10 cases. In one case, SPECT was lateralized in a patient with bilateral temporal lobe epilepsy (TLE); however, hyperperfusion was observed on the same side of that particular seizure. In another case, there was location disagreement. Interictal SPECT showed focal hypoperfusion in three cases. CONCLUSIONS: 99mTc-ECD proved to be an optimal tracer for ictal studies. Although this is a small series, the results of ictal and interictal findings using 99mTc-ECD are similar to those reported with 99mTc-HMPAO. Because 99mTc-ECD has a longer decomposition time, true ictal studies are easier to obtain. This new tracer will probably allow the use of ictal SPECT to become widely accepted in most epilepsy centers.

Atypical triphasic waves associated with the use of pentobarbital.

To report a case in which triphasic waves developed during pentobarbital treatment. Pentobarbital coma is indicated in status epilepticus, refractory to other anticonvulsants, and in certain neurologic conditions in order to decrease brain metabolism. At high doses of pentobarbital, the EEG shows a typical burst-suppression pattern, while at low doses, diffuse slowing. Triphasic waves have not been reported in association with pentobarbital. A 54-year-old female underwent surgery for giant ophthalmic aneurysm clipping. Due to tearing and bleeding of the carotid artery, a clamp was placed, an external-internal carotid artery bypass was done, and the patient was started on pentobarbital. The patient remained comatose, the EEG showed a burst-suppression pattern, and the pentobarbital level was 30.5 micrograms/dl. One week later, the patient was still comatose, the EEG showed generalized triphasic waves with anterior predominance, and the pentobarbital level was 11 micrograms/dl. One day later, the patient was awake, and the EEG was normalized. The patient made a complete recovery. Triphasic waves may be seen in patients on pentobarbital. It is important to recognize this finding in patients on pentobarbital due to status epilepticus. This pattern should not be misinterpreted as 'electrical' status epilepticus.

Epilepsy after central nervous system infection: clinical characteristics and outcome after epilepsy surgery.

Fifty-six (5.8%) patients with partial epilepsy secondary to central nervous system (CNS) infection (meningitis = 20 and encephalitis = 36) were identified from 963 patients studied with prolonged video-EEG monitoring. Twenty-seven (48.2%) patients had unilateral mesial temporal lobe epilepsy (UMTLE), 9 (16.1%) had bilateral mesial temporal lobe epilepsy (BMTLE), and 20 (35.7%) had neocortical epilepsy (NE). Younger age at infection and prolonged latency between the time of infection and development of epilepsy were predictive factors for UMTLE. Predictors for BMTLE were late age of infection and short latency between infection and epilepsy development. Development of NE was associated with short latency between infection and epilepsy, and younger age at infection. When outcome after temporal lobectomy was compared between the UMTLE group and a control group with UMTLE without history of CNS infection, no statistically significant differences were found. Central nervous system infection may lead to epilepsy, which in many cases, is generated by a single portion of the brain. In such cases, epilepsy surgery should be considered, as in patients without history of CNS infection.

Value of full-field visual evoked potentials for retrochiasmal lesions.

Some abnormalities in the P100 on monocular stimulation have been said to indicate retrochiasmal abnormalities. This study was undertaken to evaluate the reliability of visual evoked potentials (VEPs) for this purpose. We retrospectively reviewed VEPs that could be interpreted as indicative of a retrochiasmal lesion, based on an amplitude asymmetry of >50% between the P100 recorded on the left and right occipital regions. The abnormality had to be present on both left and right monocular stimulation (uncrossed pattern). Studies were conducted in accordance with the guidelines of the American Electroencephalographic Society. Findings on magnetic resonance (MR) imaging were analyzed. For comparison, we also studied a control group of 30 patients with normal VEPs. During a 16-month period, we identified 15 patients who fulfilled the aforementioned criteria and who had undergone an MR scan of the brain. Eight scans were normal and seven were abnormal. Of the seven abnormal scans, five revealed multiple periventricular white matter lesions in both hemispheres suggestive of multiple sclerosis: one a single punctate white matter lesion in the left frontal corona radiata, and one multiple white matter lesions in the basal ganglia, brainstem, and cerebellum but not in the hemispheres. In the control group with normal VEPs, nine had at least one hemispheric lesion on MR scans. This yielded a positive predictive value of 33%. The negative predictive value was 70%, sensitivity 36%, and specificity 68%. Because of a high rate of false positives, full-field VEPs were not reliable in predicting retrochiasmal lesions.

Usefulness of prolonged video-EEG monitoring in the elderly.

The diagnosis of epilepsy in the elderly can be difficult. We sought to determine whether video-EEG monitoring (VEEG) is useful in the diagnosis and management of elderly patients with epilepsy. We reviewed the medical records of 20 consecutive patients, over 60 years of age, selected from a total of 1423 patients referred over a five year period for VEEG evaluation for epilepsy. The usefulness of VEEG was assessed by comparing changes in (a) the diagnosis and treatment of these patients before and after VEEG, and (b) the assessments made by an epileptologist who reviewed medical records before and after receiving results of VEEG. Compared to the initial diagnosis by the referring physician, VEEG resulted in changes in either the diagnosis or treatment in 11/20 patients based on the results of VEEG. The epileptologist was able to correctly assess the diagnosis and treatment of 16/20 patients without knowledge of the VEEG results. In 4/20 cases, the VEEG provided additional information to the epileptologist. In selected elderly patients, VEEG is useful in establishing the diagnosis of epilepsy, and may change the management of these patients.

Preictal pseudosleep: a new finding in psychogenic seizures.

BACKGROUND AND OBJECTIVE: The diagnosis of psychogenic seizures (pseudoseizures) may be difficult and usually rests on video-EEG monitoring. We observed that pseudoseizures often arise out of a state that we termed preictal pseudosleep. The objective of this study was to investigate this potential new sign in pseudoseizures. METHODS: We prospectively studied all patients who underwent noninvasive monitoring over a 10-month period. Patients were monitored for a duration of 1 to 19 days (mean 4.9), and were divided into two groups: pseudoseizures and epileptic seizures. Patients with both conditions were excluded. Preictal pseudosleep was defined as a state that resembled normal sleep by behavioral criteria alone (i.e. patient motionless and eyes closed), while EEG showed evidence of wakefulness (alpha rhythm, active EMG, and rapid eye movement). This state had to be sustained for at least 1 minute before clinical onset. RESULTS: Patients had 1 to 25 (mean 7) clinical events recorded. Preictal pseudosleep was seen in 10 of 18 patients with pseudoseizures and in none of 39 patients with epileptic seizures, yielding a sensitivity of 56% and a specificity of 100% for pseudoseizures. CONCLUSION: Because of a high specificity, preictal pseudosleep may be a useful adjunctive finding to support the diagnosis of pseudoseizures.

Psychogenic seizures in children: long-term analysis of 43 cases.

Forty-three patients exhibiting psychogenic seizures with onset before the age of 16 years were studied. All patients underwent intensive electroencephalography and video-electroencephalography monitoring. Thirty-two were female and 11 male. Mean age of the population at seizure onset was 12.4 years (range, 5 to 16 years). Twenty-one patients (48.8%) were taking anticonvulsants. Neurologic past history was abnormal in nine cases. Family history of epilepsy was found in 15 cases (34.9%). Median seizure frequency was one seizure every 5 days. Clinical characteristics of the seizures varied. However, unresponsiveness with generalized violent and uncoordinated movements involving the whole body (n = 19) or with generalized trembling (n = 11) were the most common features. Neuropsychological testing, carried out in 22 cases, failed to show major abnormalities in most of the cases. Significant personal and family distress was found in most of the cases. An important impact on patient's quality of life was evident when the seizures were present as compared to the seizure-free periods. There were no statistically significant predictors of clinical outcome.

Choreiform movements associated with the use of valproate.

OBJECTIVE: To describe the association of choreiform movements with the use of valproic acid. DESIGN: Case series. PATIENTS: Three patients who developed chorea during long-term treatment with valproic acid. All patients had severe brain damage; one had a preexisting unilateral vascular lesion in the caudate nucleus. At the time chorea developed, two patients were also receiving phenytoin sodium. RESULTS: Chorea developed between 30 minutes and 3 hours after ingestion of valproic acid, and the duration of the episodes varied between 30 minutes and 8 hours. The episodes of chorea occurred frequently for several days followed by asymptomatic periods lasting several weeks. Choreic movements involved the head, mouth, tongue, trunk, and limbs bilaterally in two cases and contralaterally in the patient with the caudate lesion. In one case, it was necessary to withdraw valproic acid treatment, while in the other two cases, replacement of valproic acid by divalproex sodium sprinkles presumably decreased peak concentrations and resulted in resolution with no recurrence of the chorea. CONCLUSIONS: Valproic acid-associated chorea occurred in patients with severe epilepsy and brain damage. It may occur after several years of valproic acid use and may be more likely to develop if valproic acid is taken together with phenytoin. Because valproic acid-associated chorea seemed to be dose related, avoiding excessive fluctuations of serum levels by the use of divalproex sodium sprinkles may be an effective solution in these cases.

Predictive value of induction of psychogenic seizures by suggestion.

Induction by suggestion has previously been reported to be effective in the diagnosis of psychogenic seizures (PS). However, the sensitivity and specificity of this procedure has not previously been studied. Results of induction of PS by suggestion were analyzed in 93 patients with purely PS. The diagnosis of PS was based on the recording of a clinical event on video-electroencephalography, the absence of clinical or electroencephalography the absence of clinical or electroencephalographic evidence of epilepsy, and the subsequent followup and withdrawal of anticonvulsants supporting the diagnosis of PS. A control-group was composed of 20 patients with epilepsy in which induction was tried. Both groups were comparable for age, sex, and educational level. Induction was performed following a standardized protocol. The test was carried out placing a colored patch on the neck. The test was considered positive when the induced clinical events were typical, according to a witness familiar with the patient's seizures. Induction was positive in 72 of 93 cases with PS and in none with epilepsy. Sensitivity of this test for the diagnosis of PS was 77.4%, specificity 100%, positive predictive value 100%, and negative predictive value 48.7%.

Clinical and EEG asymmetries in juvenile myoclonic epilepsy.

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.

Circling seizures in a case of juvenile myoclonic epilepsy.

Circling seizures (CS) have been described in association with focal lesions as well as with generalized EEG discharges. We report 1 patient with juvenile myoclonic epilepsy (JME) who developed CS. There were no focal findings on clinical examination, EEG, or imaging studies. We propose that CS in this patient may represent a profound asymmetry in expression of an idiopathic generalized epilepsy rather than a partial condition.

Systemic lupus erythematosus associated with use of valproate.

A 30-year-old man with long-standing localization-related epilepsy and mental retardation had seizures that were partially controlled with valproate (VPA) 500 mg four times daily. Routine examination showed severe thrombocytopenia with mild leukopenia and chronic low-grade hemolytic anemia. Pertinent laboratory results included positive ANA, rheumatoid factor, anti-NIA, circulating immune complexes, and antihistone antibody. The patient was treated with high dosage prednisone with partial improvement, but continued to have exacerbations at lower dosages. Fourteen months later, VPA was discontinued, and rapid improvement ensued. Prednisone was subsequently discontinued, and the patient has now maintained normal platelet counts for 18 months.

Psychogenic seizures in adults: a longitudinal analysis.

The clinical characteristics, psychosocial background, neuropsychological testing, clinical and social outcome were analysed in 93 adults with psychogenic seizures (PS). Thirteen (14%) were males and 80 (86%) were females. Mean age was 31.7 years (range 16 to 55 years). Lack of responsiveness associated with motor activity was the most common finding. Neuropsychological testing done in 46 cases revealed hysteroid traits and coping mechanisms and depression to be the most prevalent underlying problems. History of sexual abuse was evident in 10 (10.7%) cases. Social impact analysis revealed that of 62 patients who were working at the onset of PS, 34 were not working at the time of the diagnosis of PS. In 25 cases, PS were the reason for not working. After a mean follow-up of 60.7 months done in 63 patients, 16 (25.4%) patients were seizure-free. There were no obvious significant predictors of poor prognosis.

Effects of monotherapy and polytherapy on the blink reflex in epileptic patients.

We performed the blink reflex (BR) in 20 normal volunteers, 13 epileptic patients receiving antiepileptic drug (AED) monotherapy, and 13 epileptic patients receiving AED polytherapy. Comparison of R1, ipsilateral and contralateral R2 and VIIth nerve latencies in the three groups showed no statistically significant differences R1 and VIIth nerve latencies among the three groups. There were statistically significant differences between the polytherapy group and the monotherapy and control groups in comparisons of ipsilateral and contralateral R2. There were no significant differences between the monotherapy group and the control group for ipsilateral and contralateral R2. We hypothesized that AED polytherapy might interfere with synaptic transmission in the polysynaptic pathway of the blink reflex, prolonging the latency of R2. These results provide further evidence of the pathophysiologic effects associated with polytherapy in epileptic patients.

Paroxysmal pain as sole manifestation of seizures.

A developmentally normal 4-year-old white female who presented with pain in the right hand as the only manifestation of epilepsy is reported. Two years later, she developed complex partial seizures following right-hand pain. Computed tomography and magnetic resonance imaging were unremarkable. Prolonged ambulatory electroencephalography (EEG) as well as video-EEGs with ictal pain episodes failed to reveal abnormalities. Only a full night video-EEG performed after antiepileptic drug withdrawal demonstrated 2 right-hand pain episodes followed by a complex partial seizure with ictal epileptiform activity on the scalp EEG in the left parasagittal area, rapidly generalized and interictal discharges in the C3-P3 area. This patient had a very unusual presentation of epilepsy.