Scalp EEG differs in temporal and extratemporal complex partial seizures

We compared scalp ictal EEG in complex partial seizures originating in extratemporal regions with seizures originating in the temporal lobe. All patients were seizure-free for 2 or more years after appropriate cortical resection confirming focus of seizure onset. The electroencephalographer reviewing seizures was blind to patient identity. Extratemporal seizures were shorter, more difficult to lateralize, and had postictal slowing less often. Confident lateralization of seizure onset could not be made in 19% of the seizures, usually because onset was diffuse or artifact obscured the seizure. When lateralization judgments were thought possible, lateralization errors occurred in only 3% of the seizures. Five percent of the seizures had no detectable scalp ictal changes.     

Febrile seizures in patients with complex partial seizures

Febrile seizures occurred in 14 of 155 (9%) out-patients with complex partial seizures. Twelve patients had prolonged or recurrent febrile seizures, convulsive status epilepticus or a transient postictal neurological deficit. Febrile seizures were associated with perinatal abnormalities, an earlier onset of epilepsy and with a poor seizure control. Recurrent febrile seizures or those with complicating features are associated with an unfavourable therapeutic outcome in adult patients with complex partial seizures.     

The psychotherapy of patients with complex partial seizures.

The direct neurological effect of complex partial seizures (CPS) is described, as is the psychological and interpersonal impact of the disorder, with emphasis on the iterative nature of the process. A model for the psychotherapy of CPS patients is presented that is based on an understanding of the neurological changes and continuous interaction between these changes and the psychological demands of adaptation.     

Cerebral metabolism and depression in patients with complex partial seizures.

Twenty-three patients with complex partial seizures were evaluated with 18F-2-deoxyglucose positron emission tomography and with the Beck Depression Inventory. Five of 10 patients with left and zero of eight with right temporal electroencephalographic foci had depressive symptoms; one of five patients with poorly localized electroencephalographic foci also scored in the depressed range. Temporal, frontal, caudate, and thalamic normalized glucose metabolic rates among five patients with depressive symptoms and well-localized left temporal epileptogenic regions were compared with five patients without depressive symptoms but with similar electroencephalographic characteristics. Multifactorial analysis of variance yielded a significant nonlateralized mood by region interaction. Of nine individual regions compared, only inferior frontal cortex showed a significant difference in normalized regional metabolic rate between depressed and nondepressed patients. Metabolism in this region also distinguished patients with depressive symptoms from normal control subjects. Depressive symptoms in patients with complex partial seizures are associated with a bilateral reduction in inferior frontal glucose metabolism, compared with patients without depressive symptoms and normal control subjects. The frontal lobe hypometabolism observed in patients with depressions associated with epilepsy, Parkinson's disease, and primary affective disorder suggests that similar frontal lobe metabolic disturbances could underlie these conditions.     

The evaluation of patients with intractable complex partial seizures

Conceptual advantages, together with advances in both technique and technology, have considerably altered the approach to intractable epilepsy over the past two decades. Appropriate utilization of these advances allows our evaluation of patients with intractable seizures to be much more precise and specific than was once the case and allows us to improve considerably our ability to treat patients with intractable epilepsy. We propose an algorithm for the evaluation and treatment of patients with intractable complex partial seizures. Other forms of intractable epilepsy may benefit from similar diagnostic and therapeutic approaches.     

Electrophysiologic pathologic correlations in patients with complex partial seizures

We studied interictal activity and site of ictal onset in 26 patients with complex partial seizures of temporal lobe origin. All patients had prolonged electrocorticographic recordings from subdural electrode arrays placed both over the convexity and beneath the temporal lobe. We found a significant correlation between the epileptogenic focus and the type of pathologic lesion found at time of surgery. Macroscopic lesions strongly tended to have an epileptogenic focus on the lateral surface of the temporal lobe; patients with only microscopic abnormalities tended to have an epileptogenic focus in the mesial/basal region of the temporal lobe.     

Microwave oven injuries in patients with complex partial seizures

Microwave ovens are often recommended as a safe cooking alternative for persons with epilepsy. We report four patients who suffered serious burns to their hands while handling microwave-heated liquids during a complex partial seizure (CPS). Injuries were due to the contact of the skin with a very hot container. The fact that all patients held on to the hot containers despite being burned and that they did not remember experiencing any pain at the time of the accident indicates that neither high temperatures nor pain will prevent patients who are having a CPS from suffering this type of injury. Unfortunately, there is no foolproof way to prevent the individual from opening the oven and removing its contents during a CPS. The only solution for this problem is "prevention"-individuals with poorly controlled CPS should be cautioned about these risks. The use of microwave settings that permit the heating but not boiling of liquids and the use of gloves while heating food and liquids to scalding temperatures may minimize the risk of this type of injury.     

HIPDM-SPECT in patients with medically intractable complex partial seizures. Ictal study

Both interictal and ictal N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3,propanediamine -single photon emission computed tomography (HIPDM-SPECT) were performed in 16 patients with medically intractable complex partial seizures. Ictal HIPDM-SPECT localized epileptic foci in 13 of 14 patients with unilateral temporal focus and provided confirmative evidence of epileptic focus in 11 patients by demonstrating maximally increased regional cerebral perfusion (rCP) in epileptic foci that had shown decreased rCP in a previous interictal study. Ictal HIPDM-SPECT in two patients with bitemporal foci showed more complicated patterns consisting of slightly increased rCP in bilateral multifocal regions. Ictal HIPDM-SPECT was particularly useful for investigating epileptic foci, and correlation with simultaneously recorded ictal electroencephalograms provided further insight for localizing epileptic foci.     

Prognosis of chronic epilepsy with complex partial seizures.

Clinical features associated with a successful or unsuccessful response to high dose antiepileptic drug therapy were evaluated prospectively in 82 patients with chronic complex partial seizures. Complete seizure control was observed during high dose drug therapy in 18 patients at plasma concentrations of either 9-35 micrograms/ml phenytoin, 32 and 40 micrograms/ml phenobarbitone, 8 micrograms/ml carbamazepine, or a combination of 25 micrograms/ml phenobarbitone and 4 micrograms/ml carbamazepine. Patients who became free of seizures had a markedly lower number of three seizures (range: 1-29) in the year before the high dose treatment as compared to 40 seizures (range: 3-328) in patients with an increased or unchanged seizure frequency (p less than 0.0001). Complex partial seizures without automatism were found only in patients with complete seizure control (22%). Patients whose seizures remained uncontrolled more frequently gave a history of severe depression or psychotic episodes, clusters of complex partial seizures, two or more seizures per day, and an aura preceding the attack. The results suggest that taking a careful history will uncover clinical features associated with a successful or unsuccessful response to high dose antiepileptic drug therapy in an epileptic out-patient with chronic complex partial seizures.     

Nocturnal plasma prolactin rise in patients with complex partial seizures

We measured plasma prolactin and cortisol concentrations in 12 epileptic men with complex partial seizures during all-night polygraphic recording, with continuous video monitoring and sequential blood sampling at 30-minute intervals. There was a significant but moderate elevation of all-night mean plasma prolactin concentration (p < 0.001), but not of cortisol, in epileptics when compared with normal subjects studied in a similar fashion. The data obtained in this environmentally controlled study of males with complex partial seizure disorder indicate a disruption of prolactin regulatory mechanisms resulting in a modest elevation of plasma concentrations independent of ictal electrographic discharges.     

Benign infantile epilepsy with complex partial seizures

Benign infantile epilepsy with complex partial seizures is characterized by a high incidence of family history of benign childhood convulsions, normal development prior to onset, infantile onset, no underlying disorders, no neurological abnormalities, normal interictal EEGs, good response to treatment, and complete remission with normal developmental outcome. Seizures often occur in clusters, consisting of motion arrest, decreased responsiveness, staring or blank eyes mostly with simple automatisms, and mild convulsive movements associated with focal paroxysmal discharges, most frequently in the temporal area.     

Self-abatement of complex partial seizures

Seven of 71 patients with complex partial seizures claimed they were able to abate their seizures, while none of 18 with simple partial seizures were able to do so. Self-abatement exercises included highly stereotyped cognitive and physical components unique to the individual. Those who could abate their seizures had attained higher educational status, better social and vocational adjustment, and better psychological adjustment than did the control group of patients with epilepsy. The self-abatement group was also more likely to have right hemispheric electroencephalographic abnormalities. Characterization of the self-abatement group may be relevant to the selection of candidates for behavioral therapy for epilepsy.     

Computerized seizure detection of complex partial seizures.

In this study, we describe a computerized method that uses 3 quantified EEG features and discriminant analysis to automatically detect seizure EEG. The quantified EEG features were relative amplitude, dominant frequency and rhythmicity. Using EEGs recorded from intracranial electrodes, the seizure detection method was applied to consecutive non-overlapping 2-channel EEG epochs. A seizure detection sensitivity, ranging from 90% to 100%, was associated with a false positive detection rate of 1.5-2.5/h. The performance of the seizure detection method remained stable for EEG recorded over variable time periods.     

Extratemporal atrophy in patients with complex partial seizures of left temporal origin

Total cerebral, temporal lobe, hippocampal, caudate, and lenticular nuclei volumes were quantified from magnetic resonance images of 21 patients with left temporal lobe epilepsy and medically intractable complex partial seizures. These regional brain volumes were compared with the same measures in 19 controls. No significant differences in total cerebral, left temporal lobe, right temporal lobe, or total temporal lobe volumes were found. As expected, left hippocampal volumes were significantly smaller in the patients with epilepsy than in control subjects. The left hippocampus-to-right hippocampus volume ratio was significantly lower in patients than in control subjects. In addition to left hippocampal volumes, mean left thalamic, left caudate, and bilateral lenticular volumes were significantly smaller in the patients with epilepsy than in control subjects. The left-to-right thalamic volume ratio was also significantly lower in the patients with epilepsy compared with control subjects, but there were no significant group differences in caudate or lenticular ratios. These results show that medically intractable temporal lobe epilepsy is associated with volume loss in brain structures outside the presumably involved hippocampus. The pathophysiological significance of our findings is uncertain. They could be related to the underlying cause of the disorder. However, volume loss also may reflect damage due to involvement of these structures in recurrent seizure activity.     

Computer enhancement of scalp-sphenoidal ictal EEG in patients with complex partial seizures

Color topographic maps of scalp/sphenoidal ictal EEG records were computer-generated in 5 patients with medically refractory complex partial seizures of suspected temporal lobe origin. Seven ictal EEG records were analyzed by parsing them into a series of 1.28 sec epochs. User-interactive, computer techniques were utilized to replace eye movement and other artifactual segments in the peri-ictal records with nearby uncontaminated EEG segments. Artifact replacement techniques were designed to minimize or eliminate EEG discontinuities in those epochs in which artifact was removed. Significance probability maps consisting of z scores were constructed by comparing theta band power for each 1.28 sec epoch composing the peri-ictal period with the mean and standard deviation of theta power computed from a pre-ictal baseline period consisting of 50-75 epochs. The resulting maps were compared with available independent clinical measures in order to validate their usefulness. The independent measures consisted of non-invasive data (visual impressions of raw scalp/sphenoidal ictal EEGs and positron emission tomography) and invasive data (depth ictal recordings, pathological findings in resected temporal lobes, and surgical outcome). Ictal topographic maps appeared to either confirm or provide new localizing information in all 5 patients. In 3 of 5 patients, several seconds of localized theta suppression preceded localized theta augmentation during the peri-ictal period. The transition between the 2 states was very rapid (approximately 2 sec). The spatial locus of suppression was always in agreement with the spatial locus of augmentation. In general, the maps were considerably easier to interpret than the raw scalp/sphenoidal ictal EEGs: (1) Localized theta suppression in the maps was not evident from visual inspection of the raw ictal scalp/sphenoidal EEG. (2) Clear localized theta augmentation in the maps occurred well before the appearance of unambiguous phase reversals in the raw scalp/sphenoidal ictal EEG. (3) Mapping data were correctly lateralizing in 1 patient in whom visual interpretation of the raw scalp/sphenoidal ictal EEGs was considered non-localizing but often suggestive of a seizure origin in the hemisphere contralateral to that implicated by depth recordings, PET, and pathological data. These results suggest that topographic mapping of scalp/sphenoidal ictal EEGs in patients with complex partial seizures may eventually prove to be a useful adjunct to the interpretation of raw ictal recordings.     

Lorazepam: a controlled trial in patients with intractable partial complex seizures

Lorazepam was studied in a double-blind, placebo-controlled, crossover trial in eight patients with frequent partial complex seizures refractory to therapy with a combination of standard anticonvulsant drugs. Concomitant antiepileptic drugs were maintained at therapeutic serum levels throughout the study, and concentrations of lorazepam were monitored. Following an 8-week baseline observation, patients were randomly assigned to placebo or lorazepam (1 mg BID). The dose was increased biweekly until seizures stopped or unacceptable side effects occurred. Eight weeks later, patients were crossed over, and the same escalating dose paradigm was followed. When seizure frequency during the last 2 weeks of each treatment was compared, seven of eight patients had fewer seizures on lorazepam, and the eighth had decreased seizure duration (a significant difference: p less than 0.01, two-tailed sign test). Blood level data suggest a narrow therapeutic window, with seizure improvement occurring at concentrations of 20-30 ng/ml and side effects at greater than 33 ng/ml. Lorazepam appears to be a useful adjunct in refractory partial complex seizure therapy. It should not be stopped abruptly, as an increase in seizure frequency may result.     

Regional brain glucose metabolism in patients with complex partial seizures investigated by intracranial EEG.

We performed interictal 18F-2-fluoro-2-deoxy-D-glucose positron emission tomography (18FDG-PET) studies in 57 patients with complex partial epilepsy (CPE), not controlled by medical treatment and considered for surgical resection of their epileptic focus. A precise localization of the epileptic focus was obtained in 37 of these patients with a combination of subdural and depth electrodes. We visually inspected the metabolic images; we also measured glucose consumption in a number of brain regions and compared the values with those obtained in 17 normal controls. Eighty-two percent of the 57 patients had an area of glucose hypometabolism on the 18FDG-PET images. Six patients had a frontal epileptic focus, 3 of them had a frontal lobe hypometabolism. Twenty-six patients had a unilateral temporal lobe focus and all of them displayed a temporal lobe hypometabolism. The asymmetry was more pronounced in the lateral temporal cortex (-20%) than in the mesial part of the temporal lobe (-9.6%). In each cortical brain region on the side of the epileptic focus (except the sensorimotor cortex), glucose consumption rate was lower than in the contralateral region or than in controls. No differences could be found between patients with a seizure onset restricted to the hippocampus and patients with a seizure onset involving the hippocampus and the adjacent neocortex. Divergent metabolic patterns were obtained in 5 patients with bilateral temporal seizure foci. Combined with other non invasive techniques (EEG, neuroradiology), PET contributes increasingly to the selection of patients with CPE who could benefit from surgical treatment.(ABSTRACT TRUNCATED AT 250 WORDS)