Successful epilepsy surgery without intracranial EEG recording: criteria for patient selection.

Twenty-two patients with intractable complex partial seizures (CPS) were treated with temporal lobectomy. Eighteen of 22 (82%) are seizure-free while receiving medication, with a mean follow-up time of 4 years. In each case, the clinical seizure pattern, interictal and ictal scalp EEG, magnetic resonance imaging (MRI), neuropsychological testing, and results of the intracarotid amobarbital procedure (IAP) converged to indicate a localized abnormality.

Characteristics of medial temporal lobe epilepsy: II. Interictal and ictal scalp electroencephalography, neuropsychological testing, neuroimaging, surgical results, and pathology.

Sixty-seven patients with temporal lobe epilepsy without circumscribed, potentially epileptogenic lesions, who were studied with intracranial electrodes and who became seizure free following temporal lobectomy were retrospectively evaluated with regard to preoperative scalp electroencephalographic (EEG) findings, neuropsychological test results, neuroimaging findings, results of surgery, and pathology of resected tissue. Interictal scalp EEG showed paroxysmal abnormalities during prolonged monitoring in 64 patients (96%). These were localized in the anterior temporal region in 60 (94%) of these 64 patients.

Specificity in the correlation of verbal memory and hippocampal neuron loss: dissociation of memory, language, and verbal intellectual ability.

Fifty-nine patients with temporal-lobe epilepsy (28 left, 31 right) completed the Boston Naming Test (BNT), verbal subtests of the Wechsler Adult Intelligence Scale-Revised, and the Logical Memory Subtest of the Wechsler Memory Scale (WMS) before surgery. Performances by patients with left temporal seizure foci were significantly more impaired than those of patients with right seizure foci on the WMS Logical Memory subtest and the BNT. After surgical removal of the mesial temporal lobe structures, two blinded observers established volumetric cell densities for hippocampal subfields CA1, CA2, CA3, the hilar area, and the granule cell layer of area dentata.

The debt of neuropsychology to the epilepsies.

Both neuropsychology and psychology in general have been enhanced markedly by brain-behavior models derived from the study of the epilepsies. A significant body of neuropsychological concepts originated or were confirmed through epilepsy-based treatment and research. These concepts include the peri-Rolandic homunculus, the role of the hippocampal-temporal lobe complex in cognitive memory, hemisphere plasticity for speech in childhood, the intracarotid amytal procedure for determining hemisphere memory patency, and hemisphere-based models of cognition confirmed through human commissurotomy.

Quantitative magnetic resonance imaging in temporal lobe epilepsy: relationship to neuropathology and neuropsychological function.

Magnetic resonance images (MRIs) were obtained from 25 patients with medically refractory epilepsy of temporal lobe origin (12 on the left, 13 on the right) and 14 right-handed control subjects. The hippocampi and temporal lobes were traced by computer on successive coronal images and the resulting measurements of area were summed for each region. The left and right hippocampi were symmetrical in the control subjects; however, for patients the hippocampus was smaller on the side of the seizure focus.

Parietal lobe epilepsy: diagnostic considerations and results of surgery.

Eleven patients, evaluated between 1983 and 1988, with parietal lobe seizure origin as determined by circumscribed lesion detection in all and successful surgery in 10, were retrospectively evaluated in terms of clinical seizure characteristics and electroencephalographic (EEG) findings. Seven of 11 patients reported auras prior to seizures. In 4 patients, auras were lateralized somatosensory sensations, but in 1 they were ipsilateral to the side of seizure origin, and in 2 they had only occurred many years previously when seizures began.

Intracranial, intraaxial, space-occupying lesions in patients with intractable partial seizures: an anatomoclinical, neuropsychological, and surgical correlation.

Fifty of approximately 250 patients evaluated for intractable partial seizures were shown to have a space-occupying lesion detected with radiographs and/or neuroimaging. Twenty-eight males and 22 females had a mean age at seizure onset of 13 years and a mean duration of seizures of 11 years. All patients had closed-circuit television with EEG monitoring and complete neurologic and neuropsychological assessment.

The neural substrate of memory impairment demonstrated by the intracarotid amobarbital procedure.

The intracarotid amobarbital sodium (Amytal) procedure (IAP) was performed for 46 patients with temporal lobe epilepsy (21 with left seizure foci; 25 with right seizure foci). After anteromedial temporal lobectomy, neuronal densities were established for hippocampal subfields CA1, CA2, and CA3; the hilum; and the dentate granule cell layer. Intracarotid amobarbital procedure memory results were related to CA3 neuronal loss only.

Verbal memory impairment correlates with hippocampal pyramidal cell density.

Thirty-five patients with medically refractory epilepsy localized to the temporal lobe (18 left, 17 right) completed the verbal Selective Reminding Test before surgery. Verbal memory impairments existed before surgery regardless of the lateralization of the seizure focus, but patients with left temporal seizure foci were significantly more impaired. After surgical removal of the mesial temporal lobe structures, 2 blinded observers established volumetric cell densities for hippocampal subfields CA1, CA2, CA3, the hilar area, and the granule cell layer of the area dentata.

Mixed speech dominance in the Intracarotid Sodium Amytal Procedure: validity and criteria issues.

An international survey was conducted of 55 epilepsy surgery programs (from 10 countries) that conduct the Intracarotid Sodium Amytal Procedure (IAP). Respondents reported large differences in the prevalence of mixed speech dominance (MSD) in their patient populations. These differences are shown to be due in part to disagreement about the criteria for the demonstration of speech production from the non-speech-dominant hemisphere.

Retrograde amnesia following unilateral temporal lobectomy.

Remote memory performance was assessed in a carefully matched sample of temporal lobectomy subjects and normal controls. Left temporal lobectomy subjects exhibited a consistent pattern of remote memory disturbance. Right temporal lobectomy subjects performed at the same level as normal controls.

Postcallosotomy language impairments in patients with crossed cerebral dominance.

Language impairments were reviewed retrospectively in patients who underwent partial or total corpus callosum section for medically refractory secondary generalized epilepsy. Postoperatively, four of 32 patients had clinically significant language impairments that were not present prior to the operation. All involved primarily verbal output (speech and writing) and spared verbal comprehension.

Olfactory lateralization and identification in right hemisphere lesion and control patients.

This study investigated olfactory lateralization and identification in right hemisphere lesion and control patients. Significant group differences were found for olfactory and trigeminal lateralization and identification on unilateral and double simultaneous stimulation. In the control group, significantly greater than chance accuracy was found for lateralization and identification, whereas in the lesion group, significantly greater than chance accuracy was found for identification but not for lateralization.

Olfactory functioning and callosotomy: a report of two cases.

Two callosotomy patients with presumably intact anterior commissures were evaluated on a battery of olfactory tasks including sensitivity, discrimination, memory, identification, cross-modality matching, bilateral summation (dirhinic vs. monorhinic thresholds), and localization of odorants. One case was evaluated both pre- and post-surgery.

Unilateral displacement in the olfactory sense: a manifestation of the unilateral neglect syndrome.

Unilateral neglect is a syndrome primarily occurring with right hemisphere--particularly right parietal lobe--brain damage and involving the failure to respond to stimuli presented to the left side of the body and space. Unilateral displacement (a less severe manifestation of the neglect syndrome) involves the accurate identification of a stimulus, but the displacement or mislocalization of that stimulus to the opposite side of the body and space. This study investigated two major theories of unilateral neglect utilizing the primarily ipsilaterally innervated olfactory sense.

MMPI indices in the identification of patients evidencing pseudoseizures.

Data are presented on the clinical utility of two Minnesota Multiphasic Personality Inventory (MMPI) indices, the Pseudo-Neurologic (Pn) Scale developed by Shaw and Matthews and the configural rule system developed by Wilkus et al. for the prediction of pseudoseizures. Particular attention is given to base rates, hit rates, and error rates in the analyses.

The nature of unilateral neglect in the olfactory sensory system.

This study investigated two major theories of unilateral neglect utilizing the ipsilaterally innervated olfactory sense. The sensory theory states that unilateral neglect is due to a diminished or attenuated sensory input. The representational theory states that unilateral neglect is due to a disordered internal representation, which is not dependent on sensory input.

Corpus callosotomy for epilepsy. II. Neurologic and neuropsychological outcome.

Eighteen uncontrolled epileptic patients had neuropsychological evaluation before and after partial or total corpus callosotomy. In patients with early-onset seizures and signs of severe unilateral CNS dysfunction, callosotomy produced no deficits and several improvements. All patients whose language-dominant hemisphere did not control their dominant hand had impairments in some aspect of speech and language function after callosotomy.

Corpus callosotomy for epilepsy. I. Seizure effects.

Twenty-two patients were analyzed 2 or more years after corpus callosum section (9 partial, 13 total). Forty-one percent had class 1 outcome (elimination of secondarily generalized and complex partial seizures), 32% had class 2 outcome (elimination of secondarily generalized seizures), and 27% had class 3 outcome (no appreciable change). Total section was twice as effective in abolishing secondarily generalized seizures as was partial section (77% versus 35%).

Hyperreligiosity in temporal lobe epilepsy: redefining the relationship.

Seventy-six subjects with the primary diagnosis of complex partial seizures with a unilateral temporal lobe focus were examined for the presence of hyperreligiosity. Fifty-one subjects had a left temporal lobe seizure focus and 25 had a right temporal lobe seizure focus. In addition to the temporal lobe epilepsy (TLE) groups, two reference groups were also examined.

Results of a nationwide Veterans Administration Cooperative Study comparing the efficacy and toxicity of carbamazepine, phenobarbital, phenytoin, and primidone.

In 1985 a 5-year multicenter Veterans Administration Cooperative Study was completed that compared the efficacy and toxicity of phenobarbital, carbamazepine, phenytoin, and primidone in a double-blind prospective study design. A total of 622 patients, either previously untreated or undertreated, were entered into the study. Strict exclusion criteria limited confounding factors such as drug or alcohol abuse.

Behavioral toxicity associated with antiepileptic drugs: concepts and methods of assessment.

The BTB designed for the VA Epilepsy Cooperative Study is a conceptually organized and practical set of test procedures that can be utilized to assess change in the areas of motor integration, visual perception, speech and language, and mood that might be attributable to AED therapy. If the data warrant, these categories can be compressed into motor, attention-concentration, and mood. The unique methodological advantages of the VA Epilepsy Cooperative Study provide an opportunity to determine empirically the occurrence of behavioral toxicity for specific AED.

Odor perception in temporal lobe epilepsy patients with and without temporal lobectomy.

The investigation employed monorhinic (single nostril) olfactory testing to decide whether patients with unilateral anterior temporal lobe resection (N = 16) and patients with unoperated temporal lobe epilepsy (N = 18) have impaired ability to detect, remember, and identify odors. A shape memory task accompanied the odor memory task for comparison. The lobectomy patients showed a minor bilateral depression of absolute sensitivity but still fell within the clinically normal range.

Effects of simultaneous vs sequential stimulus presentation on memory performance following temporal lobe resection in humans.

This study examines the differential effects of simultaneous vs sequential stimulus presentation on performance of a visuo-spatial memory task in patients following unilateral temporal lobectomy for relief of complex-partial seizures. Eleven subjects with surgical resection of the left temporal lobe, 13 subjects with surgical resection of the right temporal lobe, and 12 normal controls were examined. Results indicate that both the Right and the Left surgical groups were impaired on the visuo-spatial memory task employed.

Complex partial status epilepticus: a depth-electrode study.

Of 87 patients with complex partial epilepsy who were evaluated with depth electrodes, 8 developed complex partial status epilepticus (CPSE). Seizures originated extratemporally in all 8 patients. Frontal lobe onset was established in 4 patients and was probable in 1 more.