Value of magnetic resonance imaging-based measurements of hippocampal formations in patients with partial epilepsy.

OBJECTIVE: To determine the occurrence of magnetic resonance imaging-detected hippocampal atrophy (HA) in patients with partial epilepsy (temporal and extratemporal, cryptogenic, or symptomatic). Magnetic resonance imaging-detected HA has been demonstrated to be both sensitive and specific for hippocampal sclerosis in cryptogenic temporal lobe epilepsy. DESIGN: Patients' hippocampal formations were measured on a computerized system using T1-weighted, 5-mm contiguous magnetic resonance coronal images made perpendicular to the hippocampus long axis. Hippocampal atrophy was defined on the basis of a normative asymmetry index and correlated with the epileptogenic focus defined by clinical, electroencephalographic, and magnetic resonance imaging (apart from HA) localizing data. PATIENTS AND CONTROL SUBJECTS: Seventy patients with intractable complex partial seizures of temporal, extratemporal, or undefined origin and 21 healthy control subjects. RESULTS: Hippocampal atrophy was present in 70% of patients with cryptogenic temporal lobe epilepsy (TLE) (n = 40), 44% of patients with symptomatic TLE (n = 9), 29% of patients with extratemporal epilepsy (n = 14), and 6% of unclassified patients (n = 16). In the cryptogenic TLE category, HA was marked and usually concordant (93%) with electroencephalographic lateralization. Hippocampal atrophy was often mild in the extratemporal epilepsy category. With the use of a wider confidence interval (+/- 3.1 SD instead of +/- 2.2 SD), HA specificity for TLE increased to 93%, HA specificity for lateralizing cryptogenic TLE reached 96%, and HA sensitivity for cryptogenic TLE stood almost unchanged (68%). We found a link between early convulsions and HA occurrence. CONCLUSIONS: Hippocampal atrophy is a marker for TLE. Dual pathologic findings are detected in 44% of symptomatic TLE cases. Mild HA is rarely associated with extratemporal epilepsy. Magnetic resonance imaging-based hippocampal volumetric analysis is a useful method to localize the origin of partial complex seizures.

Pursuit gaze and the occipitoparietal region. A case report.

A patient lost smooth pursuit gaze to the side opposite a right occipitoparietal hemorrhage. Saccadic gaze was preserved. Pursuit gaze broken by saccades was present toward the side of the lesion. Optokinetic nystagmus (OKN) was defective when a tape was moved toward the patient from the hemianopic fields. Within two weeks, the contralateral pursuit gaze defect had cleared; however, the visual field and OKN defects and the ipsilateral pursuit gaze abnormality persisted.

Association of ipsilateral motor automatisms and contralateral dystonic posturing: a clinical feature differentiating medial from neocortical temporal lobe epilepsy.

BACKGROUND: Clinical features that may help to differentiate medial temporal lobe epilepsy (MTLE) from neocortical temporal lobe epilepsy (NTLE) are lacking. OBJECTIVE: To investigate the localizing and lateralizing value of the association of ipsilateral motor automatisms and contralateral dystonic posturing in patients with medically refractory temporal lobe epilepsy. PATIENTS AND METHODS: Videotapes of 60 patients with well-defined MTLE, NTLE, or both were reviewed to assess the presence and the localizing value of unilateral dystonic posturing associated with motor automatisms. RESULTS: Twenty-eight of the 60 patients exhibited unilateral dystonic posturing. This sign was observed in patients with MTLE and NTLE. It was mostly contralateral to the seizure focus in patients with MTLE and exclusively ipsilateral in patients with NTLE. Unilateral motor automatisms occurred in 26 of the 60 patients with MTLE or NTLE. It was predominantly ipsilateral to the seizure focus in patients with MTLE and exclusively contralateral in patients with NTLE. The association of ipsilateral motor automatisms and contralateral dystonic posturing was found in 14 patients with MTLE but in none of the patients with NTLE. Two patients who had medial and neocortical seizure onset also exhibited this clinical feature. This association was not significantly correlated with the postoperative outcome in patients with MTLE. CONCLUSIONS: The association of ipsilateral motor automatisms and contralateral dystonic posturing may help to differentiate MTLE from NTLE with a reliable lateralizing value. This clinical association may reflect a specific pattern in the spread of the ictal discharge.

Headache as an epileptic manifestation.

In two cases, depth electrode studies and behavioral recordings indicated that headache was a clinical manifestation of ictal activity. The epileptogenic focus was found in the right limbic system, and right temporal lobectomy relieved the headaches.

Jumping Frenchmen of Maine.

The "Jumping Frenchmen of Maine" were described by George Beard in 1878. They had an excessive startle response, sometimes with echolalia, echopraxia, or forced obedience. In 1885, Gilles de la Tourette concluded that "jumping" was similar to the syndrome that now bears his name. Direct observations of jumpers have been scarce. We studied eight jumpers from the Because region of Quebec. In our opinion, this phenomenon is not a neurologic disease, but can be explained in psychological terms as operant conditioned behavior. Our cases were related to specific conditions in lumber camps in the 19th and the beginning of the 20th century.

The lateralizing and localizing value of adversion in epileptic seizures.

We studied 24 patients who had adversion as the first clinical manifestation of seizures. Seizures were recorded with depth electrodes as part of the evaluation for possible surgery for epilepsy. Head rotation did not help to lateralize the epileptic focus clinically, because deviations occurred ipsilaterally to the EEG focus in some patients, and because some patients had head rotation in either direction despite a unifocal epileptogenic abnormality. Furthermore, no cortical localization was consistently linked to either direction or degree of adversion. Adversion has no consistent lateralizing or localizing value.

Naloxone and focal epilepsy: a study with depth electrodes.

Intravenous injections of naloxone (0.8 to 2.4 mg) were given to patients with focal epilepsy who had had electrodes implanted in cortical and subcortical structures. There were no changes in interictal spike activity, responses to electrical stimulation, of frequency of spontaneous seizures. These data do not support the hypothesis that opiate peptides are involved in human focal epilepsy.

Sleep and temporal lobe epilepsy: a case study with depth electrodes.

We studied a patient with hippocampal epilepsy who had frequent nocturnal and diurnal seizures. Depth electrode recording showed that focal seizure discharges in the right hippocampus were of shorter duration in REM and non-REM sleep. However, awakening, especially from REM sleep or shortly after a REM period, facilitated the occurrence of a generalized seizure. There was no ultradian fluctuation in frequency or duration of seizure during diurnal recording. Night terrors (but not nightmares) disappeared after right temporal lobectomy, suggesting that pavor nocturnus was an ictal manifestation in this case.

Sleep spindles in the human hippocampus: normal or epileptic activity?

Spindles of 12-14 Hz were recorded in the hippocampus of 13 epileptics during sleep. This activity was more prominent in patients in whom the hippocampal region was not the site of the primary focus and in whom the electrical activity was normal during wakefulness. Spindles were more numerous during stage 2 non-rapid-eye-movement sleep, especially in patients who had seizures in this stage. It is postulated that this activity is either a normal activity of human brain or an evoked response of the hippocampus to an epileptic afferent discharge. In either case, hippocampal spindles may contribute to the triggering of nocturnal seizures.

Basic science and clinical aspects of procaine HCl as a limbic system excitant.

The literature in animals and humans which indicate that systemic procaine HCl activates limbic tissue is reviewed. Studies in cats which suggest that procaine excites limbic cells by reducing neural inhibition are then described. Evidence that power spectral analysis of high frequency EEG bands (omega or 31-55 cps) in the temporal cortical EEG reflects degree of limbic (amygdala) excitation in animals and humans is reviewed. Studies in cats are described which show that procaine selectively increases omega band activity in the amygdala and temporal cortex in a dose related fashion which parallels dose related increases in amygdaloid neural activity. Preliminary results of combining intravenous procaine and omega band analysis of scalp EEG in humans to predict therapeutic response to carbamazepine in borderline personality and affective disorder patients are then described. The effects of procaine on omega are compared to the effects of direct electrical stimulation of human limbic system in complex partial seizure patients undergoing assessment for temporal lobectomy. The results tentatively support the hypothesis that some psychiatric patients have hyperexcitable limbic systems, and those that do, show a positive behavioural response to carbamazepine.

Nocturnal sleep recording in partial epilepsy: a study with depth electrodes.

It has been known for centuries that sleep and epilepsy have strong reciprocal influences. This is true for all kinds of epilepsies, although the nature of this influence varies quite markedly for each type. This extensive literature cannot be reviewed here, but some recent applications of these early studies will be given.

Multiple subpial transection: report of 7 cases.

7 cases of pure multiple subpial transection (MST) without associated cortical resection, for treatment of pharmaco-resistant partial epilepsy localized in highly functional cortical area, are reported. The transections were performed following the technique described by Morrell. The follow-up period ranged from 1 to 4 years. MST induced no significant neurological handicap: only 2 patients experiencing a transitory sensory-motor deficit and with total recovery within 1 month. With respect to seizures, 5 patients were improved with a decrease in seizure frequency of 100, 95, 75, 60 and 40%, respectively. Complex partial seizures changed postoperatively into simple partial seizures in 1 case. In conclusion, this procedure seems to be adequate, although no statistically significant results are available at this time. In our series, we believe failures could be attributed to either a very restricted area of transection or to an incorrect delimitation of the epileptic focus.

Localizing and lateralizing value of epileptic symptoms in temporal lobe epilepsy.

The symptoms and signs associated with all stages of a temporal lobe seizure may be helpful in determining both the localization and lateralization of seizure onset. Auras, when present, may be very suggestive of temporal lobe onset and may further localize to a mesiobasal or lateral temporal lobe site of onset. During the ictus, automatisms and motor phenomena may be highly indicative of temporal lobe seizure activity and may even help lateralize the discharge. In the post-ictal period, motor paresis and aphasia are helpful in lateralization. Video E.E.G. data has provided extensive information on the utility of ictal symptomatology in seizure localization. Thus, the seizure semiology provides important adjunctive information in evaluating patients for epilepsy surgery and should be concordant with information obtained from ictal EEG, neuroimaging and neuropsychology.

Postictal aphasia and paresis: a clinical and intracerebral EEG study.

BACKGROUND: We examined the lateralizing value of postictal language and motor deficits and studied their underlying mechanisms. PATIENTS AND METHODS: The total sample consisted of 35 patients (26 temporals, 8 frontals, 1 parietal) with a good postsurgical outcome (Engel's class I and II). Postictal examination was blindly reviewed on videotapes. In 15 cases (29 seizures), postictal language manifestations were analyzed in relation with the diffusion of the epileptic discharge recorded by intracerebral EEG. Language dominance was determined by the intracarotid amobarbital test. RESULTS: Postictal aphasia was observed only when (1) seizure originated in the dominant hemisphere and (2) ictal activity spread to language areas (Wernicke and/or Broca areas). When the epileptic focus was in the nondominant hemisphere, no postictal aphasia was observed even if there was secondary generalization of ictal activity affecting the language areas of the dominant hemisphere. Postictal motor deficits also had a strong lateralizing value even when seizures were secondarily generalized. CONCLUSION: Postictal aphasia in temporal epilepsies and postical motor deficits in temporal and extra temporal epilepsies provided excellent lateralizing information. Postictal deficits appear to be the result of inhibitory mechanisms induced by previous ictal activity of the structures related to these functions.

Relative localizing value of common tests used in the preoperative investigation of epileptic patients.

We have compared the relative localizing value of common tests in the presurgical evaluation of epilepsy in 73 patients with depth electrode (SEEG) confirmed epileptogenic foci and excellent surgical outcome. We found the tests of abnormality (CT, amytal, neuropsychology) to be frequently non-informative and often discordant with SEEG. The EEG was concordant with the SEEG in 38% of cases and provided lateralization in 78%. EEG was less localizing than ictal behavior in frontals but not in temporals. The need for SEEG is rather evident in these results but could become attenuated by the development of the localizing power of scalp EEG.

[Epilepsy with aggressive behavior. Two cases with depth-electrodes recordings (author's transl)]. / Epilepsie avec manifestations agressives. Deux cas étudiés avec électrodes en profondeur.

Aggressive behavior is popularly thought to be frequently associated with the epileptic character and particularly temporal lobe disorders. However a thorough review of the literature fails to reveal any clear-cut evidence for this belief during inter-ictal periods. Some rare cases of ictal aggressive behavior have been reported but documentation has been difficult because of the previous lack of sophisticated observation equipment and because of difficulties of being present at the time of the seizure. Two rare but definite cases of epileptic aggressive behavior are presented with the help of videotape and E.E.G. recording on the scalp and with depth-electrodes.

[Research and surgical treatment of epilepsy]. / Investigations et traitement chirurgical des épilepsies.

The currently available surgical procedures for the treatment of epilepsy, from fundamental data to therapeutic results, including various means of investigation are reported. The work is based on a review of the literature and on the cases studied by the two teams from the Universities of Montreal and Bordeaux who share the same concept of epilepsy surgery. The patient groups of the two teams include 316 S.E.E.G., 214 cortectomies, 39 callosotomies and 2 multiple sub-pial transsections. In the first part, the authors attempt to demonstrate that the epileptic focus corresponds to the region where the seizures arise, that this focus is not directly comparable to the region where inter-ictal spikes are recorded and sometimes becomes autonomous from the causal lesion. The epileptic phenomenon has a definite harmful effect on cerebral functions and a probable self-aggravating potential. The second chapter summarizes the clinical data on which the indications and contraindications are based. These obviously depend on whether the intervention is intended to be curative or palliative. Various non-invasive and invasive investigations are then reviewed, according to their relative importance and the experience of each team. The main points developed are: the electroclinical correlations during seizures, the symptomatological data for differentiating between temporal and frontal lobe seizures, the contribution of M.R.I. in demonstrating the epileptogenic and epileptic lesions, the electrophysiological information suggesting that S.E.E.G. remains the most informative mean of investigation. The various methods of investigation of assessing electrical, functional (cerebral blood flow, metabolism) and morphological aspects of epilepsy, supply non-redondant findings about the localisation of the epileptic focus. The chapter on surgical techniques mainly discusses the various modes of implantation of subdural and intracerebral electrodes and reports the same rate of morbidity in both cases. Orthogonal teleradiography is still perfectly suited to the implantation of intracerebral electrodes. S.E.E.G. is still the most anatomically precise technique. However, in certain conditions, extraoperative E.Co.G. is more adequate. New surgical modalities have recently appeared such as the multiple subpial transsections which allow treatment of epileptic foci unapproachable by cortectomy and such as modified techniques of hemispherectomy, which by decreasing morbidity, renew interest in them. In the chapter on surgical results, the authors emphasize the methodological problems of evaluation that partly account for their wide variability. The results obtained with the various surgical modalities are reviewed. The outcome in cortectomies is discussed at length in terms of the data from the literature as well as the results reported by both teams.(ABSTRACT TRUNCATED AT 400 WORDS)

[Surgical treatment of epilepsy]. / La chirurgie de l'épilepsie.

The indications of surgery for epilepsy are: 1) resistance to medical treatment; 2) well-localized cortical focus, and 3) possibility of removing the focus without creating a significant functional deficit. Presurgical evaluation is initially clinical: correlations between the clinical manifestations recorded on videotapes and EEG tracings, neurological and neuropsychological examinations, intra-carotid amytal test. Interictal and, preferably, ictal EEG recording on the scalp and in depth is the fundamental procedure used to locate epileptogenic areas. The most reliable locating examination is the recording of a spontaneous seizure by means of implanted electrodes. Recent or old lesions responsible for epilepsy can be detected by arteriography, ventriculography, CT scans and, more recently, nuclear magnetic resonance. PET scan and SPECT are not commonly used. The ideal operation is cortectomy which gives the best long-term results (87 p. 100 in temporal lobe epilepsy). When cortectomy is not feasible, complete or partial (anterior two-thirds) callosotomy can be of considerable help in some forms of epilepsy with frequent falls and generalized seizures. On the whole, it seems that the surgical treatment of epilepsy is grossly underused.