Prevalence of psychosis in epilepsy as a function of the laterality of the epileptogenic lesion.

Retrospective analysis of the psychiatric diagnoses in a group of patients surgically relieved of medically intractable epilepsy tested the hypothesis that patients with left-sided temporal lobe epileptogenic lesions are at greater risk for the development of a so-called schizophrenic-like psychosis than are those with right-sided temporal lobe epileptogenic lesions. The data confirmed the hypothesis and also demonstrated an increased prevalence of sinistrals in the psychotic group. Thus, epilepsy involving the dominant hemisphere at the inception of the seizure disorder is the significant risk factors. The data also indicated that a psychosis is unlikely to develop in patients with other (nontemporal) forms of focal epilepsy. On the basis of these data and data from other studies, the prevalence of psychosis in patients with poorly controlled temporal lobe epilepsy was estimated to be approximately 10% to 15%.

The seizures of frontal lobe epilepsy. A study of clinical manifestations.

We describe ictal clinical manifestations of frontal lobe epileptic seizures in 22 patients. After examination of all ictal clinical data, 14 catergories of signs and symptoms were established. The validity of the ictal clinical data used was confirmed on the basis of 99 frontal lobe seizures recorded by tele-electroencephalogram or tele-stereo-electroencephalogram. The main conclusion is that the frontal lobe appears to be partially connected with motor acitivity.

Hemispheric lateralization of motor and speech functions after early brain lesion: study of 73 epileptic patients with intracarotid amytal test.

This study reports results of a bilateral intracarotid amytal test in 73 epileptic patients with medically intractable focal seizures. No right-handers but 50% of left-handers have a right dominance for speech in this particular population. Lateralization of cerebral speech functions, as well as manual preference, are dependent on the neurological disease and can shift conjointly or independently. We study the relationships of those shifts to different variables related to the cerebral pathology: age at onset and lateralization of epilepsy, extensive brain damage, neurological deficit.

Clinical consequences of corticectomies involving the supplementary motor area in man.

Three patients with well-mapped, circumscribed ablations of the medial part of the frontal lobe are reported. A specific clinical evolution in 3 stages was observed: (1) post-operatively there was global akinesia, more prominent contralaterally, with an arrest of speech; (2) recovery occurred suddenly but even then there was severe reduction of spontaneous motor activity contralaterally, an emotional type facial palsy and a reduction of spontaneous speech; (3) long after the operation the only sequela was disturbance of the alternating movements of the hands. The anatomical basis of these disorders appears to be a lesion of the supplementary motor area (SMA). Three main points have been discussed, namely: (1) the nature of the motor disorder which may be a disturbance of the function of the SMA in initiating and sustaining spontaneous and automatic motor activity; (2) the nature of the arrest of speech which appears not to be aphasic; the studies reported in the present paper do not support a left cerebral dominance for the SMA as suggested by previous studies; (3) the method of clinical examination appears to be important in distinguishing between spontaneous and voluntary motor and speech performance. Differences in method may account for differences between our findings and those reported in previous studies.

Motor consequences of motor area ablations in man.

Motor disorders reported in the present paper do not result from cortical ablations stricto sensu since some white matter was excised in every patient. However they appear to suggest that, as suggested by Walshe (1935), the central region and premotor area are a functional entity, i.e. they work as a whole. The extensive lesions of the premotor area, leaving untouched the motor region, have the same motor and tonic consequences as lesions limited to the central region. This point which appears specific for man does not imply that the premotor region subserves activities similar to those subserved by the central region. Rather it may suggest a deafferentiation of the central region, the consequences of which would be more important than is generally assumed. Extensive central or premotor lesions determine various tonic disorders: a well known spasticity, with exaggeration of the stretch reflex, associated with an increase in passive swinging of segments of limbs and in extensibility of joints. These two latter phenomena are usually defined as hypotonia. With premotor and precentral lesions the hypotonia disappears and a hemiplegic posture is observed. This hemiplegic posture is a dystonia which apparently does not result directly from the exaggeration of the stretch reflex. Anatomically it appears to result from lesions of both central and premotor regions. This is in agreement with Denny-Brown's (1966) contention that an extrapyramidal region lies rostral to the prerolandic sulcus. As suggested by Evarts (1973) motor regions appear to control automatic as well as voluntary movements. They probably play a role in the trophic function of muscle, since, despite rehabilitation, amyotrophy was present in every case reported in the present paper.

Can epileptologists without access to intracranial EEG use reliably the International League Against Epilepsy classification of the localization-related epileptic syndromes? A stereo-electroencephalographic study.

The goal of the present study was to investigate the reliability of clinical and electroencephalographic (EEG) criteria for the classification of localization-related epileptic syndromes as listed in the Proposals of Revised Classification of Epilepsies and Epileptic Syndromes 1989 (ICE). ICE distinguishes between multiple syndromes within epilepsies of a given lobe. Intracranial recordings were the main element in the development of the revised ICE. Considering that most epilepsy centers have no access to such invasive techniques for precise anatomic localization, it was of interest to assess how accurately the seizure origin could be determined from the scalp EEG and clinical data as reported in ICE. In this retrospective study, we compared the accuracy of the topographic diagnosis made by two groups of physicians evaluating the same patients-one group with and the other without access to results of stereo-EEG (SEEG). Medical files of 87 patients with intractable localization-related epilepsy were analyzed: 38 with frontal, 37 with temporal, 10 with parietal, and 2 with occipital lobe epilepsy were included in the study. All patients underwent previous SEEG and successful cortectomy. Minimum follow-up was 5 years. In most cases, noninvasive techniques and criteria suggested by ICE allowed topographic diagnosis of focal epilepsies according to brain lobe involvement. More detailed diagnosis, localizing the origin of critical activity within a lobe, was often unreliable. Further data are required for a definition of the epileptogenic zone. A spatiotemporal evaluation of critical events, including the intracranial EEG recording, remains the best method for topographic diagnosis of localization-related epilepsy.

Surgical therapy for frontal epilepsies.

We have described our 25 years experience concerning 100 patients operated on for frontal epilepsy. Results show that 55% of patients are practically cured of their seizures and that 76% benefited from cortectomy (reduction of more than 75% of seizures). These results are the worst in the total series of St. Anne. Reasons for success and especially failure were analyzed in detail: 1. SEEG methods gave good indications along three dimensions of the limits and borders of the cortical excision. 2. When clinical semiology and organization of ictal discharges give evidence for rapid bilateral discharge, with involvement of axial musculature and generalized tonic-clonic manifestations, experience shows that it is necessary to combine cortectomy with a section of the adjacent cortico-subcortical fibers of the corona radiata, as if propagation of ictal discharges were impeded if not interrupted by sectioning such fibers and the primary site were incapable of expressing itself clinically. 3. If the characteristics of seizures suggest the quasisimultaneous involvement of the two frontal lobes and the existence of bilateral multifocal epilepsy, we suggest that a systematized anterior callosotomy might lead to useful results. 4. Finally, we propose general criteria for indications and contraindications for surgery.

[Clinical symptomatology of epileptic seizures of temporal origin]. / Sémiologie clinique des crises épileptiques d'origine temporale.

Many discrepancies still exist in the description of clinical symptoms and signs attributable to a paroxysmal disorganization of temporal structures. They result from various methodological appraisals of clinical, electrophysiological and neuroradiological data concerning partial epilepsies. However a study of anatomo-electroclinical correlations in temporal seizures yield an easy pattern when the methods of elaboration, the criteria of validity and their meaning are strictly defined. An analysis of temporal seizures, recorded, filmed and described clinically in 300 patients having had a pre-surgical SEEG examination is the basis of a proposed classification of their main clinical features. The structures supposed to be ictally disorganized are, for each category, as follows: simple and complex visual and auditory hallucinations and illusions are due to a discharge beginning in the temporal-occipital or superior (posterior or anterior) temporal cortex. Memory troubles like dreamy-state are due to a simultaneous impairment of some neo-cortical areas and of Ammon's horn. Instinctive-affective troubles, like genital and sexual signs, or symptoms, emotional, mood, affective troubles seem to be linked to discharges in hippocampal and juxta-insular, internal perisylvian areas. Autonomous (cardiac, digestive, etc.) troubles are linked to a disorganization of basal limbic structures and especially of the perisylvian cortex. Motor and verbal automatisms have different meanings: only chewing is due to a discharge in the amygdalian area and in its hypothalamic efferents. Cognitive impairment is difficult to classify.(ABSTRACT TRUNCATED AT 250 WORDS)

[Contribution to anatomical and clinical studies of avoidance phenomena (author's transl)]. / Contribution à l'étude anatomo-clinique des phénomenes d'évitement.

The authors report 5 cases of avoiding phenomenon of the hand from parietal lesions. Four of these patients were operated for intractable epilepsy, from a parietal cortectomy that implicated a certain amount of white matter. The avoiding phenomena observed are analyzed as elementary motor perturbations rather than a disturbance of motor comportment. The authors distinguish two types of avoiding phenomena: 1--Avoiding phenomenon of dystonic type occurs during any motor activity and persists during all its development. It is probably related to the removal of the cortex of the post-central gyrus and of the anterior part of the superior parietal lobule; 2--The initial avoiding phenomenon is brief and occurs only at the beginning of the movements which implicate solely the upper limb; it seems related to the removal of the internal part of the superior parietal lobule that corresponds approximately to areas 5 and 7 from Brodmann. Some hypotheses are discussed concerning the possible physio-pathological mechanisms of these disturbances.

[Neurophysiopathological hypothesis on startle epilepsy in man]. / Hypothèses neuro-physiopathologiques sur l'épilepsie-sursaut chez l'homme

Clinical observation and S.E.E.G. recordings performed with a surgical purpose in a typical case of startle-epilepsy has led to a reassessment of the relationship of this form of epilepsy and "Startle reaction". It is confirmed that the critical discharges take origin in the primary motor cortex. The authors discuss, in the light of experimental data already published, the physiopathological hypotheses likely to lead to a better understanding of startle epilepsy. On the one hand it is suggested that the startle reaction may be responsible through a feed-back mechanism for triggering the epileptogenic focus. On the other hand it is assumed that afferent pathways, central organization and efferent systems involved in startle reaction and actual fits are different.

[Continuous partial epilepsy: syndrome and disease]. / L'épilepsie partielle continue: syndrome et maladie.

Twenty three patients are described with a Kojewnikow syndrome in order to identify possible etiological factors. According to their history, clinical and E.E.G. features, patients could be classified into two groups; 1) Eleven patients corresponded to the classical description of the Kojewnikow syndrome: variable age at onset of the disease, rare somatomotor seizures, delay of onset of myoclonic jerks often of long duration, myoclonus limited to a small region, normal neurological examination, stable hemiplegia, normal results of psychometric tests, localised E.E.G. alterations. In most of these patients the etiology of the disorder was known, and the symptoms could be related to a localised lesion of the central cortex; 2) the second group (11 patients) presented with completely different characteristics: early onset of fits (age: 2 to 10 years), presence of other seizure types, short delay of onset of myoclonic jerks, high frequency of seizures, localization of myoclonus over large parts of the body, progressive evolution of a motor syndrome, associated neurological signs and disorders of sleep and behavior, progressive mental deterioration, characteristic E.E.G. pattern with long subclinical paroxysms of slow spikes (sharp waves) with variable localization, diffuse cerebral lesions of unknown etiology were found. Only one patient could not be allocated to either group. Several circumstantial data suggest that patients of the second group may suffer from a slow virus infection. Should this hypothesis be confirmed, a reconsideration of the Kojewnikow syndrome from the etiological standpoint would be of great theoretical and practical interest.

[The "epileptogenic zone" in humans: representation of intercritical events by spatio-temporal maps]. / La "zone épileptogène" chez l'homme: représentation des événements intercritiques par cartes spatio-temporelles.

In the preoperative investigation of partial epilepsies, electrical characteristics of the so-called epileptogenic area are of critical interest to localize this area. We have always emphasized that the analysis of ictal events themselves, is more valuable than that of inter-ictal anomalis. One reason for this emphasis has been the absence of a reliable method to evaluate the relationship between the topography of ictal and interictal events. An technique for imaging an intracerebral potential field is reported. It allows to analyse the spatio-temporal distribution of interictal events recorded during the SEEG exploration. This technique applied to an illustrative patient shows that the temporo-spatial distribution of interictal spikes is related to that of the ictal discharge itself. A new hypothesis concerning the build up of an epileptogenic area in man is presented.

[Early right posterior cerebral hemispheric lesion and right speech dominance in 2 right-handed female patients]. / Lésion hémisphérique cérébrale postérieure droite précoce et dominance droite pour le langage chez deux droitières.

Two female patients presented a severe partial epilepsy of early onset and an extended right posterior hemispheric lesion of prenatal or perinatal origin. They were right-handed and all their first degree relatives were right-handed. Nevertheless, evidence of right hemispheric speech was documented in both patients, on the basis of a bilateral sodium amytal test in one case, and of a persistent aphasia after neurosurgical treatment in the other. The possible consequences of an early cerebral pathology on cerebral lateralization are discussed, including pathological right-handedness.

[Behavioral manifestations induced by electric stimulation of the anterior cingulate gyrus in man]. / Manifestations comportementales induites par la stimulation électrique du gyrus cingulaire antérieur chez l'homme

The electrical stimulation of a restricted part of area 24 in awake man elicits important behavioral changes. The present study is dealing with 83 epileptic patients whose brain activity was recorded in SEEG conditions, with a view to possible neurosurgery. In order to determine how seizures originate and propagate, 116 multileads electrodes (65 right, 51 left) were stereotaxically inserted in the anterior part of the cingular gyrus. 521 stimulations were performed. In 362 cases, this stimulation induced a particular behaviour which was characterized by an arousal, motor activities (involving fingers and hand, mouth, legs, eyes, associated movements of hand mouth, highly integrated movements), thymic modifications and hallucinatory manifestations. Topographical organization of the effective area in the cingular gyrus and the relation between the electrical responses and stimulation parameters are studied.

[Auditory response at the posterior part of the first temporal convolution (author's transl)].

Among the epileptic patients investigated by the stereotactic E. E. G. (Talairach) whose electrodes were introduced at or around the auditory cortex (Area 41, 42), the topography of the auditory responses by the electrical bipolar stimulation and that of the auditory evoked potential by the bilateral click sound stimulation were studied in relation to the ac--pc line (Talairach). The positive points of auditory responses and those of evoked potential were found in the posterior part of the first temporal convolution at or around the Hesch's transverse gyrus. The contralateral auditory responses to the stimulating electrodes situated more anterior and superior than the homolateral responses in lateral projection and more medial in frontal projection. The points of the sensation of "elevation" or "fall" elicited by the electrical stimulation which were thought to be related to the vestibular function were scattered more superior and posterior than the points of the auditory responses in lateral projection and more medial in frontal projection. This study gave the accurate topography concerning the auditory responses, the positive auditory evoked potentials and the vestibular function related sensation (sensation of "elevation" or "fall"). Further study will be required to elucidate the functional anatomy of the human auditory cortex.