[The timing of crisis and day-night distribution of paroxysmal EEG activities: a study on 197 epileptic patients]. / Horaires des crises et répartition nycthémérale des activités EEG paroxystiques: étude chez 197 épileptiques.

The purpose of the present study was to determine whether paroxysmal EEG activity (PA) occurs randomly over time and whether seizures arise at time of maximum PA. 204 ambulatory recordings (A/EEG) in 197 adult epileptic outpatients have been were included. The patients' seizures were grouped according to ILAE classification: Simple partial seizures; complex partial seizures (CPS), isolated or secondarily generalized; idiopathic generalized seizures: epilepsy with myoclonic absences, generalized tonic-clonic seizures (GTCS) on awakening, GTCS with photo-sensitivity; undetermined epilepsies: "grand mal morpheique", epilepsies with generalized PA without photosensitivity or with All recordings were performed with a 8-channel 24 h cassette recorder system (Medilog 9,000). The video play-back speed used was 20 times the recording speed to allow good detection, characterization and localization of PA. Counting was accomplished by visual analysis. No PA during A/EEG was noted in 24.5 p. 100 of all cases. A diurnal distribution in wakefulness was found in 59 p. 100 of idiopathic generalized epilepsies, PA usually occurring on awakening whatever the specific time of day; in 27 p. 100 of CPS and 20 p. 100 of undetermined epilepsies, with peak PA occurrence at late morning and 6 pm. During resting-state and afternoon-naps, PA occurrence was mainly seen in CPS. PA occurring only in overnight sleep was observed in 17 p. 100 of CPS and 20 p. 100 of undetermined epilepsies. PA distribution pattern in both CPS and undetermined epilepsies suggests an ultradian rhythm (time-dependent). On the other hand, PA pattern in idiopathic generalized epilepsies support the hypothesis of a circadian rhythm linked to sleep/wake--or light/dark--cycle (state-dependent).

[Psychiatric presentation of human African trypanosomiasis: overview of diagnostic pitfalls, interest of difluoromethylornithine treatment and contribution of magnetic resonance imaging]. / Forme psychiatrique de trypanosomiase africaine: illustration des difficultés diagnostiques et apport de l'imagerie par résonance magnétique.

We report a case of a western African man, residing in France for 4 years, who developed human African trypanosomiasis (HAT) caused by Trypanosoma brucei gambiense. Diagnosis was made at a late stage of the disease. The disease was misdiagnosed and untreated for several years because the clinical presentation was limited to psychiatric disorders and biological confirmation was difficult. Polysomnographic recordings demonstrated typical alterations of HAT. Difluoromethylornithine was effective in this late stage of the disease. Magnetic resonance imaging showed brain edema with demyelination and associated brain atrophy and abnormal signals in the brainstem and thalamus, both implied in sleep-wake cycle.

[Sub-cortico-frontal encephalopathy and choreic movements related to recombinant interferon-alpha 2b]. / Encéphalopathie sous-cortico-frontale et mouvements choréiques liés à l'interféron-alpha 2b recombinant.

Interferon (IFN)-alpha is associated with central nervous system (CNS) side effects such as depression and suicide ideation, somnolence, confusion, drowsiness, psychomotor slowing, memory impairment and visual disorientation. More severe complications are uncommon and include frank paranoia, dementia, coma, seizures and neuropathy. With the increasing long-term and extensive use of interferon (IFN)-alpha several new neurologic adverse effects have been recognized. We report on two patients who developed severe subcortico-frontal impairment, associated in one case with choreic movements, after a long-term treatment with IFN-alpha 2b for hematologic malignancies. Our patients rapidly and completely recovered from their cognitive and motor symptoms after the discontinuation of the drug. The same neurologic symptoms reappeared when we attempted to reintroduce lower doses of IFN-alpha in one case. Although little is known regarding IFN-alpha actions in the CNS, several possible mechanisms may underlie its neurotoxicity and might result from complex direct and indirect effects involving brain vasculature, neuroendocrine system, neurotoxic secondary cytokines'release and neurotransmitters.

[Echotomography of the carotid bifurcation (author's transl)]. / Examen de la bifurcation carotidienne par échotomographie.

Echotomography examinations of carotid bifurcation were conducted in 19 patients, with a real-time apparatus (71 crystals, 7 MHz). Serial transversal sections plus two or more longitudinal sections enabled identification by Echo-B of the three carotid arteries, and thus the bifurcation, in 37 instances. Arteriography was performed in 11 patients (21 carotid arteries). Correlation between Echo-B and arteriographic findings was good in 10 cases (including 1 case of occlusion and 2 of stenosis). There were 3 false negatives but no false positives. Echo-B did not detect the bifurcation on either side in one patient. The method is non-invasive, painless, and can be repeated without risk. It enables the detection of stenotic and occlusive lesions with a certain degree of reliability. It is also of value for demonstrating the presence of atheromatous plaques, and to some extent, irregularities in the arterial wall or variations of its diameter. It allows new perspectives for long-term following of patients after medical or surgical treatment.

[Measurement of carotid diastolic flow by ultrasonography using the Doppler effect, and its value in diagnosis (authors transl)]. / Le flux diastolique carotidien en ultrasonographie par effet Doppler moyens d'étude et valeur sémiologique.

Blood supply to the brain is related to carotid diastolic flow, which is a function of cardiac output and distal arterial resistance. It is used to calculate the resistance index (Ir) of Planiol and Pourcelot which enables quantitative measurement of distal circulatory resistance. The Ir is of no value in young subjects with satisfactory arterial compliance and in atheromatous subjects with flattened curves from loss of elasticity of the arterial walls. More precise information can be obtained by calculating the ratio of the areas under the curves. Diastolic flow may be reduced (Ir tending towards 1) or increased (Ir lower than normal) either uni- or bilaterally, with very different diagnostic significance. Unilateral flow reduction results from partial obstruction while bilateral reduction occurs during the course of general affections. Angiomas cause a unilateral increase in flow. Variations in the results of repeated examinations can also supply useful information.

[The transcranial Doppler in the adult. Preliminary results in 31 patients]. / Le Doppler transcrânien chez l'adulte. Résultats préliminaires chez 31 patients.

Non-invasive transcranial Doppler US investigation in adult patients was first described by Aaslid et al. (1982). The apparatus consists in a 2 MHz bidirectional pulsed Doppler with spectrum analyser. Middle and anterior cerebral arteries were insonated by transtemporal exploration, basilar artery by occipital foramen. The criteria of identification were: position and angulation of the probe, direction of the flow, depth of sample volume. The authors present a first series of 31 patients, all with cervical CW Doppler and B-mode Echo. The percentage of identification was: MCA 72%; ACA 69%; BA 54%. Some clinical cases are illustrated. The interest of the method is emphasized in spite of constraints depending on probe position and anatomical variability of the circle of Willis: ambulatory and non-invasive methods; assessment of intracranial blood flow in various conditions: cerebral ischemia and infarction, intracerebral angioma; complementarity with other non-invasive and non-expensive techniques: EEG and cervical US investigation.

[Value of cassette-recorded long-term 8-channel EEG monitoring--ambulatory recording in known epileptics]. / Intérêt de l'EEG de longue durée sur cassette avec 8 dérivations--enregistrement ambulatoire chez des épileptiques connus.

The authors insist on the real improvement of ambulatory EEG recording due to the new 8-channel cassette recorder (Medilog 9000*). They emphasized: (1) its maniability with full independence of patients and physiological sleep recordings at home; (2) its viability, the same as conventional EEG with 8-channel montages; (3) its performant video-screen replay system, with easy paper transcription. The results in 50 ambulatory epileptic patients out of the 100 examinations actually realized in the EEG laboratory with this new device are detailed. Most interesting, in addition to sleep recording, is recognizing the number and the time repartition of paroxysmal discharges every 24 h; increasing the chances of recording randomly occurring seizures and the future chronobiological studies. The indications in epileptic seizures are myoclonic and 'temporal' epilepsies and also, with one channel for ECG recording, the diagnosis of attack of uncertain etiology.

[Value of cassette-recorded long-term 8-channel EEG monitoring in status epilepticus--technical note]. / Interêt de l'EEG de longue durée enregistré sur cassette avec 8 dérivations dans les états de mal épileptiques--note technique.

Prolonged EEG-taped recording is a significant recent improvement in technique, with the 8 channels providing the possibility of exploration of the whole scalp. First used for ambulatory monitoring, it was also tested in comatose patients with status epilepticus. The advantages are: the the good quality of the EEGs even after recording continuously for many days, and without drawback for intensive nursing; the help in recognizing infraclinical seizures, often misunderstood by the nursing staff, and the control of treatment; the participation in prospective chronobiological studies.

As well as physiological states, pathological states and therapeutical problems may be a gushing spring for biological theory--and conversely.

New class of therapies, including bipolar therapies (BPT) and "paradoxical" unipolar therapies (PUT) were firstly proposed in relation to a clinical insight and to some results of biological investigations, then they gave rise to mathematical modeling which brought a justification of these therapies, at least from a theoretical point of view. After recalling the mathematical model for the regulation of agonistic antagonistic couples, and reporting the fundamental types of control simulation by means of it, we point out the validity of therapeutical applications inferred from this model. These therapy modalities, including BPT and PUT, now concern the following diseases: astrocytomas, epilepsia and trials on multiple sclerosis. Even if such attempts are in their early stage, noticeably for the last case where biological changes have mainly been studied, it seems that a large span of treatments is open to BPT and PUT. Improvement of these techniques in the future depends, in our opinion, on a parallel working on the dynamics of the mathematical model and the dynamics, perceived by clinical insight and confirmed by biological investigations, of the body reactions to such strategies. Justification of BPT and PUT was given, by resorting to the notion of "pathological homeostasis" which, too often, intervenes in order to nullify the effects of unilateral (not paradoxical) therapies. This research has elicited some therapies which use two agents with antagonistic effects or only an agent with effects similar to the agent already in excess in the body--in both cases at nearly physiological doses.

Cyclic alternating pattern as a provocative factor in nocturnal paroxysmal dystonia.

PURPOSE: We made a polygraphic study of 6 patients with nocturnal paroxysmal dystonia (NPD) in which the cyclic alternating pattern (CAP) parameters were compared with those of a group of age- and sex-matched controls. METHODS: All patients met the requirements for NPD diagnosis, characterized by generalized stereotyped movements (dystonic-dyskinetic), with a 1-min centered duration but with no clear evidence of epileptic abnormalities in the waking EEG and during nocturnal recordings. RESULTS: Besides the major events, the NPD polysomnograms also showed shorter, repeated episodes of shorter duration (generally <20 s) consisting of abrupt movements involving one or more body segments. Overall, the motor events in patients with NPD were closely related to periods of unstable non-REM (NREM) sleep, as evidenced by the sequences of CAP, and began during an A phase. According to the conventional scoring parameters, NPD and controls differed only in sleep latency (+14 min in the NPD patients: p < 0.04). However, the architecture of sleep in the group with NPD was characterized by prolonged and irregular NREM/REM cycles. In addition, the NPD recordings showed significantly higher values of CAP rate (p < 0.0001). When major motor attacks were suppressed by medication, sleep was characterized by a decrease in the excessive amounts of CAP rate and by a more regular architecture. CONCLUSIONS: The modulatory role of CAP on nocturnal motor events is reported.