Obstructive sleep apnoea syndrome: comparison between polysomnography and portable sleep monitoring based on jaw recordings.

INTRODUCTION: Obstructive sleep apnoea syndrome (OSAS) constitutes a new major public health problem because of its several pathophysiologic consequences such as cognitive disorders, excessive daytime sleepiness with risks of traffic accidents, cardiovascular implications, and decrease of quality of life. The necessity of a gold-standard polysomnography to ensure an accurate diagnosis implies an expensive, technical and time-consuming examination. Thus, it seems logical to develop new systems so as to diagnose SAS and to make it possible to detect apnoeas/hypopnoeas easily during sleep even at home. AIM OF THE STUDY: To assess a novel type-3 portable monitoring (PM) device, the Somnolter, and dedicated automatic analysis of several signals, one of which is the mandibular movement signal. METHOD: We studied patients suffering from OSAS. For all the patients, a nocturnal diagnosis polysomnography (PSG) was recorded in hospital settings, based on six EEG channels, two EOG channels, chin EMG channel, EKG, and respiratory parameters. At the same time, the Somnolter PM device recorded the physiological parameters from its own nasal prongs, thoracic belt, pulse oxymeter, body position, and jaw movement sensors. A visual analysis of PSG recordings was made leading to the detection of apnoea/hypopnoea index (AHI-PSG) and an automatic analysis of the Somnolter traces was performed to get automatic apnoea/hypopnoea index (AHI-A). The added value of the mandible movement signals was the particular jaw movements related to arousals, to respiratory efforts and to sleep/wake state. A comparison was made between the automatic and gold AHIs standard and the correlation was calculated between them. RESULTS: Ninety patients, aged between 47 and 70 years (mean age: 55.4±8.7) took part in the study. The linear regression and the correlation coefficient between AHI-PSG and AHI-A showed the good reliability of the automatic method. The Bland Altman analysis shows a correlation of 0.95 with a sensitivity of 83.6 and specificity of 81.8. CONCLUSION: The dedicated automatic analysis based on mandibular movements presents a good potential for the diagnosis of OSAS. The AHI computed by the automatic method is correlated with the AHI-PSG and the Somnolter could easily be used both in hospital, and in ambulatory settings.

Creutzfeldt-Jakob disease with slow progression. A mimickry of progressive supranuclear palsy.

Sporadic Creutzfeldt-Jakob disease (sCJD) does not always present with typical clinical signs, such as myoclonus in association with periodic sharp-wave complexes. We present a 67-year old female patient with initial falls and vertical gaze palsy, suggesting the diagnosis of Progressive Supranuclear Palsy (PSP). EEG and MRI were not contributory. Typical clinical and paraclinical CJD signs were only seen after 17 months. The diagnosis was confirmed by autopsy. - CJD can be a neurodegenerative chameleon. The present case adds to the scare literature of slowly evolving CJD mimicking Parkinsonism related to tauopathies.

Exploration of small fibers for testing diabetic neuropathies.

INTRODUCTION: Electrophysiological exploration of neuropathies is a standard method of investigating the dysfunction of myelinated larger fibers (Aalpha, Abeta). However, this method cannot test dysfunctions in other fibers. To evaluate the smaller (Adelta) and unmyelinated fiber (C-fibers) lesions a quantitative method has been perfected: the study of the sensory thresholds (quantitative sensory testing: QST). It allows the investigation of the sensory symptoms and is a reproducible, non-invasive and painless method. It is used above all in patients suffering from diabetic neuropathy ('Diabetes Care 9 (1987) 432'). PATIENTS AND METHODS: We used the QST testing in comparison with nerve conduction velocities in 40 Non-Insulin-Dependent Diabetes Mellitus (NIDDM or Type II) patients in their 60s (+/-10 years). Depending on the duration of their diabetes (dd), we distinguished three groups: dd < 5 years (GI) dd from 5 to 15 years (GII) and dd > 15 years (GIII). All the patients underwent a clinical neurological examination, which enabled us to establish a gravity score comparable to the NDS (Neuropathy Disability Score: 'Muscle Nerve 10 (1988) 21'). RESULTS: Nerve conduction velocities and QST were studied for each group of patients. Electrophysiological alterations were connected to the gravity clinical score and in some asymptomatic patients a higher QST heat threshold could be observed. DISCUSSION: These results indicate that QST can detect the early dysfunction of the unmyelinated fibers in this kind of neuropathy. Subclinical detection can reduce severe neurological complications and make possible an early and effective treatment.

[Indications of electroencephalogram in the newborn]. / Indications de l'électroencéphalogramme en période néonatale. Recommandations du groupe de neurophysiologie clinique de l'enfant.

The electroencephalogram (EEG), an easy-to-use and non invasive cerebral investigation, is a useful tool for diagnosis and early prognosis in newborn babies. In newborn full term babies manifesting abnormal clinical signs, EEG can point focal lesions or specific aetiology. EEG background activity and sleep organization have a high prognostic value. Tracings recorded over long period can detect seizures, with or without clinical manifestations, and differentiate them from paroxysmal non epileptic movements. The EEG should therefore be recorded at the beginning of the first symptoms, and if possible before any seizure treatment. When used as a neonatal prognostic tool, EEG background activity is classified as normal, abnormal (type A and type B discontinuous and hyperactive rapid tracing) or highly abnormal (inactive, paroxysmal, low voltage plus theta tracing). In such cases, the initial recording must be made between 12 and 48 h after birth, and then between 4 and 8 days of life. Severe EEG abnormalities before 12 h of life have no reliable prognostic value but may help in the choice of early neuroprotective treatment of acute cerebral hypoxia-ischemia. During presumed hypoxic-ischemic encephalopathy, unusual EEG patterns may indicate another diagnosis. In premature newborn babies (29-32 w GA) with neurological abnormalities, EEG use is the same as in term newborns. Without any neurological abnormal sign, EEG requirements depend on GA and the mother's or child's risk factors. Before 28 w GA, when looking for positive rolandic sharp waves (PRSW), EEG records are to be acquired systematically at D2-D3, D7-D8, 31-32 and 36 w GA. It is well known that numerous and persistent PRSW are related to periventricular leukomalacia (PVL) and indicate a bad prognosis. In babies born after 32 GA with clinically severe symptoms, an EEG should be performed before D7. Background activity, organization and maturation of the tracing are valuable diagnosis and prognosis indicators. These recommendations are designed (1) to get a maximum of precise informations from a limited number of tracings and (2) to standardize practices and thus facilitate comparisons and multicenter studies.

[Electroclinical characteristics of seizures in the Aicardi syndrome]. / Charctères électrocliniques des crises dans le syndrome d'Aicardi.

Electro-clinical patterns of seizures were studied in 7 infants with Aicardi Syndrome. In all 7 cases, partial seizure preceded the appearance of asymetrical spasms. Partial seizures and spasms were recorded by polygraphing tracings of long duration. There was a constant correlation between the EEG localization of partial seizures and the side of asymetrical spasms. In 6 cases, a cluster of spasms followed the partial discharge whereas in the 7th case, the partial discharge appeared in the middle of the cluster. Therefore, both partial seizure and cluster of spasms seem to be part of the same critical manifestation. The authors have recorded the same king of seizures in other malformative syndromes (lissencephaly, Bourneville disease) and compare them to those recorded in Aicardi Syndrome. In Aicardi Syndrome, this type of seizures might be in relation with the association of a corpus callosum agenesy and paraventricular heterotopies.

The electro-encephalogram in the term neonate. Case reports.

The use of a portable electro-encephalographic (EEG) recorder has proved to be a very useful additional investigation in the neonatal intensive care unit. The normal EEG patterns in term infants are easily recognizable. Inactive or burst/suppression (paroxysmal) recordings during the first week of life signify a poor prognosis.

[Unilateral status epilepticus during the neonatal period]. / Les états de mal unilatéraux au cours de la période néonatale.

Twenty-one newborns displaying a strictly unilateral status epilepticus were studied. Three groups have been isolated according to the aetiology: neonatal anoxia (n = 5), postcardiac surgery (n = 8), cerebral hemispheric lesions confirmed by CT scan (n = 7). The authors relate in detail the clinical features and the EEG abnormalities, ictal and interictal in each group, and comment on their results. They show the importance of EEG in establishing or detecting a unilateral status epilepticus and in helping the aetiologic diagnosis.

[Study of fast rhythms and their variations using automatic analysis]. / Approche des rythmes rapides et de leurs variations par l'analyse automatique.

In two dispatching centers, 50 recordings were obtained from 14 workers. The recorded parameters were 2 EEG, 1 ECG, 1 EOG and 1 EMG; the whole day was covered by the various shifts. The results presented here are about the occipito-vertex EEG. After recording, a Fast Fourier Transform was done and the variations of the parameters beta1, beta2 and delta were analysed. Some periodicities are found during the night and the day. The variation of the high frequencies parameters is associated with the working constraints and the internal time-structure of the subject.

[Prognostic value of EEG in pneumococcal meningitis in children]. / Valeur pronostique de l'EEG dans les méningites à pneumocoques chez l'enfant.

We studied the prognostic value of initial EEG in 36 children with a pneumococcal meningitis. The children were divided into 2 groups: infants under 1 year old, and children over 1 year old. The evolution was favourable in 5 cases out of 6 with normal or subnormal initial EEG. The evolution was unfavourable every time we recorded a status epilepticus. When the initial EEG is 'altered' or 'very altered' the prognosis is more difficult to determine but we did not find any sequelae after transitory localised abnormalities with a clinical neurological deficit. The EEG seems to be important for the surveillance and the prognosis of pneumococcal meningitis.

[Electroencephalographic aspects and thiopental in 4 cases of severe pneumococcal meningitis in children]. / Aspects électroencéphalographiques et thiopental dans quatre cas de méningites à pneumocoques graves chez l'enfant.

We present an electroclinical study of 4 severe pneumococcal meningitis cases with intracranial hypertension. In addition to classical anticerebral edema therapy thiopental infusion was used. The plasma thiopental level seems to be only an incomplete indicator of cerebral drug effect, but must be measured to avoid accumulation. EEG monitoring appears to be better in evaluating the clinical status and barbituric impregnation. The burst suppression in EEG recording is noted at variable periods (9-48 h) after the start of the treatment and disappears on discontinuation of infusion while the plasma drug levels remain high. Further, in two cases EEG changes preceded clinical deficits. Evolution of clinical and EEG status was good in the 4 children.

[Neonatal status epilepticus of unknown etiology (author's transl)]. / Etats de mal neonataux d'etiologie indeterminee.

Forty-three neonates with status epilepticus of unidentified etiology were studied by EEG. 90% had favorable outcome. In the cases with unfavorable evolution the following criteria allowed an early poor prognosis: a very early onset of the seizures in the first or second day of life, the presence of tonic seizures and hypertony between seizures, duration of the seizures more than 4 days, EEG activity in the frequency of the alpha band during the seizures, a flat tracing after the seizures, very discontinuous activity between the seizures and, finally, the reappearance of seizures after a seizure-free interval. In the cases of favorable outcome, an EEG follow-up is necessary: in 10% of these cases focal spikes appeared after 2 years without seizures. The necessity of prolonged anti-comital treatment is discussed.

[Unilateral epilepsy with hemiplegia in the child (author's transl)]. / A propos d'une forme d'epilepsie hemiconvulsive avec hemiplegie chez l'enfant.

Fifteen children between the age of 3 and 7 years who had had unilateral seizure followed by a transitory hemiplegia (without fever) were observed. This seizure was the only one in 13 of the children; a second fit appeared in 2 others. The average duration of the observation period was 10 years, 6 months. The evolution of the EEG shows that after a post-ictal delta focus contralateral to the hemiplegia, spike foci of variable localisations were formed in 12 cases. These cases, chosen because of their benign evolution, seem to be related closely to rolandic paroxysmal epilepsy (EPR).

[EEG appearance during waking and falling asleep in children aged 1-4 years (without serious pathology)(author's transl)]. / Aspects EEG de l'endormissement et du réveil chez l'enfant de 1 à 4 ans (pathologie lourde exclue) (author's transl)]

The authors have studied the EEG characteristics of 188 children aged 1-4, without serious pathology, during waking and falling asleep spontaneously in the afternoon. The children were divided into 3 groups: aged 12-23 months, 24-35 months and 36-47 months. On falling asleep the EEG appearances varied, but hypersynchrony was most marked in the youngest children and in the older group theta activity was commonest. Only 3 of the 188 children had runs of paroxysmal activity on falling asleep. The waking study again showed appearances governed by the patients' age with respect to 7 c/sec activity on provoked waking, but the appearances were more diverse on spontaneous waking and anterior theta activity only occurred in the oldest children. In general, a relation appeared to exist between the EEG appearance on falling asleep and on waking, in the respect that children falling asleep without hypersynchrony never wake up with it.

[Prognostic value of the EEG in the days following head injuries in children and adolescents (author's transl)]. / Interet pronostique de l'eeg dans les jours qui suivent certains traumatismes craniens de l'enfant et de l'adolescent.

This study reports on 52 children and adolescents, with head injuries, in whom the EEG, recorded from 24 to 48 h after the accident, showed a focus of monomorphic or regular delta waves. The focus was most often localized in the occipital region, less frequently in the frontal or temporal lobe. In half of the cases, the patients presented a clinical symptomatology which could be alarming. In all of them the evolution was favourable, clinical signs regressing in a few days. A second EEG, recorded 1 week after the trauma, indicated either clear improvement, or complete normalisation. The importance of these data for the management of head injuries in the child, seems unquestionable.