Transient global amnesia caused by painless aortic dissection

Neurological syndromes secondary to acute aortic dissection (AAD) are uncommon and usually consist of focal deficits after an embolic cerebral infarction. This article reports the observation of an AAD with the chief complaint of transient acute memory impairment-that is, a non-usual stroke-like symptom.

Comorbidité psychiatrique au cours des événements non épileptiques : étude rétrospective dans un centre de vidéo-EEG

INTRODUCTION

Pseudoseizures involve a group of paroxysmal behavioral symptoms mimicking an epileptic seizure, but without modifications of cerebral electrical activity.

PATIENTS AND METHOD

In this retrospective study focusing on mental disorders, 37 patients with pseudoseizures were recorded during video-EEG procedure.

RESULTS

According to DSM-IV criteria, 70 percent of the patients had at least one mental disorder when evaluated. Diagnoses were, in decreasing order of frequency: post-traumatic stress disorders, other anxious disorders, somatoform disorders, dissociative disorders, and mood disorders.

CONCLUSION

The strong association between pseudoseizures and post-traumatic stress disorders is discussed. Our results argue in favor of a systematic evaluation of psychiatric comorbidity.

[Cyclosporin-induced toxic neuromyopathy]

INTRODUCTION

Cyclosporine is an immunosuppressive treatment whose side effects limit its usefulness. Among neurological side effects, neuropathies or myopathies have been reported, specially inpatients given combinations of cyclosporine with co-enzyme A reductase inhibitors.

CASE REPORT

We report here the case of a 67-year-old woman who developed few months after a kidney graft sensorimotor disorders which progressed rapidly. Since all etiologies of such a disorder were ruled out, the hypothesis of toxicity exclusively induced by cyclosporine was suggested and confirmed by the improvement observed after its withdrawal.

CONCLUSION

This observation highlights the fact that cyclosporine may induce neuromyopathies even when given alone at the therapeutic dosage.

Adult onset ornithine transcarbamylase deficiency: an unusual cause of semantic disorders

Ornithine transcarbamylase deficiency (OTCD) is the most common urea cycle disorder. This condition usually presents in neonates or children. This report describes the clinical case of a 21 year old woman who was diagnosed in adulthood during the course of an unexplained coma. After recovery from the coma, she presented very unusual neuropsychological disorders involving memory and the meaning of certain words, suggesting a semantic deficit. The discovery of OTCD in adulthood is rare and the neuropsychological consequences may be unique.

Neuropathie démyélinisante et syndrome de Gougerot-Sjögren : un piège diagnostique

INTRODUCTION

Neuropathies induced by Sjögren's syndrome (SS) are usually axonal. Nevertheless some demyelinating neuropathies have been described in patients with SS. To date, the relationship between demyelinating neuropathies and SS remains imprecise.

CASE REPORT

A 75 year-old man presented with a chronic history of sensory disturbances linked to demyelinating neuropathy. Electroneuromyography revealed a demyelinating neuropathy and complementary tests revealed both Sjögren's syndrome (SS) and HMSN IA.

CONCLUSION

We suggested that an inherited affection might be researched before considering that demyelinating neuropathy might be a form of peripheral nervous system involvement in SS.

Dissections simultanées des deux artères carotides internes et des deux artères vertébrales révélatrices d’un Syndrome d’Ehlers-Danlos type IV

INTRODUCTION

Dissection of cervical arteries is a frequent cause of stroke in young subjects.

CASE REPORT

We report the case of a 34-year-old patient who experienced simultaneous dissection of both internal carotid arteries and both vertebral arteries leading to repeated motor deficit of the right half-body associated with persistent otalgia. Search for an etiology led to the diagnosis of Ehlers-Danlos syndrome type IV.

CONCLUSION

Search for the cause of cervical artery dissection must consider connective tIssue disease, particularly vascular forms of Ehler-Danlos syndrome. Diagnostic, therapeutic as well as prognostic aspects are discussed.

[Functional brain lateralization in children: developmental theories and implication for developmental diseases]

The functional specialization of each hemisphere in adults is now well accepted. Neuropsychology of hemispheric functioning in young children is a more debatable issue and must take into account additional factors such as development and maturation, characterized by complex changes in anatomy and organization. The first part of this review describes the theory behind the development of the functional organization of the brain. Second, we discuss data regarding brain lesions in children with brain damage and with normal development. We comment on the concept of plasticity and the critical period. We also discuss the neurobiological processes underlying the functional organization of the brain in the model of developmental disorders in children. We chose three disorders involving the left hemisphere (developmental dysphasia), both hemispheres (benign rolandic epilepsy) or the right hemisphere (congenital hydrocephalus) in order to examine their relationship to a specific hemispheric functional organization. We used classic neuropsychological tests such as the dichotic listening task, the dichaptic palpation and the time-sharing paradigm. The patterns observed in each pathology are discussed in light of data obtained in children with brain lesions.

[Acute motor axonal neuropathy, enterovirus and Amyotrophic lateral sclerosis: can there be a link?]

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder of both upper and lower motor neurons. Acute motor axonal neuropathy (AMAN) affects only the lower motor neuron and occurs, in the majority of cases, after an infection. To date, the etiology of ALS remains unknown but seems multifactorial. A 60 year-old man with a past medical history of AMAN developed ALS 9 years later. At that time, genomic sequences of enterovirus (echovirus 6 and 7) were detected in cerebrospinal fluid by RT-PCR. This particular succession led to discuss a possible link between theses two disorders and consequently the involvement of enterovirus in the development of ALS.

SMN1 gene study in three families in which ALS and spinal muscular atrophy co-exist

Spinal muscular atrophy (SMA) is caused by SMN1 gene deletions or mutations, and ALS is the most frequent motor neuron condition in adults. The authors describe three families in which ALS and SMA coexist. The authors found that no SOD1 mutation was found within these families; all three ALS cases had at least two SMN1 copies; and an abnormal SMN1 gene locus did not explain the co-occurrence of these two motor neuron disorders in these families.

[Hemimegalencephaly: a misleading EEG tracing]

Hemimegalencephaly is a rare cerebral malformation that usually presents with mental retardation, controlateral hemiparesis and intractable seizures. We report a case of hemimegalencephaly diagnosed in adulthood based on MRI findings. The electroencephalogram initially suggested partial status epilepticus. The diagnosis of this cerebral malformation has been made easier thanks to recent progress in cerebral imagery with MRI. We describe and discuss the relevant encephalographic aspects.

MRI morphometric study and correlation with cognitive functions in young adults shunted for congenital hydrocephalus related to spina bifida

We studied the morphometric MRI findings and their correlation with cognitive functions in a population of 10 young adults shunted for congenital hydrocephalus related to spina bifida. Morphometric MRI analysis included measurement of the ventricular dilatation index, frontal and occipital parenchymal thickness and the size of the corpus callosum. The neuropsychological status was evaluated, notably to look for a discrepancy between verbal and performance skills, a finding which has previously been described in hydrocephalic children. We also investigated whether there was a correlation between cognitive function and cerebral morphometric indexes. In each case, MRI demonstrated the structural changes associated with the Chiari II malformation. The size of the lateral ventricles varied, ranging from important dilatation to small ventricles. Six patients had only partial development of the corpus callosum. All patients had a normal global IQ. In our population of young adults, we did not observe any discrepancy between verbal and visuospatial performances as has been described in children with hydrocephalus. We found no relationship between cognitive function and ventricle dilatation or parenchymal thickness or between the size of the corpus callosum and callosal transfer.

Cognitive function in adolescents and young adults in complete remission from benign childhood epilepsy with centro-temporal spikes

Benign childhood epilepsy with centrotemporal spikes (BECTS) is a frequent, benign childhood epilepsy with a good prognosis. However, neuropsychological deficits have been reported during its active phase. In this study, we evaluate the long-term neuropsychological consequences of this reputedly benign epilepsy, particularly the relation between paroxysmal abnormalities and cerebral language lateralization. The neuropsychological outcomes concerning both overall cognitive and lateral hemispheric functions were studied in twenty-three adolescents and young adults in total recovery from BECTS, in thirty-three controls without any significant past neurological history and in ten adolescents and young adults with complete resolution of generalized idiopathic epilepsy (childhood absence epilepsy or CAE). Language lateralization was evaluated using classical neuropsychological procedures (dichotic listening tasks, dual-task procedure). No difference was seen in the three populations with respect to overall cognitive function: memory, language and the executive functions. Although the Performance IQ was lower in patients in remission from CAE, the results were within normal limits. However, qualitative analysis of the dual-task procedure suggested a different organizational pattern for cerebral language in adolescents and young adults in remission from BECTS as compared to controls and patients in remission from CAE. The different organization in cerebral pattern in BECTS patients appeared to be related to the initial epileptic focus as determined by the EEG and/or the sleep-recording. We discuss the relationship between the presence of paroxysmal anomalies in childhood and subtle functional lateralized hemispheric abnormalities in adulthood.

Sleep and brain lesions: a critical review of the literature and additional new cases

We present a comprehensive review of sleep studies performed in patients with brain lesions complemented by 16 additional personal selected cases and by discussion of the corresponding animal data. The reader is cautioned about the risk of establishing an erroneous correlation between abnormal sleep and a given disorder due to the important inter and intra variability of sleep parameters among individuals. Salient points are stressed: the high frequency of post-stroke sleep breathing disorders is becoming increasingly recognised and may, in the near future, change the way this condition is managed. Meso-diencephalic bilateral infarcts induce a variable degree of damage to both waking and non-REM sleep networks producing and abnormal waking and sometimes a stage 1 hypersomnia reduced by modafinil or bromocriptine, which can be considered as a syndrome of cathecholaminergic deficiency. Central pontine lesions induce REM and non-REM sleep insomnia with bilateral lateral gaze paralysis. Bulbar stroke leads to frequent sleep breathing disorders. Polysomnography can help define the extent of involvement of various degenerative diseases. Fragmented sleep in Parkinson's disease may be preceded by REM sleep behavioural disorders. Multiple system atrophies are characterised by important sleep disorganization. Sleep waking disorganization and a specific ocular REM pattern are often seen in supra-nuclear ophtalmoplegia. In Alzheimer patients, sleep perturbations parallel the mental deterioration and are possibly related to cholinergic deficiency. Fronto-temporal dementia may be associated with an important decrease in REM sleep. Few narcoleptic syndromes are reported to be associated with a tumour of the third ventricle or a multiple sclerosis or to follow a brain trauma; all these cases raise the question whether this is a simple coincidence, a revelation of a latent narcolepsy or, as in non-DR16/DQ5 patients, a genuine symptomatic narcolepsy. Trypanosomiasis and the abnormal prion protein precociously after sleep patterns. Polysomnography is a precious tool for evaluating brain function provided it is realised under optimal conditions in stable patients and interpreted with caution. Several unpublished cases are presented: one case of pseudohypersomnia due to a bilateral thalamic infarct and corrected by modafinil, four probable late-onset autosomal recessive cerebellar ataxias without sleep pattern anomalies, six cases of fronto-temporal dementia with strong reduction in total sleep time and REMS percentage on the first polysomnographic night, one case of periodic hypersomnia associated with a Rathke's cleft cyst and four cases of suspected symptomatic narcolepsy with a DR16-DQ5 haplotype, three of which were post-traumatic without MRI anomalies, and one associated with multiple sclerosis exhibiting pontine hyper signals on MRI.

Quantitative analysis of striatal dopamine D2 receptors with 123 I-iodolisuride SPECT in degenerative extrapyramidal diseases

123I-Iodolisuride has high specific affinity for binding on dopamine D2 receptors in the striatum and has been used in a few single photon emission computed tomography (SPECT) studies of extrapyramidal disorders. The diagnosis of Parkinson's disease (PD) is very difficult in the first 5 years of evolution, with 15-25% false positive diagnoses. The aim of this study was therefore to determine the value of iodolisuride SPECT in discriminating Parkinson's from the most frequent Parkinson-plus syndromes (PPS). Seventeen patients with an extrapyramidal syndrome had a SPECT examination 1 h after injection of 180-185 MBq of 123I-iodolisuride. They were followed under dopaminergic treatment for at least 2 years. After 2 years, they were separated in two groups according to specific clinical criteria and sensitivity to dopaminergic treatment: nine patients had PD (age = 59.8+/-8.8 years; Hoehn and Yahr = 1.8+/-0.7; evolution = 4.3+/-3 years) and eight had PPS (age = 71.6+/-7.3 years; Hoehn and Yahr = 2.9+/-2.0; evolution = 4.1+/-1.5 years). The binding potential of iodolisuride in the striatum was assessed by considering the striatum (S)/occipital lobe (O) ratio at the pseudo-equilibrium 1 h after injection. The S/O ratio was statistically different between PD and PPS (1.97+/-0.3 vs. 1.65+/-0.2 (P<0.02)). Iodolisuride SPECT could differentiate both groups with a sensitivity of 88.8% and a specificity of 75%. Iodolisuride is a good specific D2 receptor ligand for SPECT and complements specific clinical criteria for the diagnosis of Parkinson's disease and differentiation between different extrapyramidal disorders.

[Primary hypereosinophilia syndrome manifesting as encephalopathy and vision disorders]

We report the case of a 60-year-old man who developed visual and cognitive disorders. Investigations confirmed the diagnosis of idiopathic hypereosinophilic syndrome even though the patient had a history of rectal cancer. The olinical course was favorable after treatment. We discuss the different clinical forms, imaging data and treatments of eosinphilic syndrome.

[Primary lateral sclerosis with breast cancer, a potential paraneoplastic neurological syndrome]

Few reports indicate that motor neuron diseases may have paraneoplastic origin. A 70 year-old woman suffering from progressive upper motor neuron disease is presented. Laboratory, radiological and neurophysiologic studies were compatible with primary lateral sclerosis. Six years later a routine screening led to the discovery of a breast cancer, suggesting that the upper motor neuron syndrome could be paraneoplastic. So, in female patients with primary lateral sclerosis, a mammography should be recommended to search for breast cancer.

Continuous spikes and waves during slow sleep (CSWS): outcome in adulthood

We report a longitudinal, electroencephalographic and neuropsychological analysis of epilepsy with continuous spikes and waves during slow sleep (CSWS) in a 19 year-old boy. The clinical course fluctuated, with temporary worsening or improvement of the paroxysmal abnormalities, epilepsy and cognitive functions. At the end of the follow-up period, seizures persisted. Evaluation of the boy's behaviour, language and cognitive function suggested a dysexecutive syndrome. We discuss the relationship between paroxysmal abnormalities and neuropsychological disorders.

[Determination of language dominance using EEG spectral analysis versus the Wada test in temporal epilepsy (right-handed subjects)]

Spectral analysis of the EEG alpha rhythm was studied in nine temporal epileptic right-handed patients in order to predict localization of the speech area. We studied the variation of the spectral power of the alpha rhythm during an activation paradigm previously validated in normal right-handed subjects. Significant alpha power decreases in the left hemisphere during writing with the right hand (as compared to resting) and/or significant alpha power decreases in the right hemisphere during left-hand recognition and classification of cardboard objects (as compared to resting) were considered as consistent with left-hemisphere dominance for language. The results of EEG spectral analysis were compared with those of the Wada test. The left hemisphere was dominant for language according to the Wada test in eight subjects and the right hemisphere in one subject. Six patients had a significant alpha power reduction in the hemisphere concerned during lateralized cognitive tasks, consistent with language localization in the left hemisphere according to the Wada test. The three remaining patients had no significant EEG spectral power variations. A significant decrease of alpha power in the active hemisphere during cerebral activation seems statistically related to left-hemispheric dominance for language in right-handed subjects (hemispheric specialization). However, the localization of the speech area using this electrophysiological method does not appear clinically relevant for a case-by-case decision in individual patients.

Sleep and epilepsy

This review considers the effect of sleep on seizures and interictal electroencephalogram (EEG) paroxysmal activities (PAs), as classified by the International League Against Epilepsy criteria. No type of seizure is, per se, specifically linked with non-rapid eye movement (NREM) or rapid eye movement (REM) sleep. However, in some syndromes, seizures are more frequent in slow wave sleep (SWS) [partial motor or generalized seizure in benign epilepsy with centro-temporal spikes (BECTS), frontal seizures in idiopathic familial or not familial frontal lobe epilepsy and generalized tonic seizure in secondary generalized epilepsy are increased by SWS]. Conversely myoclonia and grand mal seizures are associated with awakening in some forms of generalized idiopathic epilepsy. There is a mean increase in PAs during SWS in generalized and in partial epilepsies on the whole. However, precise analysis shows that in partial cryptogenic or symptomatic epilepsy and, most likely, in the majority of generalized idiopathic epileptic syndromes about 20% of patients have an increase in PA density during SWS, 20% experience an increase in waking, 50% have very few PAs and in 10% there is no significant difference between sleep and waking. BECTS, however, exhibits a definite increase in sleep PA increase and in juvenile myoclonic epilepsy an increase in PAs during the intra-night awakening is reported. There are at least three syndromes, which cause a huge increase in PAs during sleep: the Landau-Kleffner syndrome and the syndromes of continuous focal or generalized spike-waves during SWS. Their physiopathology and neuropsychological consequences are discussed. Neurophysiological animal data are also reported highlighting the relationships between slow sleep oscillations and the generation of spike waves. A biochemical review is also presented.