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Anne-marie Elandtblom - One of the best experts on this subject based on the ideXlab platform.

  • Reduced thalamic and pontine connectivity in Kleine-Levin Syndrome
    Frontiers Media S.A., 2014
    Co-Authors: Maria Eengström, Thomas Ekarlsson, Anne-marie Elandtblom
    Abstract:

    The Kleine-Levin Syndrome is a rare sleep disorder, characterized by exceptionally long sleep episodes. The neuropathology of the Syndrome is unknown and treatment is often inadequate. The aim of the study was to improve understanding of the underlying neuropathology, related to cerebral networks, in Kleine-Levin Syndrome during sleep episodes. One patient with Kleine-Levin Syndrome and congenital nystagmus, was investigated by resting state functional Magnetic Resonance Imaging during both asymptomatic and hypersomnic periods. Fourteen healthy subjects were also investigated as control samples. Functional connectivity was assessed from seed regions of interest in the thalamus and the dorsal pons. Thalamic connectivity was normal in the asymptomatic patient whereas the connectivity between the brain stem, including dorsal pons, and the thalamus was diminished during hypersomnia. These results suggest that the patient’s nystagmus and hypersomnia might have their pathological origin in adjacent dorsal pontine regions. This finding provides additional knowledge of the cerebral networks involved in the neuropathology of this disabling disorder. Furthermore, these findings regarding a rare Syndrome have broad implications and results could be of interest to researchers and clinicians in the whole field of sleep medicine

  • SPECT in the Kleine-Levin Syndrome, a possible diagnostic and prognostic aid?
    Frontiers Media S.A., 2014
    Co-Authors: Maria Eengström, Anne-marie Elandtblom, Patrick Emanuel Vigren
    Abstract:

    INTRODUCTION: Kleine-Levin Syndrome (KLS) is a rare Syndrome of periodic hypersomnia and behavioral and cognitive symptoms based on clinical criteria. In the setting of differential diagnosis of hypersomnia disorders, an objective diagnostic aid is desirable. A promising modality is single photon emission computed tomography (SPECT). As intraepisodal investigations are difficult to perform, an interepisodal investigation would be very helpful. Another aim of the study was to correlate SPECT findings to prognosis. METHODS AND MATERIAL: 24 KLS-patients were categorized as severe or non-severe based on clinical characteristics. The clinical characteristics were analyzed in relation to SPECT-examinations performed between hypersomnia periods (interepisodal) or after remission, as a clinical routine investigation.RESULTS: 48% of the KLS-patients have hypoperfusion in the temporal or fronto-temporal regions. In patients that have undergone remission, 56% show that pattern. There were no specific findings related to prognosis.DISCUSSION/CONCLUSION: SPECT might be a diagnostic aid, in a setting of hypersomnia experience. With a sensitivity of 48%, interepisodal SPECT alone cannot be used for diagnosing KLS

  • The sleepy teenager - diagnostic challenges
    Frontiers Media S.A., 2014
    Co-Authors: Anne-marie Elandtblom, Maria Eengström
    Abstract:

    The sleepy teenager is a diagnostic challenge because the problems may be physiological or pathological, with behavioural, social and pychological expressions. It is of great importance that health staff that encounter young people with sleep disturbance have good knowledge about the diseases that must be excluded. Narcolepsy, periodic hypersomnia like Kleine Levin Syndrome, delayed sleep phase Syndrome and obstructive sleep apnoea Syndrome, depression and substance use as well as fatigue from chronic disease like multiple sclerosis should be investigated. Clinical assessment, neurophysiological and laboratory investigations constitute important support in these investigations. Functional methods, for example fMRI, are being developed. The role of computer gaming and use of social media in the night is discussed in relation to these diseases. Cognitive dysfunction may develop with several of the conditions. There is need for increased awareness of how to investigate sleep disturbance in children and young people

  • Brain and effort: brain activation and effort-related working memory in healthy participants and patients with working memory deficits
    Frontiers Media S.A., 2013
    Co-Authors: Maria Eengström, Thomas Ekarlsson, Anne-marie Elandtblom
    Abstract:

    Despite the interest in the neuroimaging of working memory, little is still known about the neurobiology of complex working memory in tasks that require simultaneous manipulation and storage of information. In addition to the central executive network, we assumed that the recently described salience network (involving the anterior insular cortex and the anterior cingulate cortex) might be of particular importance to working memory tasks that require complex, effortful processing. Method: Healthy participants (n=26) and participants suffering from working memory problems related to the Kleine-Levin Syndrome (a specific form of periodic idiopathic hypersomnia; n=18) participated in the study. Participants were further divided into a high and low capacity group, according to performance on a working memory task (listening span). In a functional Magnetic Resonance Imaging (fMRI) study, participants were administered the reading span complex working memory task tapping cognitive effort. Principal findings: The fMRI-derived blood oxygen level dependent (BOLD) signal was modulated by 1) effort in both the central executive and the salience network and 2) capacity in the salience network in that high performers evidenced a weaker BOLD signal than low performers. In the salience network there was a dichotomy between the left and the right hemisphere; the right hemisphere elicited a steeper increase of the BOLD signal as a function of increasing effort. There was also a stronger functional connectivity within the central executive network because of increased task difficulty. Conclusion: The ability to allocate cognitive effort in complex working memory is contingent upon focused resources in the executive and in particular the salience network. Individual capacity during the complex working memory task is related to activity in the salience (but not the executive) network so that high-capacity participants evidence a lower signal and possibly hence a larger dynamic response

Dauvilliers Yves - One of the best experts on this subject based on the ideXlab platform.

  • Narcolepsy and Other Central Hypersomnias
    'Ovid Technologies (Wolters Kluwer Health)', 2017
    Co-Authors: Dauvilliers Yves, Barateau Lucie
    Abstract:

    International audiencePURPOSE OF REVIEW: This article focuses on the clinical presentation, pathophysiology, diagnosis, differential diagnosis, and management of narcolepsy type 1 and narcolepsy type 2, idiopathic hypersomnia, Kleine-Levin Syndrome, and other central disorders of hypersomnolence, as defined in the International Classification of Sleep Disorders, Third Edition (ICSD-3). RECENT FINDINGS: In ICSD-3, the names of some central disorders of hypersomnolence have been changed: narcolepsy with cataplexy and narcolepsy without cataplexy have been renamed narcolepsy type 1 and narcolepsy type 2, respectively. A low level of hypocretin-1/orexin-A in the CSF is now theoretically sufficient to diagnose narcolepsy type 1, as it is a highly specific and sensitive biomarker. Conversely, other central hypersomnias are less well-defined disorders with variability in the phenotype, and few reliable biomarkers have been discovered so far. The epidemiologic observation that influenza A (H1N1) infection and vaccination are potential triggering factors of narcolepsy type 1 (discovered during the 2009 H1N1 pandemic) has increased interest in this rare disease, and progress is being made to better understand the process (highly suspected to be autoimmune) responsible for the destruction of hypocretin neurons. Treatment of narcolepsy remains largely symptomatic, usually initially with modafinil or armodafinil or with higher-potency stimulants such as methylphenidate or amphetamines. Several newer wake-promoting agents and psychostimulants have also been developed, including sodium oxybate, which has a role in the treatment of cataplexy and as an adjunctive wake-promoting agent, and pitolisant, a selective histamine H3 receptor inverse agonist that is currently only available in Europe. SUMMARY: Although far less common than many other sleep disorders, central hypersomnias are among the most severe and disabling diseases in the field of sleep medicine, and their early recognition is of major importance for patients, especially children, to maximize their quality of life and functioning in activities of daily living

  • Consultation initiale, analyse de la plainte et enquête étiologique devant une hypersmnolence
    J B Bailliere et Fils, 2016
    Co-Authors: Evangelista Elisa, Barateau Lucie, Dauvilliers Yves
    Abstract:

    International audienceExcessive sleepiness is a common problem, defined by a complaint of excessive daytime sleepiness almost daily with an inability to stay awake and alert dosing periods at sleep, with episodes of irresistible sleep need or drowsiness or non-intentional sleep, or by a night's sleep time overly extended often associated with sleep inertia. This sleepiness is variable in terms of phenotype and severity to be specified by the out-patient clinic. It is considered to be chronic beyond three months and often responsible for significant functional impairment of school and professional performance, of the accidents and cardiovascular risk. We need to decipher the causes of excessive sleepiness: sleep deprivation, toxic and iatrogenic, psychiatric disorders (including depression), non-psychiatric medical problems (obesity, neurological pathologies...), sleep disorders (as for example the sleep apnea Syndrome), and finally the central hypersomnias namely narcolepsy type 1 and 2, idiopathic hypersomnia, and Kleine-Levin Syndrome. If careful questioning often towards one of these etiologies, need most of the time a paraclinical balance with a sleep recording to confirm the diagnosis. Patients affected with potential central hypersomnia must be referred to the Sleep Study Centers that have the skills and the appropriate means to achieve this balance sheet

  • Preliminary results on CSF biomarkers for hypothalamic dysfunction in Kleine–Levin Syndrome
    'Elsevier BV', 2015
    Co-Authors: Lopez Regis, Barateau Lucie, Chenini Sofiene, Dauvilliers Yves
    Abstract:

    International audienceOBJECTIVE:To measure CSF biomarkers of hypothalamic dysfunction in patients with typical Kleine-Levin Syndrome (KLS) during symptomatic and asymptomatic periods.PATIENTS/METHODS:Two patients with typical KLS were admitted during symptomatic and asymptomatic periods to a research Sleep Disorders Center. Cerebrospinalfluid (CSF) hypocretin-1, histamine (HA), and its major metabolite tele-methylhistamine (t-MHA) levels were measured in two KLS patients in and out of episode.RESULTS:CSF biomarkers of hypothalamic dysfunction measured in two KLS patients in and out of episode revealed low hypocretin levels (within the narcolepsy-cataplexy range) during a hypersomnia episode in the more severe patient, and a 42% decrease (although within normal range) in the second patient. CSF HA and t-MHA measurements in and out of episode revealed a two-fold in-episode decrease in HA in the more severe patient, with no significant change for the second patient, nor for t-MHA levels.CONCLUSION:We reported reversible changes in CSF hypothalamic biomarkers in a typical patient with KLS that reinforces the hypothesis that in some patients KLS episodes may be caused by recurrent functional alterations of the hypothalamus

  • Kleine-Levin Syndrome in 120 patients: Differential diagnosis and long episodes
    'Wiley', 2015
    Co-Authors: Lavault Sophie, Dauvilliers Yves, Groos Elisabeth, Golmard Jean-louis, Brion Agnès, Lecendreux Michel, Franco Patricia, Arnulf Isabelle
    Abstract:

    International audienceOBJECTIVE:Kleine-Levin Syndrome is a rare disease characterized by recurrent episodes of hypersomnia with behavioral and cognitive disturbances. We aimed at describing the diagnosis procedure, risk factors, and severe forms.METHODS:In consecutive patients referred for suspected Kleine-Levin Syndrome, we detailed differential diagnoses, and atypical and secondary cases, compared typical patients with healthy subjects, and examined the characteristics of patients with prolonged (>30 days) episodes.RESULTS:Among 166 referred patients, 120 had typical primary Kleine-Levin Syndrome (Syndrome secondary to brain diseases; n = 4, atypical Syndrome, n = 7; differential diagnoses that were mostly psychiatric, n = 29; incomplete information, n = 6). The prevalence in France was 1.8 per million. The patients were often male (64%) and had more frequent birth and developmental abnormalities (45%) than controls (despite normal karyotypes), and most (80%) had teenage onset, with no difference between patients with prolonged (n = 34) and short (n = 85) episodes. In patients with prolonged episodes, the durations of the first episode (32 ± 33 vs 11 ± 6 days) and subsequent episodes were longer (mean episode duration = 23 ± 19 vs 10 ± 3 days) and the disease course tended to be longer (9 ± 6 vs 6 ± 4 years). During episodes, patients with prolonged episodes had shorter sleep time, higher levels of anxiety, increased agitation, and more feelings of disembodiment and amnesia. Between episodes, they were more tired, needed more naps, fell asleep more rapidly, and had higher anxiety/depression scores.INTERPRETATION:Mental disorders are frequent differential diagnoses of Kleine-Levin Syndrome. One-third of patients have prolonged (>1 month) episodes with more frequent immediate and long-term consequences of the disease, prompting therapeutic trials

  • Widespread Hypermetabolism in Symptomatic and Asymptomatic Episodes in Kleine-Levin Syndrome
    Public Library of Science, 2014
    Co-Authors: Dauvilliers Yves, Lopez Regis, Bayard Sophie, Comte Frederic, Zanca Michel, Peigneux Philippe
    Abstract:

    No reliable biomarkers are identified in KLS. However, few functional neuroimaging studies suggested hypoactivity in thalamic and hypothalamic regions during symptomatic episodes. Here, we investigated relative changes in regional brain metabolism in Kleine-Levin Syndrome (KLS) during symptomatic episodes and asymptomatic periods, as compared to healthy controls.-F-fluorodeoxy glucose positron emission tomography (PET) was obtained in baseline condition in all participants, and during symptomatic episodes in KLS patients. All participants were asked to remain fully awake during the whole PET procedure.Between state-comparisons in KLS disclosed higher metabolism in paracentral, precentral, and postcentral areas, supplementary motor area, medial frontal gyrus, thalamus and putamen during symptomatic episodes, and decreased metabolism in occipital and temporal gyri. As compared to healthy control subjects, KLS patients in the asymptomatic phase consistently exhibited significant hypermetabolism in a wide cortical network including frontal and temporal cortices, posterior cingulate and precuneus, with no detected hypometabolism. In symptomatic KLS episodes, hypermetabolism was additionally found in orbital frontal and supplementary motor areas, insula and inferior parietal areas, and right caudate nucleus, and hypometabolism in the middle occipital gyrus and inferior parietal areas.Our results demonstrated significant hypermetabolism and few hypometabolism in specific but widespread brain regions in drug-free KLS patients at baseline and during symptomatic episodes, highlighting the behavioral state-dependent nature of changes in regional brain activity in KLS

Emmanuel Mignot - One of the best experts on this subject based on the ideXlab platform.

  • a practical guide to the therapy of narcolepsy and hypersomnia Syndromes
    Neurotherapeutics, 2012
    Co-Authors: Emmanuel Mignot
    Abstract:

    Narcolepsy and other Syndromes associated with excessive daytime sleepiness can be challenging to treat. New classifications now distinguish narcolepsy/hypocretin deficiency (also called type 1 narcolepsy), a lifelong disorder with well-established diagnostic procedures and etiology, from other Syndromes with hypersomnolence of unknown causes. Klein-Levin Syndrome, a periodic hypersomnia associated with cognitive and behavioral abnormalities, is also considered a separate entity with separate therapeutic protocols. Non hypocretin-related hypersomnia Syndromes are diagnoses of exclusion. These diagnoses are only made after eliminating sleep deprivation, sleep apnea, disturbed nocturnal sleep, and psychiatric comorbidities as the primary cause of daytime sleepiness. The treatment of narcolepsy/hypocretin deficiency is well-codified, and involves pharmacotherapies using sodium oxybate, stimulants, and/or antidepressants, plus behavioral modifications. These therapies are almost always needed, and the risk-to-benefit ratio is clear, notably in children. Detailed knowledge of the pharmacological profile of each compound is needed to optimize use. Treatment for other Syndromes with hypersomnolence is more challenging and less codified. Preferably, therapy should be conservative (such as modafinil, atomoxetine, behavioral modifications), but it may have to be more aggressive (high-dose stimulants, sodium oxybate, etc.) on a case-by-case, empirical trial basis. As cause and evolution are unknown in these conditions, it is important to challenge diagnosis and therapy over time, keeping in mind the possibility of tolerance and the development of stimulant addiction. Kleine-Levin Syndrome is usually best left untreated, although lithium can be considered in severe cases with frequent episodes. Guidelines are provided based on the literature and personal experience of the author.

  • diagnosis disease course and management of patients with kleine levin Syndrome
    Lancet Neurology, 2012
    Co-Authors: Isabelle Arnulf, Thomas J Rico, Emmanuel Mignot
    Abstract:

    Summary Kleine-Levin Syndrome is a rare sleep disorder that mainly affects adolescents and is characterised by relapsing-remitting episodes of severe hypersomnia, cognitive impairment, apathy, derealisation, and psychiatric and behavioural disturbances. Boys are more frequently affected than girls. Just over half of patients have hyperphagia, are hypersexual (mainly boys), or have depressed mood (mainly girls), and 30% become anxious, delusional, and have hallucinations. Although some symptoms are similar to those in patients with encephalopathy, imaging and laboratory findings are unremarkable. The first episode of hypersomnia is often triggered by an infection, with relapses occurring every 1–12 months for a median of 14 years; disease duration can be much longer with childhood or adult onset than in patients with adolescent onset. Between episodes, patients generally have normal sleep patterns, cognition, mood, and eating habits. During episodes, electroencephalography might show diffuse or local slow activity. Functional imaging studies have revealed hypoactivity in thalamic and hypothalamic regions, and in the frontal and temporal lobes. Stimulants and mood stabilisers can be beneficial in the treatment of severe cases.

Landtblom Anne-marie - One of the best experts on this subject based on the ideXlab platform.

  • Neuroimaging in the Kleine-Levin Syndrome
    'Springer Science and Business Media LLC', 2018
    Co-Authors: Engström Maria, Latini Francesco, Landtblom Anne-marie
    Abstract:

    The purpose was to review the most recent literature on neuroimaging in the Kleine-Levin Syndrome (KLS). We aimed to investigate if frontotemporal and thalamic dysfunction are key KLS signatures, and if recent research indicates other brain networks of interest that elucidate KLS symptomatology and aetiology. In a comprehensive literature search, we found 12 original articles published 2013-2018. Most studies report deviations related to cerebral perfusion, glucose metabolism, or blood-oxygen-level-dependent responses in frontotemporal areas and/or the thalamus. Studies also report dysfunction in the temporoparietal junction and the oculomotor network that also were related to clinical parameters. We discuss these findings based on recent research on thalamocortical networks and brain stem white matter tracts. The hypothesis of frontotemporal and thalamic involvement in KLS was confirmed, and additional findings in the temporoparietal junction and the oculomotor system suggest a broader network involvement, which can be investigated by future high-resolution and multimodal imaging

  • New hypothesis on pontine-frontal eye field connectivity in Kleine-Levin Syndrome
    'Wiley', 2016
    Co-Authors: Engström Maria, Landtblom Anne-marie, Karlsson Thomas
    Abstract:

    Previous studies have indicated involvement of the thalamus and the pons in Kleine-Levin Syndrome. In the present study, functional connectivity of the thalamus and the pons was investigated in asymptomatic patients with Kleine-Levin Syndrome and healthy controls. Twelve patients and 14 healthy controls were investigated by functional magnetic resonance imaging during rest. Resting state images were analysed using seed regions of interest in the thalamus and the pons. The results showed significantly lower functional connectivity between the pons and the frontal eye field in persons with Kleine-Levin Syndrome compared with healthy controls. There were no connectivity differences involving the thalamus. Based on these findings, a relation is proposed between the sleep disorder Kleine-Levin Syndrome and cerebral control of eye movements, which in turn is related to visual attention and working memory. This hypothesis has to be tested in future studies of oculomotor control in Kleine-Levin Syndrome.Funding Agencies|KLS Foundation; Linkoping University; Linkoping University Hospital

  • Functional magnetic resonance imaging in narcolepsy and the Kleine-Levin Syndrome
    'Frontiers Media SA', 2014
    Co-Authors: Engström Maria, Hallböök Tove, Szakacs Attila, Karlsson Thomas, Landtblom Anne-marie
    Abstract:

    This work aims at reviewing the present state of the art when it comes to understanding the pathophysiology of narcolepsy and the Kleine-Levin Syndrome (KLS) from a neuroimaging point of view. This work also aims at discussing future perspectives of functional neuroimaging in these sleep disorders. We focus on functional magnetic resonance imaging (fMRI), which is a technique for in vivo measurements of brain activation in neuronal circuitries under healthy and pathological conditions. fMRI has significantly increased the knowledge on the affected neuronal circuitries in narcolepsy and the Kleine-Levin Syndrome. It has been shown that narcolepsy is accompanied with disturbances of the emotional and the closely related reward systems. In the Kleine Levin Syndrome, fMRI has identified hyperactivation of the thalamus as a potential biomarker that could be used in the diagnostic procedure. The fMRI findings in both narcolepsy and the Kleine-Levin Syndrome are in line with previous structural and functional imaging studies. We conclude that fMRI in combination with multi-modal imaging can reveal important details about the pathophysiology in narcolepsy and the Kleine-Levin Syndrome. In the future, fMRI possibly gives opportunities for diagnostic support and prediction of treatment response in individual patients

  • Reduced thalamic and pontine connectivity in Kleine–Levin Syndrome
    'Frontiers Media SA', 2014
    Co-Authors: Engström Maria, Karlsson Thomas, Landtblom Anne-marie
    Abstract:

    The Kleine–Levin Syndrome (KLS) is a rare sleep disorder, characterized by exceptionally long sleep episodes. The neuropathology of the Syndrome is unknown and treatment is often inadequate. The aim of the study was to improve understanding of the underlying neuropathology, related to cerebral networks, in KLS during sleep episodes. One patient with KLS and congenital nystagmus was investigated by resting state functional magnetic resonance imaging during both asymptomatic and hypersomnic periods. Fourteen healthy subjects were also investigated as control samples. Functional connectivity was assessed from seed regions of interest in the thalamus and the dorsal pons. Thalamic connectivity was normal in the asymptomatic patient whereas the connectivity between the brain stem, including dorsal pons, and the thalamus was diminished during hypersomnia. These results suggest that the patient’s nystagmus and hypersomnia might have their pathological origin in adjacent dorsal pontine regions. This finding provides additional knowledge of the cerebral networks involved in the neuropathology of this disabling disorder. Furthermore, these findings regarding a rare Syndrome have broad implications, and results could be of interest to researchers and clinicians in the whole field of sleep medicine

  • Low Thalamic NAA-Concentration Corresponds to Strong Neural Activation in Working Memory in Kleine-Levin Syndrome
    'Public Library of Science (PLoS)', 2013
    Co-Authors: Vigren Patrick, Engström Maria, Karlsson Thomas, Tisell Anders, Dahlqvist Leinhard Olof, Lundberg Peter, Landtblom Anne-marie
    Abstract:

    Background Kleine Levin Syndrome (KLS) is a rare disorder of periodic hypersomnia and behavioural disturbances in young individuals. It has previously been shown to be associated with disturbances of working memory (WM), which, in turn, was associated with higher activation of the thalamus with increasing WM load, demonstrated with functional magnetic resonance imaging (fMRI). In this study we aimed to further elucidate how these findings are related to the metabolism of the thalamus. Methods fMRI and magnetic resonance spectroscopy were applied while performing a WM task. Standard metabolites were examined: n-acetylaspartate (NAA), myo-inositol, choline, creatine and glutamate-glutamine. Fourteen KLS-patients and 15 healthy controls participated in the study. The patients with active disease were examined in asymptomatic periods. Results There was a statistically significant negative correlation between thalamic fMRI-activation and thalamic NAA, i.e., high fMRI-activation corresponded to low NAA-levels. This correlation was not seen in healthy controls. Thalamic levels of NAA in patients and controls showed no significant differences between the groups. None of the other metabolites showed any co-variation with fMRI-activiation. Conclusion This study shows negative correlation between NAA-levels and fMRI-activity in the left thalamus of KLS-patients while performing a WM task. This correlation could not be found in healthy control subjects, primarily interpreted as an effect of increased effort in the patient group upon performing the task. It might indicate a disturbance in the neuronal networks responsible for WM in KLS patients, resulting in higher effort at lower WM load, compared with healthy subjects. The general relationship between NAA and BOLD-signal is also discussed in the article

Nancy L Segal - One of the best experts on this subject based on the ideXlab platform.