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  1. Article ; Online: Automated segmentation of deep brain nuclei using convolutional neural networks and susceptibility weighted imaging.

    Beliveau, Vincent / Nørgaard, Martin / Birkl, Christoph / Seppi, Klaus / Scherfler, Christoph

    Human brain mapping

    2021  Volume 42, Issue 15, Page(s) 4809–4822

    Abstract: The advent of susceptibility-sensitive MRI techniques, such as susceptibility weighted imaging (SWI), has enabled accurate in vivo visualization and quantification of iron deposition within the human brain. Although previous approaches have been ... ...

    Abstract The advent of susceptibility-sensitive MRI techniques, such as susceptibility weighted imaging (SWI), has enabled accurate in vivo visualization and quantification of iron deposition within the human brain. Although previous approaches have been introduced to segment iron-rich brain regions, such as the substantia nigra, subthalamic nucleus, red nucleus, and dentate nucleus, these methods are largely unavailable and manual annotation remains the most used approach to label these regions. Furthermore, given their recent success in outperforming other segmentation approaches, convolutional neural networks (CNN) promise better performances. The aim of this study was thus to evaluate state-of-the-art CNN architectures for the labeling of deep brain nuclei from SW images. We implemented five CNN architectures and considered ensembles of these models. Furthermore, a multi-atlas segmentation model was included to provide a comparison not based on CNN. We evaluated two prediction strategies: individual prediction, where a model is trained independently for each region, and combined prediction, which simultaneously predicts multiple closely located regions. In the training dataset, all models performed with high accuracy with Dice coefficients ranging from 0.80 to 0.95. The regional SWI intensities and volumes from the models' labels were strongly correlated with those obtained from manual labels. Performances were reduced on the external dataset, but were higher or comparable to the intrarater reliability and most models achieved significantly better results compared to multi-atlas segmentation. CNNs can accurately capture the individual variability of deep brain nuclei and represent a highly useful tool for their segmentation from SW images.
    MeSH term(s) Adult ; Aged ; Cerebellar Nuclei/diagnostic imaging ; Female ; Humans ; Image Processing, Computer-Assisted/methods ; Magnetic Resonance Imaging/methods ; Male ; Middle Aged ; Neural Networks, Computer ; Neuroimaging/methods ; Red Nucleus/diagnostic imaging ; Substantia Nigra/diagnostic imaging ; Subthalamic Nucleus/diagnostic imaging ; Young Adult
    Language English
    Publishing date 2021-07-29
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1197207-5
    ISSN 1097-0193 ; 1065-9471
    ISSN (online) 1097-0193
    ISSN 1065-9471
    DOI 10.1002/hbm.25604
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Preclinical Pediatric Care by Emergency Physicians: A Comparison of Trauma and Nontrauma Patients in a Population-Based Study in Austria.

    Vetschera, Anna / Beliveau, Vincent / Esswein, Katharina / Linzmeier, Klaus / Gozzi, Roland / Hohlrieder, Matthias / Simma, Burkhard

    Pediatric emergency care

    2022  Volume 38, Issue 7, Page(s) e1384–e1390

    Abstract: Objectives: Fewer than 10% of emergency medical system (EMS) calls concern children and adolescents younger than 18 years. Studies have shown that the preclinical care of children differs from that of adults regarding assessment, interventions, and ... ...

    Abstract Objectives: Fewer than 10% of emergency medical system (EMS) calls concern children and adolescents younger than 18 years. Studies have shown that the preclinical care of children differs from that of adults regarding assessment, interventions, and monitoring. The aims of this study were to describe the preclinical care and emergency transport of pediatric patients in Vorarlberg, Austria and to compare trauma and nontrauma cases.
    Methods: This is a population-based study, analyzing medical records of EMS calls to children and adolescents. We received all patient records of EMS calls to children and adolescents younger than 18 years (n = 4390 in total) from the 2 local EMS providers, the Red Cross Vorarlberg and the Austrian Mountain Rescue Service (Christophorus 8 and Gallus 1) covering a study period of 7 years, from 2013 to 2019. The record data were extracted by automation with an in-house program and subsequently anonymized. Statistical analyses were performed with SPSS Statistics.
    Results: During the study period, 7.9% of all EMS calls concerned children and adolescents younger than 18 years. For our study, 3761 records were analyzed and 1270 trauma cases (33.8%) were identified. The most common injuries were injuries of the extremities and traumatic brain injury. The frequency of National Advisory Committee of Aeronautics Scores of 4 or higher was 17.7%, similar for all age groups and for trauma as well as nontrauma patients. Mean Glasgow Coma Scale scores were higher in the trauma group than in the nontrauma group (14.2 vs 11.2). In 62.9% of all patients, 1 or more vital parameters were documented. A majority of these values was in the pathologic range for the respective age group. The rate of pulsoxymetry monitoring during transport was low (42.1% in trauma and 30.3% in nontrauma patients) and decreased significantly with patient age. Moreover, while the placing of intravenous lines and monitoring during transport were significantly more frequent in trauma patients, the administration of medication or oxygen was significantly more frequent in nontrauma patients.
    Conclusions: The pediatric population lacks assessments and monitoring in preclinical care, especially the youngest children and nontrauma patients, although emergency severity scores are similar.
    MeSH term(s) Adolescent ; Adult ; Austria/epidemiology ; Child ; Emergency Medical Services ; Glasgow Coma Scale ; Humans ; Physicians ; Retrospective Studies
    Language English
    Publishing date 2022-06-10
    Publishing country United States
    Document type Journal Article
    ZDB-ID 632588-9
    ISSN 1535-1815 ; 0749-5161
    ISSN (online) 1535-1815
    ISSN 0749-5161
    DOI 10.1097/PEC.0000000000002759
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: HFP-QSMGAN: QSM from homodyne-filtered phase images.

    Beliveau, Vincent / Birkl, Christoph / Stefani, Ambra / Gizewski, Elke R / Scherfler, Christoph

    Magnetic resonance in medicine

    2022  Volume 88, Issue 3, Page(s) 1255–1262

    Abstract: Purpose: Homodyne filtering is a standard preprocessing step in the estimation of SWI. Unfortunately, SWI is not quantitative, and QSM cannot be accurately estimated from filtered phase images. Compared with gradient-echo sequences suitable for ... ...

    Abstract Purpose: Homodyne filtering is a standard preprocessing step in the estimation of SWI. Unfortunately, SWI is not quantitative, and QSM cannot be accurately estimated from filtered phase images. Compared with gradient-echo sequences suitable for computing QSM, SWI is more readily available and is often the only susceptibility-sensitive sequence acquired in the clinical setting. In this project, we aimed to quantify susceptibility from the homodyne-filtered phase (HFP), acquired for computing susceptibility-weighted images, using convolutional neural networks to solve the compounded problem of (1) computing the solution to the inverse dipole problem, and (2) compensating for the effects of the homodyne filtering.
    Methods: Two convolutional neural networks, the U-Net and a modified QSMGAN architecture (HFP-QSMGAN), were trained to predict QSM maps at different TEs from HFP images. The QSM maps were quantified from a gradient-echo sequence acquired in the same individuals using total generalized variation (TGV)-QSM. The QSM maps estimated directly from the HFP were also included for comparison. Voxel-wise predictions and, importantly, regional predictions of susceptibility with adjustment to a reference region, were compared.
    Results: Our results indicate that the U-Net model provides more accurate voxel-wise predictions of susceptibility compared with HFP-QSMGAN and HFP-QSM. However, regional estimates of susceptibility predicted by HFP-QSMGAN are more strongly correlated with the values from TGV-QSM compared with those of U-Net and HFP-QSM.
    Conclusion: Accurate prediction of susceptibility can be achieved from filtered SWI phase using convolutional neural networks.
    MeSH term(s) Brain/diagnostic imaging ; Humans ; Magnetic Resonance Imaging/methods
    Language English
    Publishing date 2022-04-05
    Publishing country United States
    Document type Journal Article
    ZDB-ID 605774-3
    ISSN 1522-2594 ; 0740-3194
    ISSN (online) 1522-2594
    ISSN 0740-3194
    DOI 10.1002/mrm.29260
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Revisiting brain iron deficiency in restless legs syndrome using magnetic resonance imaging.

    Beliveau, Vincent / Stefani, Ambra / Birkl, Christoph / Kremser, Christian / Gizewski, Elke R / Högl, Birgit / Scherfler, Christoph

    NeuroImage. Clinical

    2022  Volume 34, Page(s) 103024

    Abstract: Study objectives: Studies on brain iron content in restless legs syndrome (RLS) using magnetic resonance imaging (MRI) are heterogeneous. In this study, we sought to leverage the availability of a large dataset including a range of iron-sensitive MRI ... ...

    Abstract Study objectives: Studies on brain iron content in restless legs syndrome (RLS) using magnetic resonance imaging (MRI) are heterogeneous. In this study, we sought to leverage the availability of a large dataset including a range of iron-sensitive MRI techniques to reassess the association between brain iron content and RLS with added statistical power and to compare these results to previous studies.
    Methods: The relaxation rates R
    Results: In our cohort, RLS patients had increased R
    Conclusions: Normal and increased iron content of subcortical brain areas detected in this study is not in line with the hypothesis of reduced brain iron storage, but favors CSF investigations and post mortem studies indicating alteration of brain iron mobilization and homeostasis in RLS.
    MeSH term(s) Brain/pathology ; Humans ; Iron/metabolism ; Iron Deficiencies ; Magnetic Resonance Imaging ; Restless Legs Syndrome/diagnostic imaging
    Chemical Substances Iron (E1UOL152H7)
    Language English
    Publishing date 2022-04-26
    Publishing country Netherlands
    Document type Journal Article ; Meta-Analysis ; Research Support, Non-U.S. Gov't
    ZDB-ID 2701571-3
    ISSN 2213-1582 ; 2213-1582
    ISSN (online) 2213-1582
    ISSN 2213-1582
    DOI 10.1016/j.nicl.2022.103024
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Investigating the Migraine Cycle over 21 Consecutive Days Using Proton Magnetic Resonance Spectroscopy and Resting-State fMRI: A Pilot Study.

    Filippi, Vera / Steiger, Ruth / Beliveau, Vincent / Frank, Florian / Kaltseis, Katharina / Gizewski, Elke R / Broessner, Gregor

    Brain sciences

    2022  Volume 12, Issue 5

    Abstract: Recent neuroimaging studies have revealed important aspects of the underlying pathophysiological mechanisms of migraine suggesting abnormal brain energy metabolism and altered functional connectivity. Proton magnetic resonance spectroscopy (1H-MRS) ... ...

    Abstract Recent neuroimaging studies have revealed important aspects of the underlying pathophysiological mechanisms of migraine suggesting abnormal brain energy metabolism and altered functional connectivity. Proton magnetic resonance spectroscopy (1H-MRS) studies investigated migraine patients in the interictal or ictal state. This first-of-its-kind study aimed to investigate the whole migraine cycle using 1H-MRS and resting-state functional magnetic resonance imaging (fMRI). A migraine patient underwent 1H-MRS and resting-state fMRI for 21 consecutive days, regardless of whether he was in an interictal or ictal state. Metabolite ratios were assessed and compared to the intrinsic connectivity of subcortical brain areas. Probable migraine phase-dependent changes in N-acetyl aspartate (NAA)/total creatine (tCr) and choline (Cho)/tCr levels are found in the left occipital lobe and left basal ganglia. NAA reflects neuronal integrity and Cho cellular membrane turnover. Such abnormalities may increase the susceptibility to excitatory migraine triggers. Functional connectivity between the right hippocampus and right or left pallidum was strongly correlated to the NAA/Cho ratio in the right thalamus, suggesting neurochemical modulation of these brain areas through thalamic connections. To draw statistically significant conclusions a larger cohort is needed.
    Language English
    Publishing date 2022-05-14
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2651993-8
    ISSN 2076-3425
    ISSN 2076-3425
    DOI 10.3390/brainsci12050646
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Generalizability of treatment outcome prediction in major depressive disorder using structural MRI: A NeuroPharm study.

    Beliveau, Vincent / Hedeboe, Ella / Fisher, Patrick M / Dam, Vibeke H / Jørgensen, Martin B / Frokjaer, Vibe G / Knudsen, Gitte M / Ganz, Melanie

    NeuroImage. Clinical

    2022  Volume 36, Page(s) 103224

    Abstract: Brain morphology has been suggested to be predictive of drug treatment outcome in major depressive disorders (MDD). The current study aims at evaluating the performance of pretreatment structural brain magnetic resonance imaging (MRI) measures in ... ...

    Abstract Brain morphology has been suggested to be predictive of drug treatment outcome in major depressive disorders (MDD). The current study aims at evaluating the performance of pretreatment structural brain magnetic resonance imaging (MRI) measures in predicting the outcome of a drug treatment of MDD in a large single-site cohort, and, importantly, to assess the generalizability of these findings in an independent cohort. The random forest, boosted trees, support vector machines and elastic net classifiers were evaluated in predicting treatment response and remission following an eight week drug treatment of MDD using structural brain measures derived with FastSurfer (FreeSurfer). Models were trained and tested within a nested cross-validation framework using the NeuroPharm dataset (n = 79, treatment: escitalopram); their generalizability was assessed using an independent clinical dataset, EMBARC (n = 64, treatment: sertraline). Prediction of antidepressant treatment response in the Neuropharm cohort was statistically significant for the random forest (p = 0.048), whereas none of the models could significantly predict remission. Furthermore, none of the models trained using the entire NeuroPharm dataset could significantly predict treatment outcome in the EMBARC dataset. Although our primary findings in the NeuroPharm cohort support some, but limited value in using pretreatment structural brain MRI to predict drug treatment outcome in MDD, the models did not generalize to an independent cohort suggesting limited clinical applicability. This study emphasizes the importance of assessing model generalizability for establishing clinical utility.
    Language English
    Publishing date 2022-10-10
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 2701571-3
    ISSN 2213-1582 ; 2213-1582
    ISSN (online) 2213-1582
    ISSN 2213-1582
    DOI 10.1016/j.nicl.2022.103224
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Characterization and diagnostic potential of R

    Beliveau, Vincent / Müller, Christoph / Steiger, Ruth / Gizewski, Elke R / Poewe, Werner / Seppi, Klaus / Scherfler, Christoph

    Parkinsonism & related disorders

    2022  Volume 101, Page(s) 43–48

    Abstract: Introduction: Iron accumulation in subcortical brain nuclei has been shown to be differentially increased in atypical parkinsonian disorders. It is unclear whether the patterns of iron accumulation are consistent between variants of progressive ... ...

    Abstract Introduction: Iron accumulation in subcortical brain nuclei has been shown to be differentially increased in atypical parkinsonian disorders. It is unclear whether the patterns of iron accumulation are consistent between variants of progressive supranuclear palsy (PSP) and their diagnostic utility in early to moderately advanced stages of the diseases.
    Methods: Brain iron content (R
    Results: Significant group differences in R
    Conclusion: Iron accumulation in subcortical brain nuclei has distinct correlated patterns in PSP-P and PSP-RS, which could be reflecting different pathophysiological mechanisms. Increased iron content in these nuclei appears to be a predictor for atypical parkinsonian disorders such as PSP and MSA. Further studies are required to reproduce this finding and elucidate the evolution of these patterns over the course of the disease.
    MeSH term(s) Humans ; Iron ; Magnetic Resonance Imaging/methods ; Multiple System Atrophy/diagnostic imaging ; Multiple System Atrophy/pathology ; Parkinson Disease/diagnostic imaging ; Parkinson Disease/pathology ; Parkinsonian Disorders/diagnostic imaging ; Parkinsonian Disorders/pathology ; Supranuclear Palsy, Progressive/diagnosis
    Chemical Substances Iron (E1UOL152H7)
    Language English
    Publishing date 2022-06-30
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1311489-x
    ISSN 1873-5126 ; 1353-8020
    ISSN (online) 1873-5126
    ISSN 1353-8020
    DOI 10.1016/j.parkreldis.2022.06.021
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Conference proceedings: [No title information]

    Filippi, Vera / Brössner, Gregor / Frank, Florian / Kaltseis, Katharina / Steiger, Ruth / Gizewski, Elke / Beliveau, Vincent

    Nervenheilkunde

    2022  Volume 41, Issue 05

    Event/congress 8. Dreiländertagung - Kopfschmerz, Lindau (Bodensee), 2022-05-12
    Language German
    Publishing date 2022-04-01
    Publisher Georg Thieme Verlag
    Publishing place Stuttgart ; New York
    Document type Article ; Conference proceedings
    ZDB-ID 2223503-6
    ISSN 2567-5788 ; 0722-1541
    ISSN (online) 2567-5788
    ISSN 0722-1541
    DOI 10.1055/s-0042-1745699
    Database Thieme publisher's database

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  9. Article ; Online: False positive rates in positron emission tomography (PET) voxelwise analyses.

    Ganz, Melanie / Nørgaard, Martin / Beliveau, Vincent / Svarer, Claus / Knudsen, Gitte M / Greve, Douglas N

    Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism

    2020  Volume 41, Issue 7, Page(s) 1647–1657

    Abstract: Issues with inflated false positive rates (FPRs) in brain imaging have recently received significant attention. However, to what extent FPRs present a problem for voxelwise analyses of Positron Emission Tomography (PET) data remains unknown. In this work, ...

    Abstract Issues with inflated false positive rates (FPRs) in brain imaging have recently received significant attention. However, to what extent FPRs present a problem for voxelwise analyses of Positron Emission Tomography (PET) data remains unknown. In this work, we evaluate the FPR using real PET data under group assignments that should yield no significant results after correcting for multiple comparisons. We used data from 159 healthy participants, imaged with the serotonin transporter ([
    MeSH term(s) Algorithms ; Brain/diagnostic imaging ; Brain/metabolism ; False Positive Reactions ; Healthy Volunteers ; Humans ; Positron-Emission Tomography/methods ; Radiopharmaceuticals/metabolism ; Receptors, Serotonin, 5-HT4/metabolism ; Serotonin Plasma Membrane Transport Proteins/metabolism
    Chemical Substances Radiopharmaceuticals ; Serotonin Plasma Membrane Transport Proteins ; Receptors, Serotonin, 5-HT4 (158165-40-3)
    Language English
    Publishing date 2020-11-26
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 604628-9
    ISSN 1559-7016 ; 0271-678X
    ISSN (online) 1559-7016
    ISSN 0271-678X
    DOI 10.1177/0271678X20974961
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Somatostatin receptor subtype expression and radiomics from DWI-MRI represent SUV of [68Ga]Ga-DOTATOC PET in patients with meningioma.

    Iglseder, Sarah / Iglseder, Anna / Beliveau, Vincent / Heugenhauser, Johanna / Gizewski, Elke R / Kerschbaumer, Johannes / Stockhammer, Guenther / Uprimny, Christian / Virgolini, Irene / Dudas, Jozsef / Nevinny-Stickel, Meinhard / Nowosielski, Martha / Scherfler, Christoph

    Journal of neuro-oncology

    2023  Volume 164, Issue 3, Page(s) 711–720

    Abstract: Objective: This retrospective study aimed to analyse the correlation between somatostatin receptor subtypes (SSTR 1-5) and maximum standardized uptake value (SUV: Method: The study included 51 patients who underwent MRI and [68Ga]Ga-DOTATOC PET ... ...

    Abstract Objective: This retrospective study aimed to analyse the correlation between somatostatin receptor subtypes (SSTR 1-5) and maximum standardized uptake value (SUV
    Method: The study included 51 patients who underwent MRI and [68Ga]Ga-DOTATOC PET before meningioma surgery. SUV
    Results: The random forest regression model successfully predicted SUV
    Conclusion: SSTR subtypes 2A, 2B, and 5 correlated significantly with SUV
    MeSH term(s) Humans ; Octreotide ; Meningioma/diagnostic imaging ; Meningioma/surgery ; Receptors, Somatostatin/analysis ; Receptors, Somatostatin/metabolism ; Retrospective Studies ; Positron-Emission Tomography/methods ; Magnetic Resonance Imaging ; Meningeal Neoplasms/diagnostic imaging ; Meningeal Neoplasms/surgery ; Organometallic Compounds
    Chemical Substances Edotreotide (U194AS08HZ) ; Octreotide (RWM8CCW8GP) ; Receptors, Somatostatin ; Organometallic Compounds
    Language English
    Publishing date 2023-09-14
    Publishing country United States
    Document type Journal Article
    ZDB-ID 604875-4
    ISSN 1573-7373 ; 0167-594X
    ISSN (online) 1573-7373
    ISSN 0167-594X
    DOI 10.1007/s11060-023-04414-3
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