Speech Cine SSFP with optical microphone synchronization and motion compensated reconstruction

International audienceDynamic imaging of the vocal tact is important for modeling speechthrough the acoustic-articulatory relation. The average duration of each sound isabout 80ms. Movements of each articulator, in particular the tongue, should becaptured with sufficient precision. Current clinical techniques use X-ray videofluoroscopy which involves ionizing radiation. Real-time MRI allows direct recordingof speech motion [1] but is intrinsically limited in terms of resolution and SNR.Synchronization of MRI with an acoustic device is possible [2] but requires motion ofvocal system to be highly reproducible. In this work we propose an optimized setupfor achieving dynamic MRI of speech with high spatial and temporal resolution basedon a combination of: an MR-compatible acoustic device allowing simultaneousrecording of speech during MRI; and a retrospectively gated, motion-compensatedimage reconstruction that can deal with the variability of the subject repeating thesame sentence over the acquisition

Long-Lasting Myocardial and Skeletal Muscle Damage Evidenced by Serial CMR During the First Year in COVID-19 Patients From the First Wave

International audienceIntroduction This observational CMR study aims to characterize left-ventricular (LV) damage, which may be specifically attributed to COVID-19 and is distant in time from the acute phase, through serial CMR performed during the first year in patients with no prior cardiac disease. Methods This study included consecutive patients without any prior history of cardiac disease but with a peak troponin-Ic > 50 ng/ml at the time of the first COVID-wave. All had a CMR in the first months after the acute phase, and some had an additional CMR at the end of the first year to monitor LV function, remodeling, and abnormalities evocative of myositis and myocarditis - i.e., increased T1/T2 relaxation times, increased extracellular volume (ECV), and delayed contrast enhancement. Results Nineteen consecutively admitted COVID-19 patients (17 men, median age 66 [57–71] years) were included. Eight (42%) had hypertension, six (32%) were obese, and 16 (84%) had suffered an acute respiratory distress syndrome. The 1 st CMR, recorded at a median 3.2 [interquartile range: 2.6–3.9] months from the troponin peak, showed (1) LV concentric remodeling in 12 patients (63%), (2) myocardial tissue abnormalities in 11 (58%), including 9 increased myocardial ECVs, and (3) 14 (74%) increased ECVs from shoulder skeletal muscles. The 2 nd CMR, obtained at 11.1 [11.0–11.7] months from the troponin peak in 13 patients, showed unchanged LV function and remodeling but a return to normal or below the normal range for all ECVs of the myocardium and skeletal muscles. Conclusion Many patients with no history of cardiac disease but for whom an increase in blood troponin-Ic ascertained COVID-19 induced myocardial damage exhibited signs of persistent extracellular edema at a median 3-months from the troponin peak, affecting the myocardium and skeletal muscles, which resolved within a one-year time frame. Associations with long-COVID symptoms need to be investigated on a larger scale now. Clinical Trial Registration NCT04753762 on the ClinicalTrials.gov site

Impact of Emergent Cervical Carotid Stenting in Tandem Occlusion Strokes Treated by Thrombectomy: A Review of the TITAN Collaboration

Introduction: Endovascular therapy has been shown to be an effective and safe treatment for tandem occlusion. The endovascular therapeutic strategies for tandem occlusions strokes have not been adequately evaluated and the best approach is still controversial. The TITAN (Thrombectomy in TANdem occlusions) registry was a result of a collaborative effort to identify the best therapeutic approach for acute ischemic stroke due to tandem lesion. In this review, we aim to summarize the main findings of the TITAN study and discuss the challenges of treatment for tandem occlusion in the era of endovascular thrombectomy.Methods: A review of the data from the multicenter international observational and non-randomized TITAN registry was performed. The TITAN registry included acute ischemic stroke patients with tandem lesions (proximal intracranial occlusion and cervical carotid artery occlusion or stenosis>90%) who were treated with thrombectomy with or without carotid artery stenting.Results: Prior intravenous thrombolysis and emergent cervical carotid stenting were associated with higher reperfusion (mTICI 2b-3 and mTICI 3) rates at the end of the intervention. Poor outcome did not occur more frequently after stenting than after conservative treatment of the cervical carotid lesion. Emergent carotid stenting with antithrombotic agents and intracranial thrombectomy yielded higher reperfusion rate and good outcome (90 day mRS 0–2) compared to other strategies (carotid artery stenting and thrombectomy without antithrombotic, angioplasty and thrombectomy, or thrombectomy alone). Pretreatment intravenous thrombolysis was not associated with increased risk of hemorrhagic complications. Likewise, periprocedural unfractionated heparin did not modify the efficacy and safety results. Etiology of carotid artery lesion (atherosclerosis vs. dissection) did not emerge as predictor of outcome or recanalization.Conclusion: Emergent stenting of the cervical carotid lesion with antithrombotic agents in conjunction to thrombectomy appears to be the best treatment strategy for acute ischemic strokes with tandem lesions. These findings will be further investigated in the ongoing randomized controlled TITAN trial

Développements méthodologiques et techniques pour le contrôle qualité en imagerie par résonance magnétique

De plus en plus utilisée en routine clinique, l'Imagerie par Résonance Magnétique (IRM) est très fréquemment associée à d'autres modalités d'imagerie médicale dans le cadre d'études multicentriques. Elle est également utilisée à des fins de quantification et sa technologie se complexifie, notamment avec l'utilisation croissante d'antennes en réseau phasé. Ces raisons contribuent à amplifier le besoin d'assurance qualité car il importe de surveiller les performances des appareils cliniques afin de se prémunir d'erreurs de diagnostic que leurs dérives peuvent entrainer. Des travaux, très tôt engagés sur le contrôle qualité (CQ) en IRM, ont posé les bases pour la conception d'objets-test et des mesures physiques nécessaires au suivi. Ces travaux ont aussi permis de dégager deux approches pour les procédures de CQ en IRM, à savoir des approches mono-objet et multi-objet. Les travaux menés poursuivent le premier objectif de développer une méthodologie de suivi périodique des appareils d'IRM qui soit pratique, peu chronophage, statistiquement robuste et compatible avec différents appareils. L'approche mono-objet issue des travaux de l'American College of Radiology a été choisie pour élaborer la procédure. Les travaux ont porté sur les principaux aspects du processus de réalisation des tests. La procédure hebdomadaire résultante, d'une durée de réalisation inférieure à 10 min, a été testée avec succès sur 6 sites disposant d'appareils de différentes gammes. Le deuxième objectif porte sur le contrôle spécifique des antennes en réseau phasé. Ceux-ci sont essentiellement caractérisés par deux paramètres qui ont été identifiés comme déterminants pour la reconstruction et la qualité des images. Il s'agit des profils de sensibilité des antennes et des corrélations en termes de bruit d'acquisition. Deux métriques ont été élaborées pour surveiller ces deux paramètres. Une technique alternative a également été développée pour calculer les covariances de bruit. Enfin, cette thèse propose quelques pistes pour mettre les outils de CQ au service d'applications cliniques ciblées. Les travaux engagés en ce sens ouvrent des perspectives intéressantes pour l'utilisation de techniques de CQ dans le cadre d'applications cliniques cibléesMagnetic Resonance Imaging (MRI) is increasingly being used in clinical routine and is frequently associated with different imaging modalities in multisite studies. Besides, MRI is becoming more complex with a growing use of phased-array coils. Hence there is a rising eagerness for quality assurance and quality control (QC). Indeed, monitoring MR systems is required in order to prevent from diagnostic errors which may be induced by drifts in the instrumentation. The ever first studies about MRI QC issue established the basis for designing test-objects and metrics which are required for monitoring the scanners. These works also resulted in two approaches for performing the testings : the first one is multi-object oriented and the second one is single-object oriented. The research conducted for this thesis are motivated by two objectives : the first one holds about designing a methodology for performing periodic monitoring of MR scanners. The procedure is required to be practical, shortly-timed, statistically robust, and system-independent. It was designed following the single-object approach promoted by the American College of Radiology. In order to fit the procedure with its specifications, all of its aspects were assessed. The resulting 10-minute weekly QC procedure was successfully tested on several MR facilities. The second goal of these works is about specifically assessing the performance of phased-array coils. Using these coils, two parameters were considered as being essential for image quality considerations, namely the sensitivity profiles and the noise covariance matrix. For monitoring these parameters, two metrics were designed in a way that they could be integrated within the weekly QC procedure. Besides, an alternative method was proposed for computing noise covariance matrices. As a matter of prospects, these doctoral works sought clinical applications which may take advantage of the techniques and methodology elaborated for QC purposes. There are interesting insights about using QC techniques in support of targeted clinical MR applicationsNANCY-INPL-Bib. électronique (545479901) / SudocSudocFranceF

Spectroscopie quantitative par résonance magnétique proton en conditions cliniques (étude de la variabilité d'un dispositif ERETIC et spectres de médicaments)

CAEN-BU Médecine pharmacie (141182102) / SudocSudocFranceF

Development and improvement of the diagnostic imaging tools for the characterization of tumor masses of the musculosheletal system

L'imagerie médicale joue un rôle majeur dans l'identification, la caractérisation et le bilan d'extension des lésions tumorales du système ostéo-articulaire. La grande majorité de ces néoplasies est bénigne et il est important de savoir les reconnaître et les distinguer des lésions malignes. Ces dernières ont un pronostic beaucoup plus sombre et sont l'objet d'une prise en charge nettement plus agressive. L'IRM est actuellement la technique de choix pour l'évaluation des tumeurs ostéo-articulaires. Malgré une très haute sensibilité pour la détection des tumeurs osseuses et des parties molles, un grand nombre de lésions identifiées ne sont pas caractérisables. Récemment des nouvelles techniques d'imagerie fonctionnelle sont apparues permettant une évaluation tumorale au niveau biochimique et cellulaire. Ces techniques, initialement conçues pour l'évaluation des tumeurs cérébrales comme la perfusion, la diffusion et la spectroscopie ont commencé à être utilisées pour l'évaluation des néoplasies ostéo-articulaires avec des résultats préliminaires prometteurs. Parallèlement, avec le développement en scanner de systèmes de détection à large surface et l'échographie de contraste, l'étude de la perfusion tumorale basée sur ces méthodes est plus accessible en pratique courante. L'imagerie fonctionnelle reste, néanmoins peu accessible en dehors de la recherche. Des difficultés techniques inhérentes à l'application clinique de ces nouvelles méthodes et l'hétérogénéité histologique des tumeurs ostéo-articulaires constituent encore un obstacle important. Dans ce travail la performance diagnostique de plusieurs méthodes d'imagerie fonctionnelle en pratique courante a été évaluée. En autre, des améliorations permettant une augmentation de la qualité d'image et une réduction des artéfacts des méthodes fonctionnelles ont été testées. Secondairement, les performances diagnostiques de différentes méthodes de perfusion tumorale (échographie, tomodensitométrie et imagerie par résonance magnétique) ont été comparéesMedical imaging plays a major role in the identification, characterization and staging of tumor lesions of the musculoskeletal system. The vast majority of these neoplasms are benign and it is important to recognize and distinguish them from malignant lesions. Malignant lesions carry a worse prognosis and are usually treated aggressively. MRI is currently the method of choice for evaluating musculoskeletal tumors. Despite a high sensitivity for the detection of bone and soft tissue tumors, a large number of identified lesions remain indeterminate in origin after imaging work-up. In recent years, new functional imaging techniques, which allow tumor evaluation in a biochemical and cellular level, have emerged. These techniques such as perfusion, diffusion weighted imaging and MR spectroscopy, originally designed for the evaluation of brain tumors, began to be used for the evaluation of musculoskeletal neoplasms with promising preliminary results. Meanwhile, with the development of wide area-detector CT systems and contrast enhanced ultrasound (CEUS) new ways of assessing tumor perfusion became available in clinical practice. Functional imaging nevertheless remains largely inaccessible outside research oriented imaging centers. The clinical application of these new methods is hindered by various factors, which include the great histological heterogeneity of musculoskeletal tumors and patient related technical difficulties. In this project, the diagnostic performance of several functional imaging methods in clinical practice was assessed. Additionally tools for image quality improvement and artifact reduction were tested. Finally, the diagnostic performance of different perfusion methods (ultrasound, computed tomography and magnetic resonance imaging) was comparedMETZ-SCD (574632105) / SudocNANCY1-Bib. numérique (543959902) / SudocNANCY2-Bibliotheque electronique (543959901) / SudocNANCY-INPL-Bib. électronique (545479901) / SudocSudocFranceF

Effects of Gender and Age on Self-reported Odor Imagery Ability

Introduction Odor imagery is known to be more difficult than any other modality of sensory imagery. Consequently, wide between-individuals variability can be found in odor imagery ability. Several studies have shown a positive relationship between olfactory performance and odor imagery ability. In the light of factors known to influence smelling ability, this study therefore investigated the effects of two factors - gender and age - known to influence smelling ability, on self-declared odor imagery ability in normosmic individuals. Methods Seven hundred and nine French participants were asked to complete the web version of the French Vividness of Olfactory Imagery Questionnaire (fVOIQ). General linear models were used to determine the contributions of gender and age to odor imagery vividness scores. Moreover, scores were compared between age intervals ranging from 18-30 years old to 60 + years old. Results Our findings reveal that at any age, men and women have the same odor imagery ability. Odor imagery ability in self-declared normosmic individuals improves with age until 50-60 years old, and beyond this point the often-reported age-related olfactory decay does not alter it. Conclusions These findings suggest a high contribution of daily olfactory experience to the development of this cognitive function, and a relationship with olfactory performance that appears less linear than hypothesized

Do individual constraints induce flexibility of visual field dependence following a virtual immersion? Effects of perceptive style and cybersickness

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First trimester screening for pre-eclampsia and intrauterine growth restriction using three-dimensional Doppler angiography (SPIRIT): protocol for a multicentre prospective study in nulliparous pregnant women

International audienceTo cite: Bertholdt C, Hossu G, Banasiak C, et al. First trimester screening for pre-eclampsia and intrauterine growth restriction using three-dimensional Doppler angiography (SPIRIT): protocol for a multicentre prospective study in nulliparous pregnant women. BMJ Open 2020;10:e037751

Optimizing z-axis coverage of abdominal CT scans of the urinary tract: a proposed alternative proximal landmark for acquisition planning

International audienceObjective: To evaluate an alternative method to reduce the acquisition coverage of urinary tract CT.Methods: This retrospective study included 365 abdominopelvic CT studies. Three radiographers simulated shortened acquisition coverages using three methods to determine the upper limit of the acquisition: Method 1 used the renal contours; Method 2 used the inferior margin of the 10th thoracic vertebra; and Method 3 used the point of intersection of the left diaphragmatic dome and the anterior margin of the vertebral bodies. Reductions in acquisition coverage and number of CT scans with a portion of the kidney excluded from the simulated reduced acquisition were compared between the three methods.Results: The mean ± standard deviation reduction of acquisition coverage for the three readers with Methods 1, 2 and 3 were 20.5 ± 4.8, 15.1 ± 6.5 and 18.2 ± 5.3%, respectively. Compared with Method 2, Method 3 allowed a mean scan length reduction of 3.6%. The proportions of CT scans with a portion of the kidney excluded from the simulated reduced acquisition with Methods 1, 2 and 3 and averaged over the three readers were 6.7, 0.7 and 1.4%, respectively, with no significant difference between Methods 2 and 3. Interreader and intrareader agreements were excellent with all methods, but interclass correlation coefficients were higher with Method 3.Conclusion: The method using the renal contours should not be used owing to its high proportion of kidneys with a portion excluded from the acquisition. Using the intersection of the left diaphragmatic dome and the anterior margin of the vertebral bodies for proximal landmark for urinary tract CT represents a new alternative method with a better reduction of scan length compared with the method using the inferior margin of T10 and with no significant increase in the number of kidneys with a portion excluded from the reduced acquisition. Advances in knowledge: A new method using the point of intersection of the left diaphragmatic dome and the anterior border of the vertebral bodies on the lateral scout radiograph is introduced to reduce the z-axis coverage of urinary tract CT scans