67 research outputs found
A Rare Case of Radiologically Not Distinguishable Coexistent Meningioma and Vestibular Schwannoma in the Cerebellopontine Angle – Case Report and Literature Review
Background: The simultaneous occurrence of cerebellopontine angle (CPA) meningioma and vestibular schwannoma (VS) in the absence of neurofibromatosis type 2 or history of irradiation is very rare. We report a case with coexistent CPA meningioma and VS, which were radiologically not distinguishable in preoperative imaging. Case Description: A 46-year-old female presented with acute hearing loss, tinnitus and gait ataxia. Otorhinolaryngological diagnostic workup and imaging studies showed an intra- and extrameatal homogenous contrast enhancing lesion. The neuroradiological diagnosis was VS. The patient was operated via the retrosigmoid approach. Intraoperatively two distinct tumors were found: a small, mainly intrameatally located VS and a larger meningioma originating from the dura of the petrous bone. Both tumors were completely microsurgically removed. The patient experienced no new neurological deficit after surgery; particularly facial nerve function was completely preserved. Histopathological examination revealed a fibromatous meningioma and a VS, respectively. Conclusions: The coincidental occurrence of CPA meningioma and VS is very rare. Careful interpretation of imaging studies before surgery is crucial. Even such rare cases should be kept in mind when discussing the therapeutic options with the patient. More studies are needed for a better understanding of mechanisms leading to multiple tumor growth
Recalage et mise en correspondance d’images tomographiques et de projection: Résultats préliminaires d’une solution hybride en radiochirurgie
A new method for 2D/3D registration, applied to Magnetic Resonance Imaging (3D) and to X-Ray angiography (2D), has
been adapted and used for planning treatment in radiosurgery. The imaging flow needed for planning radiosurgery is
considerable and using registration technique would make lighter the imaging protocol without restricting planning. We
describe the preliminary results of the evaluation giving criteria to compare registration technique and localization using
stereotactic frame, which is the gold standard method. Preliminary results obtained during this first step in validating
registration put forward which kind of MRI sequence are more suitable to registration.Une méthode de recalage d’images multimodales 2D/3D entre Imagerie par Résonance Magnétique (3D) et
à l’angiographie par rayons X (2D) est appliquée à la planification dosimétrique en radiochirurgie. Le flux d’images
nécessaires à la réalisation du traitement en radiochirurgie est considérable. La fusion de ces images
multimodales dans un espace commun est requise pour la planification. Ainsi, elles nécessitent d’être acquises en
utilisant un référentiel dit «stéréotaxique». Cependant, l’utilisation d’algorithmes de recalage dans la phase de
planification permet de simplifier les procédures d’imagerie en diminuant l’usage du cadre sans contraindre la
planification. Nous proposons ici les résultats préliminaires de l’application du recalage dans un contexte
radiochirurgical par comparaison avec la méthode basée sur un repérage stéréotaxique qui constitue le gold
standard. Les résultats préliminaires obtenus lors de cette première phase de validation permettent de conclure
sur la compatibilité de certaines séquences d’images IRM avec le recalage d’images tomographique et de
projectio
Time-resolved 3D contrast-enhanced MRA with GRAPPA on a 1.5-T system for imaging of craniocervical vascular disease: initial experience
Introduction: For three-dimensional (3D) imaging with magnetic resonance angiography (MRA) of the cerebral and cervical circulation, both a high temporal and a high spatial resolution with isovolumetric datasets are of interest. In an initial evaluation, we analyzed the potential of contrast-enhanced (CE) time-resolved 3D-MRA as an adjunct for neurovascular MR imaging. Methods: In ten patients with various cerebrovascular disorders and vascularized tumors in the cervical circulation, high-speed MR acquisition using parallel imaging with the GeneRalized Autocalibrating Partially Parallel Acquisitions (GRAPPA) algorithm on a 1.5-T system with a temporal resolution of 1.5s per dataset and a nearly isovolumetric spatial resolution was applied. The results were assessed and compared with those from conventional MRA and digital subtraction angiography (DSA). Results: CE time-resolved 3D-MRA enabled the visualization and characterization of high-flow arteriovenous shunts in cases of vascular malformations or hypervascularized tumors. In steno-occlusive disease, the method provided valuable additional information about altered vessel perfusion compared to standard MRA techniques such as time-of-flight (TOF) MRA. The use of a nearly isovolumetric voxel size allowed a free-form interrogation of 3D datasets. Its comparatively low spatial resolution was found to be the major limitation. Conclusion: In this preliminary analysis, CE time-resolved 3D-MRA was revealed to be a promising complementary MRA sequence that enabled the visualization of contrast flow dynamics in various types of neurovascular disorders and vascularized cervical tumor
Hemodynamic effects of intraoperative 30% versus 80% oxygen concentrations: an exploratory analysis
BackgroundSupplemental oxygen leads to an increase in peripheral vascular resistance which finally increases systemic blood pressure in healthy subjects and patients with coronary artery disease, heart failure, undergoing heart surgery, and with sepsis. However, it is unknown whether this effect can also be observed in anesthetized patients having surgery. Thus, we evaluated in this exploratory analysis of a randomized controlled trial the effect of 80% versus 30% oxygen on intraoperative blood pressure and heart rate.MethodsWe present data from a previous study including 258 patients, who were randomized to a perioperative inspiratory FiO2 of 0.8 (128 patients) versus 0.3 (130 patients) for major abdominal surgery. Continuous arterial blood pressure values were recorded every three seconds and were exported from the electronic anesthesia record system. We calculated time-weighted average (TWA) and Average Real Variability (ARV) of mean arterial blood pressure and of heart rate.ResultsThere was no significant difference in TWA of mean arterial pressure between the 80% (80 mmHg [76, 85]) and 30% (81 mmHg [77, 86]) oxygen group (effect estimate −0.16 mmHg, CI –1.83 to 1.51; p = 0.85). There was also no significant difference in TWA of heart rate between the 80 and 30% oxygen group (median TWA of heart rate in the 80% oxygen group: 65 beats.min−1 [58, 72], and in the 30% oxygen group: 64 beats.min−1 [58; 70]; effect estimate: 0.12 beats.min−1, CI –2.55 to 2.8, p = 0.94). Also for ARV values, no significant differences between groups could be detected.ConclusionIn contrast to previous results, we did not observe a significant increase in blood pressure or a significant decrease in heart rate in patients, who received 80% oxygen as compared to patients, who received 30% oxygen during surgery and for the first two postoperative hours. Thus, hemodynamic effects of supplemental oxygen might play a negligible role in anesthetized patients.Clinical Trail Registrationhttps://clinicaltrials.gov/ct2/show/NCT03366857?term=vienna&cond=oxygen&draw=2&rank=
GREAT — a randomized aneurysm trial. Design of a randomized controlled multicenter study comparing HydroSoft/HydroFrame and bare platinum coils for endovascular aneurysm treatment
International audienceThe effectiveness of a hybrid hydrogel platinum detachable coil (HydroCoil; MicroVention Inc., Tustin, CA) for endovascular aneurysm treatment has been proven in a recently published RCT. Due to technical restrictions (coil stiffness, time restriction for placement), the HydroSoft coil as well as a corresponding 3D framing coil, the HydroFrame coil (MicroVention Inc., Tustin, CA), a class of new softer coils containing less hydrogel and swelling more slowly than the HydroCoil, have been developed and brought to clinical practice. The present study aims to compare the effectiveness of endovascular aneurysm treatment with coil embolization between patients allocated HydroSoft/HydroFrame versus bare platinum coiling. GREAT is a randomized, controlled, multicentre trial in patients bearing cerebral aneurysms to be treated by coil embolization. Eligible patients were randomized to either coil embolization with HydroSoft/HydroFrame coils (>50 % of administered coil length), or bare platinum coils. Inclusion criteria were as follows: age 18-75, ruptured aneurysm (WFNS 1-3) and unruptured aneurysm with a diameter between 4 and 12 mm. Anatomy such that endovascular coil occlusion deemed possible and willingness of the neurointerventionalist to use either HydroSoft/HydroFrame or bare platinum coils. Exclusion criteria were as follows: aneurysms previously treated by coiling or clipping. Primary endpoint is a composite of major aneurysm recurrence on follow-up angiography and poor clinical outcome (modified Rankin scale 3 or higher), both assessed at 18 months post treatment. Risk differences for poor outcomes will be estimated in a modified intention-to-treat analysis stratified by rupture status (DRKS-ID: DRKS00003132)
Effect of extracranial lesion severity on outcome of endovascular thrombectomy in patients with anterior circulation tandem occlusion: analysis of the TITAN registry
Introduction Endovascular treatment (EVT) for tandem occlusion (TO) of the anterior circulation is complex but effective. The effect of extracranial internal carotid artery (EICA) lesion severity on the outcomes of EVT is unknown. In this study we investigated the effect of EICA lesion severity on the outcomes of tandem occlusion EVT. Methods A multicenter retrospective TITAN (Thrombectomy In TANdem lesions) study that included 18 international endovascular capable centers was performed. Patients who received EVT for atherosclerotic TO with or without EICA lesion intervention were included. Patients were divided into two groups based on the EICA lesion severity (high-grade stenosis (>= 90% North American Symptomatic Carotid Endarterectomy Trial) vs complete occlusion). Outcome measures included the 90-day clinical outcome (modified Rankin Scale score (mRS)), angiographic reperfusion (modified Thrombolysis In Cerebral Ischemia (mTICI) at the end of the procedure), procedural complications, and intracranial hemorrhage at 24 hours follow-up. Results A total of 305 patients were included in the study, of whom 135 had complete EICA occlusion and 170 had severe EICA stenosis. The EICA occlusion group had shorter mean onset-to-groin time (259 +/- 120 min vs 305 +/- 202 min;p=0.037), more patients with diabetes, and fewer with hyperlipidemia. With respect to the outcome, mTICI 2b-3 reperfusion was lower in the EICA occlusion group (70% vs 81%;p=0.03). The favorable outcome (90-day mRS 0-2), intracerebral hemorrhage and procedural complications were similar in both groups. Conclusion Atherosclerotic occlusion of the EICA in acute tandem strokes was associated with a lower rate of mTICI 2b-3 reperfusion but similar functional and safety outcomes when compared with high-grade EICA stenosis
Measuring the burden of infodemics : summary of the methods and results of the fifth WHO infodemic management conference
Background: An infodemic is excess information, including false or misleading information, that spreads in digital and physical
environments during a public health emergency. The COVID-19 pandemic has been accompanied by an unprecedented global
infodemic that has led to confusion about the benefits of medical and public health interventions, with substantial impact on
risk-taking and health-seeking behaviors, eroding trust in health authorities and compromising the effectiveness of public health
responses and policies. Standardized measures are needed to quantify the harmful impacts of the infodemic in a systematic and
methodologically robust manner, as well as harmonizing highly divergent approaches currently explored for this purpose. This
can serve as a foundation for a systematic, evidence-based approach to monitoring, identifying, and mitigating future infodemic
harms in emergency preparedness and prevention.
Objective: In this paper, we summarize the Fifth World Health Organization (WHO) Infodemic Management Conference
structure, proceedings, outcomes, and proposed actions seeking to identify the interdisciplinary approaches and frameworks
needed to enable the measurement of the burden of infodemics.
Methods: An iterative human-centered design (HCD) approach and concept mapping were used to facilitate focused discussions
and allow for the generation of actionable outcomes and recommendations. The discussions included 86 participants representing
diverse scientific disciplines and health authorities from 28 countries across all WHO regions, along with observers from civil
society and global public health–implementing partners. A thematic map capturing the concepts matching the key contributing
factors to the public health burden of infodemics was used throughout the conference to frame and contextualize discussions.
Five key areas for immediate action were identified.
Results: The 5 key areas for the development of metrics to assess the burden of infodemics and associated interventions included
(1) developing standardized definitions and ensuring the adoption thereof; (2) improving the map of concepts influencing the
burden of infodemics; (3) conducting a review of evidence, tools, and data sources; (4) setting up a technical working group; and
(5) addressing immediate priorities for postpandemic recovery and resilience building. The summary report consolidated group input toward a common vocabulary with standardized terms, concepts, study designs, measures, and tools to estimate the burden
of infodemics and the effectiveness of infodemic management interventions.
Conclusions: Standardizing measurement is the basis for documenting the burden of infodemics on health systems and population
health during emergencies. Investment is needed into the development of practical, affordable, evidence-based, and systematic
methods that are legally and ethically balanced for monitoring infodemics; generating diagnostics, infodemic insights, and
recommendations; and developing interventions, action-oriented guidance, policies, support options, mechanisms, and tools for
infodemic managers and emergency program managers.peer-reviewe
Zur Integration der funktionellen Magnetresonanztomographie in die navigierte Therapie cerebraler Tumoren
Zusammenfassung Einleitung: Die Kraniotomie mit umfassender Tumorresektion bleibt Therapie der Wahl zur Behandlung von Hirntumoren. Bei der geforderten Radikalität des therapeutischen Vorgehens kommt der präoperativen Lokalisationsdiagnostik eloquenter Hirnareale eine besondere Bedeutung zu. In der vorliegenden Arbeit wird ein Verfahren vorgestellt, daß den präzisen Übertrag der Ergebnisse funktioneller MRT-Studien in die Therapie von Hirntumoren ermöglicht. Desweiteren wird das klinische Potential der fMRT untersucht. In einem hierarchischem System erfolgt die Beurteilung der klinischen Wirksamkeit der Methode zur präoperativen Lokalisationsdiagnostik eloquenter Hirnareale bei Patienten mit Hirntumoren. Methode: Bei 40 Patienten mit supratentoriellen Hirntumoren wurden insgesamt 144 präoperative funktionelle MRT-Studien durchgeführt. Die Bewertung der klinischen Wirksamkeit erfolgte in einem hierarchischem Modell unter Betrachtung der aufgeführten Dimensionen: 1. Ebene: Technische Wirksamkeit 2. Ebene: Wirksamkeit in Bezug auf die diagnostische Genauigkeit 3. Ebene: Wirksamkeit in Bezug auf das diagnostische Denken 4. Ebene: Therapeutische Wirksamkeit 5. Ebene: Wirksamkeit in Bezug auf das Patient-Outcome 6. Ebene: Wirksamkeit in Bezug auf die Gesellschaft Die Ergebnisse der funktionellen MRT-Untersuchungen wurden in ein neurochirurgisches Navigationssystem eingebracht. Intraoperativ besteht für den Operateur die Möglichkeit sich die Lagebeziehung zu den gekennzeichneten Arealen in das Okular des Operationsmikroskop einzuspielen. Ergebnisse: Das geschilderte Verfahren ermöglicht die navigierte Operation von Hirntumoren unter besonderer Berücksichtigung eloquenter- das heißt funktionstragender Hirnareale. Die beschriebene Methode zur Integration der fMRT weist ein hohe Praktikabilität auf. Wie diese Arbeit zeigen konnte, erbringt die fMRT als Methode auch bei Patienten mit Hirntumoren für die klinische Anwendung ausreichend zuverlässige Ergebnisse. Schlussfolgerung: 1. Mit dem geschilderten Verfahren gelingt die zuverlässige Integration von fMRT-Daten in die Therapie von Hirntumoren. 2. Die fMRT ist für den klinischen Einsatz zur präoperativen Lokalisation eloquenter Hirntumoren mit Einschränkungen geeignet.Abstract Introduction: Craniotomy and maximal tumour resection remains the major therapy in patients with brain tumours. Preoperatively it is of great importance to identify eloquent brain areas. In this study we develop a method which allows the precise integration of functional MR-data into the therapy of brain tumours. Additionally we investigated the diagnostic potential of functional MRI in a clinical setting. We were assessing the effectiveness of functional MRI in patients with brain tumours in a hierarchical system. Methods: We performed 122 preoperative, functional MRI studies in 40 patients with supratentorial brain tumours. We evaluated the effectiveness in a hierarchic model. 1. level: technical effectiveness 2. level: diagnostic effectiveness 3. level: diagnostic effectiveness 4. level: therapeutical effectiveness 5. level: patient-outcome 6. level: society The acquired parametric maps were integrated into a neurosurgical navigation system. Intraoperatively the neurosurgeon can have the localisation of functional brain areas displayed within the optical system of the microscope. Conclusion: 1. The described approach allows image guided neurosurgery paying special attention to eloquent brain areas. The method is very practicable and reliable. 2. As we could demonstrate in our work, the functional MRI is sufficiently robust for clinical applicatio
Traitement endovasculaire des anévrysmes intracrâniens non rompus (étude monocentrique concernant 37 patients)
LILLE2-BU Santé-Recherche (593502101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF
Evaluation et optimisation des techniques d'ARM dynamique pour la prise en charge des malformations artério-veineuses intracrâniennes traitées par gamma knife
Grâce aux avancées technologiques réalisées en imagerie, la prise en charge des patients présentant une malformation artério-veineuse (MAV) intracrânienne a bénéficié des méthodes non-invasives d'imagerie des vaisseaux encéphaliques. Ce travail s'est intéressé notamment à l'optimisation des techniques d'angiographie par angiographie RM (ARM) dynamique et à leurs applications cliniques dans le cadre du diagnostic et du traitement des MAV intracrâniennes traitées par radiochirurgie Gamma Knife. Pour caractériser une MAV, trois compartiments distincts doivent être analysés : les afférences artérielles, le nidus malformatif et les veines de drainage. Pour atteindre cet objectif, il est nécessaire de disposer d'une technique d'imagerie présentant une résolution temporelle élevée afin de séparer les différents temps circulatoires et une résolution spatiale élevée afin de visualiser les structures vasculaires de petit diamètre. Dans une étude préliminaire, nous avons optimisé une séquence d'ARM dynamique utilisant des techniques d'imagerie parallèle pour l'étude des vaisseaux intracrâniens. Cette séquence a été évaluée chez dix patients présentant des pathologies neurovasculaires variées. Les résultats ont montré l'intérêt potentiel de cette technique mais la résolution spatiale limitée n'a pas permis de remplacer l'angiographie conventionnelle à la phase diagnostique. Nous avons ensuite amélioré la séquence d'ARM dynamique en appliquant des techniques de lecture partielle du plan de Fourier (technique CENTRA). Cette nouvelle modalité d'imagerie dynamique a fait l'objet d'une étude comparative avec l'angiographie conventionnelle. Les résultats ont montré une excellente concordance entre les deux techniques pour l'étude des afférences, du nidus et du drainage veineux chez 28 patients porteurs d'une MAV intracrânienne non traitée. Enfin, nous avons évalué un algorithme de fusion d'images qui a permis l'intégration des données ARM chez 12 patients présentant une MAV intracrânienne traitée par radiochirurgie Gamma Knife. Chez 10 patients, l'intégration était réalisable avec une très bonne précision spatiale de l'algorithme. En revanche, la comparaison des cibles définies sur la base de données ARM avec l'angiographie conventionnelle montrait une différence significative entre les volumes cibles. L'intégration par fusion d'images d'une séquence d'ARM dynamique utilisant l'imagerie parallèle et différentes techniques de lecture partielle du plan Fourier sera la prochaine étape de nos travaux de recherche clinique dans le cadre du planning radiochirurgical des MAVs traitées par Gamma KnifeLILLE2-BU Santé-Recherche (593502101) / SudocSudocFranceF
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