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Neurovascular Non Contrast-Enhanced MR Angiography at 3T (NCE MRA)

13 aprile 2018 aggiornato da: Rennes University Hospital

Morphological and Dynamic Non Contrast-enhanced MR Angiography in the Exploration of Neurovascular Diseases

MR angiography (MRA) has become essential in the treatment of neurovascular diseases, including ischemic stroke - the first cause of disability in occidental countries, vascular malformations such as aneurysms, arteriovenous fistulas and malformations, whose treatments are improving year after year.

MRA is an alternative to digital substracted angiography (DSA), circumventing th use of endovascular catheterism, irradiation and injection of iodinated contrast agent. Contrast-Enhanced MRA (CE-MRA) with gadolinium injection is currently the reference standard for vascular MR exploration but still presents many limitations inherent to the injection of contrast medium. Hence, the synchronization of the acquisition with bolus contrast injection limits the improvement of spatial and temporal resolutions and requires an accurate synchronization of the acquisition with the arrival of the bolus.

Moreover, the acquisition can be repeated as required as it does not require any contrast injection.

Besides, the increase in nephrogenic systematic fibrosis clinical cases, which would be secondary to gadolinium chelates injection, in patients with chronic renal insufficiency has restricted the use of CE-MRA. More than 500 cases were described to date in the world.

Its occurrence is currently estimated around 4 % for patients in terminal chronic renal insufficiency and its mortality around 30 %.

According to the recommendations of AFSSAPS from August, 2007, two gadolinium contrast agent (Gadodiamide-OMNISCAN *, General Electric HealthCare and Gadopentetate Dimeglumine-MAGNEVIST *, Bayer HealthCare) are contraindicated if the glomerular filtration rate is lower than 30 ml/mn.

Non-contrast enhanced MR angiography (NCE MRA) techniques have been proposed to provide complete and non-invasive investigation of the vasculature, thus offering patients with chronic renal insufficiency, as well as pregnant or nursing women a surrogate with no side effects.

Moreover, the use of high field (3T) MR imaging offers improved signal to noise ratio. Combined with the use of phased array coils and parallel imaging, new NCE MRA sequences can achieve juxta-millimeter isotropic spatial resolution and temporal resolution of about 50 ms close to those of cerebral DSA.

These sequences allow a joint hemodynamical and morphological assessment of lesions, both at the cervical and cerebral levels, whether at diagnosis or during patient follow-up

Panoramica dello studio

Stato

Completato

Descrizione dettagliata

The main objective is to evaluate the quality of the NCE images obtained in the exploration of neurovascular diseases, at the cervical and cerebral levels.

Secondary objectives are:

  • to compare the NCE MRA sequences with the CE MRA sequences used in the clinical routine.
  • to evaluate the anatomic and hemodynamic changes observable with sequences in the follow-up of patients, particularly those treated with partial embolization or radiosurgery.

By circumventing the limitation to short bolus duration synchronization, the new dynamic sequences have the potential to achieve higher temporal resolution without compromising spatial resolution. Arteries and arteriovenous shunts may be more precisely identified and, due to a better visibility of small vessels allow a more accurate dynamic analysis.

Finally, the sequence being derived from arterial spin labeling, and differing from time of flight or phase contrast sequences, should allow for an exploration less dependent on the vascular geometry with better anatomical analysis. For example, the tendency to overestimate arterial stenoses could be reduced.

The robustness of sequences allow the non-invasive monitoring of patients including it possible to monitor the hemodynamic changes after radiosurgery or embolization.

Tipo di studio

Osservativo

Iscrizione (Effettivo)

80

Contatti e Sedi

Questa sezione fornisce i recapiti di coloro che conducono lo studio e informazioni su dove viene condotto lo studio.

Luoghi di studio

    • Brittany
      • Rennes, Brittany, Francia, 35033
        • Rennes University Hospital

Criteri di partecipazione

I ricercatori cercano persone che corrispondano a una certa descrizione, chiamata criteri di ammissibilità. Alcuni esempi di questi criteri sono le condizioni generali di salute di una persona o trattamenti precedenti.

Criteri di ammissibilità

Età idonea allo studio

18 anni e precedenti (Adulto, Adulto più anziano)

Accetta volontari sani

No

Sessi ammissibili allo studio

Tutto

Metodo di campionamento

Campione non probabilistico

Popolazione di studio

Patients with neurovascular diseases

Descrizione

Inclusion Criteria:

  • Men and women over 18 years
  • Any adult patient known or clinically suspect to present a neurovascular disease (arterial stenosis ou arteriovenous malformations), the assessment of which requires an MRA or patient having an arteriovenous malformation for which treatment by embolization or radiosurgery is indicated multidisciplinary meeting and followed in the ordinary course of this treatment
  • Patient able of accepting protocol information
  • Patient who received information about the protocol and had not expressed its opposition to participate

Exclusion Criteria:

  • A contraindication to MRI, in particular pacemakers or implantable defibrillators, cochlear implants, neurosurgical clips, intra-orbital or brain metallic foreign bodies, endo prothesis since less than 4 weeks or osteosynthesis material since less than 6 weeks
  • Contraindication to the injection of contrast agent: pregnancy, lactation, history of allergic reaction to contrast agent injection
  • Hemodynamically unstability, acute respiratory failure, a precarious condition or a need for continuous monitoring incompatible with the constraints of MR imaging
  • Patient with severe kidney with Glomerular Filtration rate < 30 ml/min
  • Persons subject to major legal protection (safeguarding justice, guardianship, trusteeship), persons deprived of liberty

Piano di studio

Questa sezione fornisce i dettagli del piano di studio, compreso il modo in cui lo studio è progettato e ciò che lo studio sta misurando.

Come è strutturato lo studio?

Dettagli di progettazione

Coorti e interventi

Gruppo / Coorte
arteriovenous malformations
Arterial stenosis
Post-treatment follow-up
Patient with an arteriovenous malformation for which treatment by embolization or radiosurgery is indicated

Cosa sta misurando lo studio?

Misure di risultato primarie

Misura del risultato
Misura Descrizione
Lasso di tempo
A reading grid assessing the image quality
Lasso di tempo: 54 months

Qualitative and quantitative evaluation of image quality :

This analysis will be performed using a reading grid assessing the image quality (signal to noise ratio, motion artefacts, artefacts other than motion) and identifying the vessels visualized

54 months

Misure di risultato secondarie

Misura del risultato
Misura Descrizione
Lasso di tempo
An evaluation grid classifying the main pathological findings
Lasso di tempo: 54 months

Assessment of diagnosis performance of the nem NCE MRA sequences :

This assessment will be performed using an evaluation grid classifying the main pathological findings, ie arterial stenosis or arteriovenous shunts and assessing their extent

54 months
An evaluation of the performance of new sequences
Lasso di tempo: 54 months
Evaluation of the performance of new sequences to quantify hemodynamic parameters in arteriovenous shunts and detect anatomical and hemodynamic changes after treatment with partial embolization or radiosurgery.
54 months

Collaboratori e investigatori

Qui è dove troverai le persone e le organizzazioni coinvolte in questo studio.

Investigatori

  • Investigatore principale: jean-yves gauvrit, Rennes University Hospital

Studiare le date dei record

Queste date tengono traccia dell'avanzamento della registrazione dello studio e dell'invio dei risultati di sintesi a ClinicalTrials.gov. I record degli studi e i risultati riportati vengono esaminati dalla National Library of Medicine (NLM) per assicurarsi che soddisfino specifici standard di controllo della qualità prima di essere pubblicati sul sito Web pubblico.

Studia le date principali

Inizio studio (Effettivo)

5 giugno 2012

Completamento primario (Effettivo)

22 novembre 2016

Completamento dello studio (Effettivo)

22 novembre 2016

Date di iscrizione allo studio

Primo inviato

23 marzo 2012

Primo inviato che soddisfa i criteri di controllo qualità

27 marzo 2012

Primo Inserito (Stima)

29 marzo 2012

Aggiornamenti dei record di studio

Ultimo aggiornamento pubblicato (Effettivo)

17 aprile 2018

Ultimo aggiornamento inviato che soddisfa i criteri QC

13 aprile 2018

Ultimo verificato

1 aprile 2018

Maggiori informazioni

Termini relativi a questo studio

Altri numeri di identificazione dello studio

  • 2011-A01258-33
  • LOC/11-19 (Altro identificatore: Rennes University Hospital)

Queste informazioni sono state recuperate direttamente dal sito web clinicaltrials.gov senza alcuna modifica. In caso di richieste di modifica, rimozione o aggiornamento dei dettagli dello studio, contattare register@clinicaltrials.gov. Non appena verrà implementata una modifica su clinicaltrials.gov, questa verrà aggiornata automaticamente anche sul nostro sito web .

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