Neurovascular Non Contrast-Enhanced MR Angiography at 3T (NCE MRA)
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
研究概览
地位
详细说明
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.
研究类型
注册 (实际的)
联系人和位置
学习地点
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Brittany
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Rennes、Brittany、法国、35033
- Rennes University Hospital
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参与标准
资格标准
适合学习的年龄
接受健康志愿者
有资格学习的性别
取样方法
研究人群
描述
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
学习计划
研究是如何设计的？
设计细节
队列和干预
团体/队列 |
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arteriovenous malformations
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Arterial stenosis
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Post-treatment follow-up
Patient with an arteriovenous malformation for which treatment by embolization or radiosurgery is indicated
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研究衡量的是什么？
主要结果指标
结果测量 |
措施说明 |
大体时间 |
|---|---|---|
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A reading grid assessing the image quality
大体时间：54 months
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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
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次要结果测量
结果测量 |
措施说明 |
大体时间 |
|---|---|---|
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An evaluation grid classifying the main pathological findings
大体时间：54 months
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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
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An evaluation of the performance of new sequences
大体时间：54 months
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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.
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54 months
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合作者和调查者
调查人员
- 首席研究员：jean-yves gauvrit、Rennes University Hospital
研究记录日期
研究主要日期
学习开始 (实际的)
初级完成 (实际的)
研究完成 (实际的)
研究注册日期
首次提交
首先提交符合 QC 标准的
首次发布 (估计)
研究记录更新
最后更新发布 (实际的)
上次提交的符合 QC 标准的更新
最后验证
更多信息
与本研究相关的术语
其他研究编号
- 2011-A01258-33
- LOC/11-19 (其他标识符：Rennes University Hospital)
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