Advanced Clinical Cardiovascular MR Imaging and Spectroscopy at 7 Tesla

磁共振成像(MRI)使我们能够非侵入性地对人体内部进行成像。这项技术最初是在大脑中使用的，在过去的5-10年里已经成为临床上用于心脏成像的无价技术。核磁共振扫描仪的磁场强度为1.5特斯拉。增加磁场强度可以提供更高的图像质量，我们已经率先使用了3台特斯拉扫描仪。商业上可用的最高人体磁场强度是7特斯拉，这是我们的下一步。在更高的磁场强度下成像会产生更多的信号，因此，图像获得得更快，或具有更高的空间分辨率。我们将开发的领域是那些受到1.5特斯拉和3特斯拉低信噪比(SNR)限制的领域。这些包括对冠状动脉和人体心脏中富含能量的代谢物进行成像。冠状动脉成像很重要，因为这些血管是心脏供血的关键(堵塞导致心脏病发作？)。7T的高信噪比将使我们能够以比MRI更高的分辨率成像这些血管的血液和管壁，使我们能够可视化小斑块和微小的损伤。心脏的代谢状况是我们牛津大学处于世界领先地位的另一个重要研究领域。一种名为MRS(磁共振波谱)的技术显示了心脏的生物化学。磷酸肌酸和三磷酸腺苷是提供能量的重要代谢物，即使在功能变化明显之前，它们的水平也可以给出损害的迹象。在7T时，较高的空间分辨率可以对心脏的小区域进行MRS检查，相当于目前临床检查所需的MRS检查(在低场强下这是不可能的)。其他项目将建立在这些方法的基础上，以观察氧气供应、纤维疤痕组织的程度以及心脏小血管的血液供应。在临床上，这些发展有可能将心脏代谢、氧合和冠状动脉斑块生物学的磁共振成像从一种利基研究工具转变为一种主流诊断手段，可以将患者作为个体对待，使医生能够随着时间的推移监测疾病的进展或对治疗的反应。这些技术将大大有助于改善心血管健康和减轻心血管疾病的负担。我们的计划非常新颖，我们将成为英国第一个，可能也是欧洲第一个在7T开发心脏磁共振的地点。

Magnetic Resonance Imaging (MRI) allows us to image the inside of the human body non-invasively. Pioneered in the brain this technique has become invaluable over the last 5-10 years for imaging the heart in the clinic. MRI scanners operate at a magnetic field strength of 1.5 Tesla. Increasing the magnetic field strength can provide higher image quality and we have pioneered the use of 3 Tesla scanners. The highest commercially available human field strength is 7 Tesla, which is our next step.Imaging at higher field strength results in more signal, and thus, the images are obtained quicker, or with higher spatial resolution. The areas that we will develop are those that are limited by low SNR (signal-to-noise ratio) at 1.5 and 3 Tesla. These include imaging the coronary arteries and the energy-rich metabolites in the human heart. Coronary artery imaging is important as these vessels are critical to supplying blood to the heart (blockages cause ?heart attack?). The higher SNR of 7T will allow us to image the blood and walls of these vessels at higher resolution than has previously been possible with MRI enabling us to visualise small plaques and subtle damage. The metabolic condition of the heart is another important area of research where we in Oxford are world leaders. A technique called MRS (magnetic resonance spectroscopy) shows the biochemistry of the heart. Levels of phosphocreatine and adenosine triphosphate, which are essential energy-providing metabolites, can give an indication of damage even before functional changes become apparent. At 7T, the higher spatial resolution enables the MRS examination of small regions in the heart, equivalent to those presently required in clinical examination (this is impossible at lower field). Additional projects will build on these methods to look at oxygen supply, the degree of fibrous scar tissue, and the blood supply from small vessels in the heart. Clinically these developments have the potential to transform MR imaging of cardiac metabolism, oxygenation, and coronary plaque biology from a niche research tool into a mainstream diagnostic measure that can treat the patient as an individual, enabling doctors to monitor the progress of a disease or the response to therapy over time. These techniques would contribute significantly to improving cardiovascular health and to relieving the burden of cardiovascular disease. Our plans are highly novel, and we would be the first site in the UK, and probably in Europe, developing cardiac MR at 7T.