HIGH RESOLUTION INTERACTIVE CORONARY ARTERY MRA

描述（改编自申请人摘要）：申请人提出， 应用快速MR成像脉冲序列和实时信号处理 高分辨率磁共振成像技术的发展， 冠状动脉 具体假设是，1 mm各向同性 可以可靠地确定天然冠状动脉树的图像的分辨率 人类在一次或有限次数的屏气期间获得的。 目前的冠状动脉MRA技术受到以下因素的限制， 包括：大量所需相位编码视图、有限的SNR 由于心脏和心脏运动引起的不清晰， 血液与背景的对比度 这些都变得更加严重，因为决议是 提高 申请人建议在本申请中解决这些限制。 项目：1. 心脏MR透视。 近实时心脏成像 将用于交互式地识别目标冠状动脉血管， 定位所需的倾斜成像平面或板，并提供即时 切换到高分辨率血管造影序列。 一个或多个这样的 将为三个主要冠状动脉中的每一个识别厚片， 从而能够形成每个的“选择性”血管造影照片。 实时 屏气反馈将提供可再现的，但允许灵活的 屏住呼吸; 2. 高分辨率磁化制备梯度回波MR 动脉造影 反转恢复磁化制备梯度回波 序列将适用于冠状动脉造影成像。 归零 背景心肌将使小的分支和更远端的脉管系统 比当前技术更好地观察。 双斜位采集 将允许所需的相位编码数量的显著减少 从而减少扫描时间，允许仅在几个 屏住呼吸 反转板将被定制，以避免饱和 动脉血;和3. 高分辨率多激发回波平面MR 动脉造影 2-D和3-D多激发EPI技术将适用于 冠状动脉造影 每个心动周期的拍摄次数、 镜头和梯度矩归零的程度将被优化， 血管造影成像 EPI技术预计将提供更多的 与当前方法相比，单位时间内的视图数（> 3倍）， 完整冠状动脉树的单次屏气成像。 的 申请人预计，该项目开发的技术可以形成 最终的交互系统的起点， 心脏成像检查的要素。

DESCRIPTION (Adapted from Applicant's Abstract): The applicants proposed to apply fast MR imaging pulse sequences and real-time signal processing techniques in developing techniques for high resolution MR imaging of the coronary arteries. The specific hypothesis is that 1 mm isotropic resolution of images of the native coronary arterial tree can be reliably obtained in humans during a single or limited number of breathholds. Current techniques for coronary artery MRA are limited from factors which include: a large number of required phase encoding views, limited SNR, unsharpness due to cardiac and respiratory-induced motion, and limited blood-to-background contrast. These all become more severe as resolution is improved. The applicants proposed to address these limitations in the projects of: 1. Cardiac MR Fluoroscopy. Near real-time cardiac imaging will be used to interactively identify the targeted coronary artery vessels, position the desired oblique imaging plane or slab, and provide instant switching to a high resolution angiographic sequence. One or more such slabs will be identified for each of the three major coronary arteries, enabling formation of a "selective" angiogram for each. Real-time breathhold feedback will provide reproducible and yet allow flexible breathholding; 2. High Resolution Magnetization-Prepared Gradient Echo MR Angiography. An inversion recovery magnetization-prepared gradient echo sequence will be adapted for coronary angiographic imaging. Nulling of background myocardium will enable small branches and more distal vasculature to be better seen than with current techniques. Double oblique acquisition will allow considerable reduction of the required number of phase encodings and thus scan time reduction, allowing acquisition over only several breathholds. The inversion slab will be tailored to avoid saturation of arterial blood; and 3. High Resolution Multi-Shot Echo-Planar MR Angiography. 2-D and 3-D multi-shot EPI techniques will be adapted for coronary angiography. The number of shots per cardiac cycle, views per shot, and degree of gradient moment nulling will be optimized for angiographic imaging. EPI techniques are expected to provide an increased (>3X) number of views per unit time compared to current methods and enable single breathhold imaging of a complete coronary artery tree. The applicants projected that the techniques developed in this project can form the starting point for an eventual interactive system for performing many elements of a cardiac imaging examination.