3D-CE-MRA with High-Resoluton Extended Acquisition

描述（由申请人提供）：外周磁共振血管造影 (MRA)受限于需要使用有限的 造影剂的量。“药团追踪”技术成像几个 一次缓慢的注射后。最近的报告显示， 由于可用的时间有限，该技术提供有限的空间分辨率 在每个车站。最佳采集时机是困难的，由于潜在的 在同一视场内的对比度到达时间的变化。最后， 静脉污染在下肢中是常见的。 我们正在开发新的高分辨率，稀疏采样投影 收购。将体积覆盖范围、空间分辨率和速度结合在一起， 单一质量测量，这些时间分辨序列的性能好4-13倍 比我们以前报告的笛卡尔，时间分辨技术（3D TRICKS）。 这些序列将针对外周血管造影进行优化。时间分辨 信息消除了腹部站以下的定时考虑， 降低了对容器之间填充延迟的敏感性。我们建议使用 延长扫描时间和血管内造影剂以增加SNR。 这将需要静脉抑制，这将是基于空间和 体素相对于参考动脉和静脉的时间相关性 感兴趣的区域。单独后扩展时间分辨成像 在几个成像站的注射可以同时增加覆盖范围， 空间分辨率和SNR。 序列和静脉抑制方法将在Specific Aim I中进行优化 使用模拟、幻影和猪。在《特定目标2》中， 延迟血管充盈和抑制静脉在猪模型中使用 血管内药物MS-325将使用DSA进行验证。在具体目标3中， 志愿者和患者将在一个工作站接受全剂量的 传统的对比。将测量T1以开发模拟T1的注射。 1/3剂量MS-325的T1。术中X线血管造影将用于 患者MRA研究的验证所提出的技术具有类似的 在MRA的其他领域的潜力。

DESCRIPTION (Provided by Applicant): Peripheral magnetic resonance angiography (MRA) is limited by the need to cover a large field of view using a limited amount of contrast material. The "bolus chase" technique images several stations following a single slow injection. Recent reports indicate that this technique provides limited spatial resolution due to the limited time available at each station. Optimal acquisition timing is difficult due to potential variations in contrast arrival times within the same field of view. Finally, venous contamination is common in the lower extremities. We are developing novel high resolution, sparsely sampled projection acquisitions. Combining volume coverage, spatial resolution and speed into a single quality measure, these time-resolved sequences perform 4-13 times better than our previously reported Cartesian, time-resolved technique (3D TRICKS). These sequences will be optimized for peripheral angiography. Time-resolved information eliminates timing considerations below the abdominal station while reducing sensitivity to filling delays between vessels. We propose to use extended scanning times and intra-vascular contrast material to increase SNR. This will require vein suppression that will be based on the spatial and temporal correlation of voxels relative to reference arterial and venous regions of interest. Extended time-resolved imaging following separate injections at several imaging stations can simultaneously increase coverage, spatial resolution and SNR. The sequences and vein suppression method will be optimized in Specific Aim I using simulations, phantoms and pigs. In Specific Aim 2, the ability to image delayed vessel filling and to suppress veins in a pig model using an intra-vascular agent, MS-325, will be validated using DSA. In Specific Aim 3, volunteers and patients will be imaged at one station with full doses of conventional contrast. Tl will be measured to develop injections that mimic the Tl from 1/3 dose MS-325. Intra-operative X-ray angiography will be used for validation of the patient MRA studies The proposed techniques have similar potential in other areas of MRA.