HIGH-SPEED MRI TUMOR IMAGING

提出了一种腹部和胸部肿瘤成像系统。虽然 磁共振成像提供了极好的软组织对比度，无创无毒 时尚，收益主要积累在那些可以 成功地固定了。因此，头部、骨盆、脊柱、四肢等。 可以稳定扫描几分钟。腹部和胸部的影像 都被严重的呼吸制品所困扰。我们建议提供这些服务 通过获取数据对腹部和胸部的所有区域都有好处 在屏息间隔内。这是通过一种新的系统实现的 利用一组交错的k空间正方形螺旋扫描。这个独一无二的 方法，该方法已成功实现，在 使用传统的核磁共振成像系统只需几秒钟。 拟议的快速成像系统将得到增强，配备了一些 重要特征。肿瘤通常很难观察到，因为它们 其特征与周围组织相似。对比是 通过使用非常晚的回声显著改善，但存在过度 噪音。这些图像可以使用一种 “相关”滤波法，使用低噪声早期回波来增强 高对比度的后期回波图像。改进版的其他重要功能 肿瘤图像包括肿瘤血管的血流成像、稳健的分离 水和脂肪，以及自聚焦激发，使成像 具有极短松弛时间的材料。肺等组织 通常不能被可视化的实质可以用这个来成像 接近。

A system of tumor imaging of the abdomen and thorax is proposed. Although MRI has provided excellent soft tissue contrast in a non-invasive non-toxic fashion, the benefits have accrued primarily in those areas which can be successfully immobilized. Thus the head, pelvis, spine, extremities etc. can be stabilized for a few minute scan. Images of the abdomen and thorax are plagued by severe breathing artifacts. We propose to provide these benefits to all areas of the abdomen and thorax by acquiring the data within a breath-holding interval. This is accomplished by a novel system utilizing a set of interleaved square spiral scans of k-space. This unique approach, which has been successfully implemented, acquires the data in a few seconds using conventional MRI imaging systems. The proposed fast imaging system will be enhanced with a number of important features. Tumors are often difficult to visualize because their characteristics are similar to surrounding tissue. The contrast is significantly improving by using very late echoes, but suffer from excess noise. The images can be profoundly improved using a system of "correlative" filtering where a low-noise early echo is used to enhance the high-contrast late echo image. Other important features of the improved tumor images include flow imaging for tumor vascularity, robust separation of water and fat, and self-focusing excitations which enable the imaging of materials with extremely short relaxation times. Tissues such as lung parenchyma, which is normally not visualized, can be imaged with this approach.