Li Zhiqiang, Wang Dinghui, Robison Ryan K, Zwart Nicholas R, Schär Michael, Karis John P, Pipe James G
Imaging Research, Barrow Neurological Institute, Phoenix, Arizona, USA.
Philips Healthcare, Cleveland, Ohio, USA.
Magn Reson Med. 2016 Feb;75(2):729-38. doi: 10.1002/mrm.25660. Epub 2015 Mar 7.
T2 -weighted imaging is of great diagnostic value in neuroimaging. Three-dimensional (3D) Cartesian turbo spin echo (TSE) scans provide high signal-to-noise ratio (SNR) and contiguous slice coverage. The purpose of this preliminary work is to implement a novel 3D spiral TSE technique with image quality comparable to 2D/3D Cartesian TSE.
The proposed technique uses multislab 3D TSE imaging. To mitigate the slice boundary artifacts, a sliding-slab method is extended to spiral imaging. A spiral-in/out readout is adopted to minimize the artifacts that may be present with the conventional spiral-out readout. Phase errors induced by B0 eddy currents are measured and compensated to allow for the combination of the spiral-in and spiral-out images. A nonuniform slice encoding scheme is used to reduce the truncation artifacts while preserving the SNR performance.
Preliminary results show that each of the individual measures contributes to the overall performance, and the image quality of the results obtained with the proposed technique is, in general, comparable to that of 2D or 3D Cartesian TSE.
3D sliding-slab TSE with a spiral-in/out readout provides good-quality T2 -weighted images, and, therefore, may become a promising alternative to Cartesian TSE.
T2加权成像在神经成像中具有重要的诊断价值。三维(3D)笛卡尔快速自旋回波(TSE)扫描提供了高信噪比(SNR)和连续的层面覆盖。这项初步工作的目的是实现一种新型的3D螺旋TSE技术,其图像质量可与2D/3D笛卡尔TSE相媲美。
所提出的技术采用多层面3D TSE成像。为了减轻层面边界伪影,将滑动层面方法扩展到螺旋成像。采用螺旋进/出读出方式,以尽量减少传统螺旋出读出方式可能出现的伪影。测量并补偿由B0涡流引起的相位误差,以便将螺旋进和螺旋出图像进行合并。使用非均匀层面编码方案来减少截断伪影,同时保持SNR性能。
初步结果表明,各项单独的措施都对整体性能有贡献,并且所提出的技术所获得的结果的图像质量总体上可与2D或3D笛卡尔TSE相媲美。
采用螺旋进/出读出方式的3D滑动层面TSE可提供高质量的T2加权图像,因此可能成为笛卡尔TSE的一种有前景的替代方法。