Clinical evaluation of a speed optimizedT2weighted fast spin echo sequence at 3.0 T using variable flip angle refocusing, half-Fourier acquisition and parallel imaging

Abstract

This paper aims to demonstrate the capabilities of a speed optimized T(2) weighted single-shot turbo spin echo sequence, using parallel imaging, variable flip angle refocusing and half-Fourier acquisition (FAS-TSE), in comparison with a standard TSE (sTSE) sequence in patients with suspected multiple sclerosis (MS). 33 patients presenting with a clinically isolated syndrome (CIS) suggestive of MS were prospectively examined on a 3.0 T MR system using FAS-TSE and a sTSE sequence. The FAS-TSE (scan time 11 s) and the sTSE (scan time 122 s) were compared regarding lesion detectability, lesion contrast, grey/white matter contrast, overall image quality and artefacts. Scanning parameters affecting image contrast and spatial resolution were kept identical. 208 lesions were detected using the sTSE sequence compared with 183 lesions (88%) using the FAS-TSE. The FAS-TSE was rated inferior regarding lesion contrast. The mean value/range/standard deviation of the lesion/white matter contrast were 0.26/0.06-0.49/0.089, respectively, with the sTSE vs 0.21/0.04-0.40/0.081 with the FAS-TSE. The FAS-TSE was rated inferior regarding overall image quality, but superior regarding motion artefacts. The grey/white matter contrast was qualitatively judged as comparable for both sequences. FAS-TSE provides sufficient T2-SE contrast and diagnostic image quality for whole brain studies in 11 s. It is suited to reduce motion artefacts in restless patients and for fast acquisition of additional scanning planes.