Turbo gradient-spin-echo (GRASE): first clinical experiences with a fast T2-weighted sequence in MRI of the brain.

The aim of this study was to obtain first clinical experiences with Turbo gradient-spin-echo (TGSE). This fast MRI technique is based on the GRASE sequence which combines the gradient-echo and the spin-echo technique. In 60 patients suffering from different brain pathologies, a T2-weighted TGSE sequence was compared to a conventional spin-echo sequence. Anatomical and pathological structures were evaluated visually by three independent observers; signal and contrast behavior was assessed in regions of interest. TGSE showed reduced signal-to-noise-ratios of anatomical structures except for cerebrospinal fluid. The contrast of tumors, infarctions, and hematomas was similar in both sequence types. Small microangiopathic and inflammatory lesions as well as basal ganglia degeneration presented with diminished contrast in TGSE. The TGSE sequence can already now be used to acquire T2-weighted images in additional orientations requiring extremely short measurement time. However, further improvements of image quality are necessary for routine use of TGSE.