Comparison of spin-echo MR pulse sequences for imaging of the brain.

PURPOSE To determine the value of the gradient- and spin-echo (GRASE) technique as compared with the fast spin-echo and conventional spin-echo techniques in MR imaging of the brain. METHODS Sixty-six patients with ischemic and neoplastic brain lesions were examined with T2-weighted spin-echo, fast spin-echo, and GRASE sequences. Three independent observers evaluated the contrast characteristics of anatomic and pathologic structures and of artifacts. Quantitative image analysis included region-of-interest measurements of anatomic structures and lesions. RESULTS The contrast of anatomic structures was superior in images obtained with conventional and fast spin-echo techniques as compared with those obtained with the GRASE technique. Extended lesions, such as tumors and territorial infarcts, were identified equally with all techniques. For delineation of small ischemic lesions, GRASE was slightly inferior to fast and conventional spin-echo sequences. Flow artifacts were considerably reduced with fast spin-echo and GRASE sequences. Chemical-shift artifacts were significantly reduced, but ringing artifacts were more pronounced with GRASE. CONCLUSION Fast spin-echo remains the standard technique in MR imaging of the brain. However, GRASE might be useful in special cases, such as with uncooperative patients whose conventional or fast spin-echo images show severe motion artifacts.