Imaging of the brain using the fast-spin-echo and gradient-spin-echo techniques

Abstract

The aim of our study was to compare gradient-spin-echo (GRASE) to fast-spin-echo (FSE) sequences for fast T2-weighted MR imaging of the brain. Thirty-one patients with high-signal-intensity lesions on T2-weighted images were examined on a 1.5-T MR system. The FSE and GRASE sequences with identical sequence parameters were obtained and compared side by side. Image assessment criteria included lesion conspicuity, contrast between different types of normal tissue, and image artifacts. In addition, signal-to-noise, contrast-to-noise, and contrast ratios and were determined. The FSE technique demonstrated more lesions than GRASE and with generally better conspicuity. Smaller lesions in particular were better demonstrated on FSE because of lower image noise and slightly weaker image artifacts. Gray-white differentiation was better on FSE. Ferritin and hemosiderin depositions appeared darker on GRASE, which resulted in better contrast. Fatty tissue was less bright on GRASE. With current standard hardware equipment, the FSE technique seems preferable to GRASE for fast T2-weighted routine MR imaging of the brain. For the assessment of hemosiderin or ferritin depositions, GRASE might be considered.

Rapid whole cerebrum myelin water imaging using a 3D GRASE sequence

“…By acquiring multiple gradient echoes per refocusing pulse on either side of the spin echo, an accelerated acquisition trajectory may be realized which exhibits pure T 2 weighting in the k-space centre (spin echo signal) and T 2 ⁎ weighting in the k-space periphery (gradient echo signal). Some researchers reported that GRASE was less effective in the detection of small or hypointense lesions (Patel et al, 1995;Umek et al, 1998), and produced images with lower signal to noise ratio (SNR) and less pronounced contrast (Fellner et al, 1995(Fellner et al, , 1997. However, others found that GRASE showed better detection of lesions, especially those with low signal (Melhelm et al, 1998) or those which exhibited paramagnetic susceptibility characteristics (Rockwell et al, 1997).…”

“…A combined gradient and spin echo sequence known as gradient and spin echo (GRASE) (Feinberg and Oshio, 1991) has previously been used to accelerate clinical MR acquisitions (Fellner et al, 1995(Fellner et al, , 1997Melhelm et al, 1998;Patel et al, 1995;Rockwell et al, 1997;Umek et al, 1998). By acquiring multiple gradient echoes per refocusing pulse on either side of the spin echo, an accelerated acquisition trajectory may be realized which exhibits pure T 2 weighting in the k-space centre (spin echo signal) and T 2 ⁎ weighting in the k-space periphery (gradient echo signal).…”

7T MRI‐Histologic Correlation Study of Low Specific Absorption Rate T2‐Weighted GRASE Sequences in the Detection of White Matter Involvement in Multiple Sclerosis

“…At lower magnetic strength, GRASE imaging was shown to reduce scan time for brain imaging and to have potential for clinical use in patients with brain disorders …”

MR imaging: acronyms and clinical applications

“…Recent reports comparing the performance of TSE and GRASE are slightly discouraging, claiming that TSE is more consistent in image quality, showing fewer artifacts [177]. Recent reports comparing the performance of TSE and GRASE are slightly discouraging, claiming that TSE is more consistent in image quality, showing fewer artifacts [177].…”