A new steady‐state imaging sequence for simultaneous acquisition of two MR images with clearly different contrasts

Abstract

We present a new steady-state imaging sequence, which simultaneously allows in a single acquisition the formation of two MR images with clearly different contrasts. The contrast of the first image is FISP-like, whereas the second image is strongly T2-weighted. In principle the T2 values in the image can be calculated from the combination of the first and second images. We also show calculated T2 images.

The morphology of articular cartilage assessed by magnetic resonance imaging (MRI)

“…DESS (dual echo at steady state), which combines a FISP-like image with the strong T2-contrast of a second echo [4], has been advocated to bring about an even sharper contrast between articular cartilage and synovial fluid than MTC [29]. Our results suggest that DESS is as adequate for the delineation of the cartilage volume as the MTC-FISP sequence.…”

Rapid estimation of cartilage T2 based on double echo at steady state (DESS) with 3 Tesla

“…2a). In the DESS sequence, these two signals are combined to further enhance the T2 contrast, but it is also possible to use these signals to obtain information about the spin-spin relaxation time constant, T2 (12) (Fig. 1d).…”

“…Perhaps the most widely used quantitative MR tissue parameter applied to cartilage imaging is T2 (11). Based on the theory of Bruder et al (12), the simultaneous acquisition of two separate, steady-state, free precession (SSFP) echoes allows the formation of two MR images with clearly different contrasts: S ϩ ϭ FISP (fast imaging steady precession); and S Ϫ ϭ PSIF (reversed FISP). The DESS sequence combines these signals into one by the calculation of the sum of squares of both echoes.…”

3D Double-Echo Steady-State with Water Excitation MR Imaging of the Intraparotid Facial Nerve at 1.5T: A Pilot Study

“…PSIF signal intensity accentuates the signal intensity of the components with long T2s, such as CSF; FISP signal intensity provides more anatomic details with a contrast dominated by the T1/T2 ratio. [12][13][14]20 The WE technique has been recommended in combination with SSFPtype sequences for orthopedic and cine cardiovascular imaging. 10,11,21 With this technique, only water is excited by using section-selective composite pulses, while lipid spins are left in equilibrium, providing advantages of no disruption of the steady-state and uniform fat suppression.…”