Abstract
The acquisition time of common fast imaging techniques is limited by the switching times of the magnetic field gradients necessary to encode the RF signal for the spatial coordinates. We introduce a method by which multiple spin echoes are generated using a burst of short RF pulses. Spatial encoding can be introduced into the echotrain using very few gradient switching steps. Acquisition times as short as 40 ms for a 64 × 128 image matrix can thus be achieved on a whole body system using a conventional gradient system with a gradient amplitude of 10 mT/m and 1 ms switching time. Different possibilities to introduce slice selection into the basically non-slice selective experiment are presented which also allow to manipulate the image contrast. Quantitative measurements of T1- and T2-relaxation rates as well as diffusion and perfusion constants can thus be performed within a few seconds.
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