Rapid and accurate measurement of transverse relaxation times using a single shot multi-echo echo-planar imaging sequence.

Journal article

Methods for making rapid and accurate measurements and maps of the transverse relaxation time from a single free induction decay (FID) are proposed. The methods use a multi-echo sequence in combination with B1 insensitive (hyperbolic secant or BIREF2b) refocusing pulses and rapid echo-planar imaging techniques. The results were calibrated against a single spin echo echo-planar imaging sequence using a phantom containing a range of CuSO4 concentrations. The mean percentage absolute difference between the multi-echo and single-echo results was 3% for the multi-echo sequence using the hyperbolic secant refocusing pulse, and 7% for the multi-echo sequence using the BIREF2b refocusing pulse, compared to 13% for a multi-echo sequence using a nonselective sinc refocusing pulse. The use of the sequences in vivo has been demonstrated in studies of gastric function, i.e., the measurement of gastric dilution and monitoring of formation of a raft of alginate polysaccharide within the stomach.

Authors: Tyler, D; Moore, R; Marciani, L; Gowland, P

• Publication status: Published
• Journal: Magnetic resonance imaging
• Volume: 22
• Issue: 7
• Pages: 1031-1037
• Publication date: 2004-09-01
• DOI: 10.1016/j.mri.2004.01.069
• EISSN: 1873-5894
• ISSN: 0730-725X
• Language: English
• Keywords: Antacids; Alginates; Aluminum Hydroxide; Phantoms, Imaging; Copper Sulfate; Drug Combinations; Sodium Bicarbonate; Silicic Acid; Echo-Planar Imaging; Polysaccharides; Humans; Gastrointestinal Transit