publications by G. Allan Johnson.
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Papers Published
- Johnson, GA; Maki, JH, In vivo measurement of proton diffusion in the presence of coherent motion.,
Invest Radiol, vol. 26 no. 6
(June, 1991),
pp. 540-545 [1650333], [doi] .
(last updated on 2025/02/12)Abstract:
Measurement of the self-diffusion coefficient D of water in tissue has been performed traditionally using the technique proposed by Stejskal and Tanner. A variant of that technique is shown here, employing flow-compensated gradients that significantly reduce the sensitivity to small coherent motions that are common in body imaging. An interleaved sequence with four values of diffusion-sensitizing gradient (b) minimizes registration errors. Eddy currents and other systematic errors are reduced, permitting the measurement of standards in an imaging context within 5% of nonimaging values in the literature. The flow-compensated sequence permits the measure of D for tissues in the abdominal cavity of the rat. We present in vivo measurements of D for the following rat tissues; liver, kidney (cortex), kidney (medulla) muscle, brain, fat.