Diffusion of myelin water.

Andrews, Trevor J.; Osborne, Michael T.; Does, Mark D.

We studied compartmentally specific characteristics of water diffusion in excised frog sciatic nerve by combining T1 or T2 selective acquisitions with pulse-gradient spin-echo (PGSE) diffusion weighting, with the specific objective of characterizing myelin water diffusion. Combining a PGSE with a Carr-Purcell-Meiboom-Gill (CPMG) acquisition provided apparent diffusion coefficients (ADCs) for each of the three T2 components found in nerve, including the short-lived component believed to be derived from myelin water. Double-inversion-recovery (DIR) preparation provided an alternate means of discriminating myelin water, and in combination with PGSE provided somewhat different measures of ADC. The DIR measures yielded myelin water ADCs of 0.37 μm2/ms (parallel to nerve) and 0.13 μm2/ms (perpendicular to nerve). These ADC estimates were postulated to be more accurate than those based on T2 discrimination, although the difference between the two findings is not clear. Magn Reson Med, 2006. © 2006 Wiley-Liss, Inc.

Magnetic Resonance in Medicine, 2006, Vol 56, Issue 2, p381

0740-3194

Academic Journal

10.1002/mrm.20945