Multiple Sclerosis, 1 June 2003, vol. 9, no. 3, pp. 246-249(4)
Davies G.R.; Ramani A.; Dalton C.M.; Tozer D.J.; Wheeler-Kingshott C.A.M.; Barker G.J.; Thompson A.J.; Miller D.H.; Tofts P.S.
 NMR Research Unit, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
We report on a new quantitative magnetization transfer (MT) technique that allows for the in vivo estimation of the macromolecular proton fraction (f) and the bound pool T2 relaxation time (T2b), whilst permitting whole brain coverage.
In this pilot study, five subjects with multiple sclerosis (MS) and five healthy controls were studied.
Both f and T2b were significantly different between MS lesions and normal control white matter (WM).
Relationships between f and T1 relaxation time (Spearman's rank correlation coefficient (rs)= -0.97, P<0.001) and f and the magnetization transfer ratio (MTR; rs=0.80, P<0.001) were observed.
Compared with MTR, f and T2b have the potential advantage of relative independence from MT acquisition protocol while offering more pathologically specific information.
In particular, f may provide a more direct indication of myelin content in WM.