Quantitative Evaluation of the Exchange Time and T2 Associated with an Inhomogeneous Component Using Inhomogeneous Magnetization Transfer Imaging

Gopal Varma¹, Fotini Kourtelidis¹, David C. Alsop¹

Application of quantitative magnetization transfer (MT) to white matter in the brain is of interest, particularly in studies of degenerative diseases. A greater contrast and sensitivity has been shown from inhomogeneous MT (IHMT) imaging. A more quantitative analysis of the IHMT effect is applied in hair conditioner phantoms and in vivo based on a 2 pool model to elucidate exchange time and T₂ parameters associated with an inhomogeneous component. An exchange time of ~6ms and T₂ of ~200&[micro]s is found in healthy volunteers, which are distinct from the results in vitro.