Bias in the apparent exchange rate measurements: insight from numerical simulations

Using double diffusion encoding it is possible to acquire microstructural and water exchange information. Here, simulations are used to study how restriction effects influence apparent exchange measurements. The simulations indicate that at the chosen experimental parameters the restriction effect can be considerable for large pores and small mixing times, τ_m. In typical exchange rate experiments using clinical MR systems with τ_m > 40 ms, the restriction effect can probably be neglected if pores are small.