Impact of <i>b</i>-Value Sampling Scheme on Brain IVIM Parameter Estimation in Healthy Subjects

• DOI: 10.2463/mrms.mp.2019-0061
• Publication Date: 2019-10-14T22:04:07Z
• Authors: Stéren Chabert; Jorge Verdu; Gamaliel Huerta; Cristian Montalba; Pablo Cox; Rodrigo Riveros; Sergio Uribe; Rodrigo Salas; Alejandro Veloz
• Keywords: Intravoxel incoherent motion; Coefficient of variation

Intravoxel incoherent motion (IVIM) analysis has attracted the interest of clinical community due to its close relationship with microperfusion. Nevertheless, there is no clear reference protocol for implementation; one questions being which b-value distribution use. This study aimed stress importance sampling scheme and show that an optimized decreases variance associated IVIM parameters in brain respect a regular healthy volunteers.Ten volunteers were included this study; images acquired on 1.5T MR scanner. Two distributions 16 b-values used: considered 'regular' association used other studies, 'optimized' according previous studies. adjusted bi-exponential model, using two-step method. Analysis was undertaken ROI defined Automated Anatomical Labeling atlas, compared total 832 ROI.Maps fewer speckles obtained distribution. Coefficients variation did not change significantly estimation diffusion coefficient D but decreased by approximately 39% pseudo-diffusion 21% perfusion fraction. Distributions found different 50% cases fraction, 80% 17% coefficient. Observations across areas range average values smaller case.Using distribution, data are sampled way signal decay better described less fitted parameters. The increased precision gained could help detect small variations