Faculty Collaboration Database

The effect of low b-values on the intravoxel incoherent motion derived pseudodiffusion parameter in liver. Magn Reson Med 2015 Jan;73(1):306-11

Date

01/31/2014

Pubmed ID

24478175

Pubmed Central ID

PMC4317387

DOI

10.1002/mrm.25109

Scopus ID

2-s2.0-84919844948 (requires institutional sign-in at Scopus site)   91 Citations

Abstract

PURPOSE: To examine the effect of low b-values (0 < b < 50 s/mm(2)) on the calculation of the intravoxel incoherent motion (IVIM) derived pseudodiffusion parameter in the normal liver.

METHODS: Simulations were performed to examine the effects of adding low b-values on the pseudodiffusion parameter. Low b-values were cumulatively added to the distribution and the IVIM signal was generated with varying pseudodiffusion values. The signal was fit with the IVIM model after the addition of Gaussian noise, and the simulated values were compared with the true values. In addition, the livers of eight control subjects were imaged using respiratory-triggered DWI. Pseudodiffusion was calculated with and without low b-values and compared.

RESULTS: Pseudodiffusion tended to be underestimated when low b-values were not included in the b-value distribution as predicted by simulations and confirmed with in vivo imaging. The number of outlier values was also reduced as more low b-values were added.

CONCLUSION: In conclusion, this study showed pseudodiffusion in the liver tended to be underestimated when too few low b-values (0 < b < 50 s/mm(2)) were included in the distribution. Therefore, it is recommended to include at least two low b-values when performing liver IVIM studies.

Author List

Cohen AD, Schieke MC, Hohenwalter MD, Schmainda KM

Authors

Mark D. Hohenwalter MD Associate Dean, Executive Director, Professor in the Radiology department at Medical College of Wisconsin
Kathleen M. Schmainda PhD Professor in the Biophysics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adolescent
Adult
Algorithms
Computer Simulation
Diffusion Magnetic Resonance Imaging
Female
Humans
Image Enhancement
Image Interpretation, Computer-Assisted
Imaging, Three-Dimensional
Liver
Male
Middle Aged
Models, Biological
Motion
Reproducibility of Results
Sensitivity and Specificity
Young Adult