Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.08.27.271080v1?rss=1 Authors: Huang, H., Zheng, C.-J., Wang, L.-F., Che-Nordin, N., Wang, Y.-X. Abstract: Objectives: To establish reference values for middle aged subjects and investigate age and gender dependence of liver diffusion MRI parameters. Methods: The IVIM type of liver diffusion scan was based on a single-shot spin-echo type echo-planar sequence using a 1.5-T magnet with 16 b-values. DDVD (diffusion-derived vessel density) was the signal difference between b=0 and b=2 s/mm2 images after removing visible vessels. IVIM analysis was performed with full-fitting and segmented-fitting, and with threshold b-value of 60 or 200 s/mm2, and fitting started from b=2 s/mm2. 32 men (age range: 25-71 years) and 26 men (age: 22-69 years) had DDVD and IVIM analysis respectively, while 36 women (age: 20-71 years) had DDVD and IVIM analysis. Results: DDVD had an age-related reduction noted for women. IVIM results of full fitting had good agreement with segmented fitting with threshold b of 60 s/mm2 results, but less so with results of threshold b of 200 s/mm2. As age increases, female subjects Dslow measure had significant reduction, and PF and Dfast measure had significant increase. Conclusion: DDVD measure suggest that aging may be associated with reduction in liver perfusion. Lower Dslow measurement can lead to artificial higher PF and Dfast measurement, providing the evidence of IVIM modeling of perfusion component is constrained by diffusion component. Copy rights belong to original authors. Visit the link for more info