Magnetic resonance diffusion-weighted imaging: quantitative evaluation of age-related changes in healthy liver parenchyma

Abstract

The purpose of this study was to verify in healthy liver parenchyma the possible influence of age on DwI-related parameters: apparent diffusion coefficient (ADC), perfusion fraction (PF), diffusion and pseudodiffusion coefficient (D and D ⁎ ). Forty healthy adult volunteers (age range 26-86 years), divided into four age groups, were prospectively submitted to a breath-hold magnetic resonance diffusion imaging (MR-DwI) (two b values, 0-300 and 0-1000 s/mm 2 ). A smaller cohort of 16 subjects underwent a free-breath multi-b acquisition (16 b values, 0-750 s/mm 2 ). Quantitative analysis was performed by two observers with manually defined regions of interest, on the most homogeneous portion of the right liver lobe. Individual and group statistical analysis of data was performed: ANOVA to establish differences between groups and Pearson correlation coefficient to investigate the association between DwI parameters and age. The mean, S.D. and 95% limits of agreement of ADC values for each age-defined group are reported. ANOVA showed no significant differences between group means (P always N.05). No significant correlation between subjects' age and DwI parameters was established, both in breath-hold and freebreath acquisitions, on the whole range of adopted b values. Our study conducted on healthy liver parenchyma shows that there are no significant differences in ADC, PF, D and D ⁎ of younger or older subjects.

Effects of microperfusion in hepatic diffusion weighted imaging

“…However, Pasquinelli et al showed no significant variations in liver DWI quantitative parameters according to the age of the subject [45]. Therefore, we assumed that the possible effects of age in our cohort are far smaller than the demonstrated significant region dependency of the ADC in the liver.…”

Diffusion analysis with triexponential function in liver cirrhosis

“…Second, the average age of the cirrhotic liver group was significantly higher than that of the normal liver group. However, Pasquinelli et al have reported that there are no significant differences in each derived parameter from DWI ( ADC , PF , D *, and D ) between younger and older subjects on healthy parenchyma. Therefore, it is believed that the results derived from our analyses did not depend on age in this research.…”

Which is the best MRI marker of malignancy for atypical cirrhotic nodules: Hypointensity in hepatobiliary phase alone or combined with other features? Classification after Gd‐EOB‐DTPA administration

“…In fact, recent literature reports have shown that ADC is not satisfactory for differentiating different solid focal liver lesions or grading fibrosis. On the contrary, the results of the studies devoted to the evaluation and follow‐up of the response of metastatic liver tumors to chemotherapy are encouraging (37). An enormous variability has also been observed among acquisition protocols, image postprocessing, and ADC measurements, leading to an increased number of joint initiatives for standardization protocols (38).…”