Yunjung Lee1, Hyeonjin Kim. 1. Department of Radiology, Seoul National University Hospital, Seoul, Korea.
Abstract
PURPOSE: Given the potential confounding effect of fat on apparent diffusion coefficient (ADC) in the liver, we have assessed diffusion tensor imaging in liver fibrosis with minimal effect of fat on ADC and fractional anisotropy (FA). METHODS: Thirty-six mice were used, among which 20 mice were CCl4 treated for fibrosis induction. Diffusion tensor imaging was performed at 9.4T using a spin-echo diffusion tensor imaging sequence with six gradient directions. Hepatic fat fraction obtained by MR spectroscopy was used as hepatic fat content. Fibrosis scores were obtained from histopathology. RESULTS: The hepatic fat fractions of the two animal groups were below 5.5% and not different (5.3 ± 1.5 vs. 4.6 ± 1.1%; P = 0.115). Fibrosis scores were higher in CCl4 -treated mice (0.0 ± 0.0 vs. 2.1 ± 0.7; P < 0.001). Nonetheless, there was no difference in ADC between the two groups (0.711 ± 0.068 × 10(-3) vs. 0.718 ± 0.095 × 10(-3) mm(2) s(-1) ; P = 0.911). The treated group had a lower FA than control (0.552 ± 0.050 vs. 0.586 ± 0.013; P = 0.023). ADC was not correlated with hepatic fat fraction and fibrosis. FA was correlated with hepatic fat fraction (r = 0.418, P = 0.011) and fibrosis (r = -0.411, P = 0.012). CONCLUSION: FA may be more sensitive to mild-to-moderate liver fibrosis than ADC. In addition to ADC, FA may also be sensitive to hepatic fat content, and therefore need careful interpretation in liver fibrosis with concomitant fatty liver.
PURPOSE: Given the potential confounding effect of fat on apparent diffusion coefficient (ADC) in the liver, we have assessed diffusion tensor imaging in liver fibrosis with minimal effect of fat on ADC and fractional anisotropy (FA). METHODS: Thirty-six mice were used, among which 20 mice were CCl4 treated for fibrosis induction. Diffusion tensor imaging was performed at 9.4T using a spin-echo diffusion tensor imaging sequence with six gradient directions. Hepatic fat fraction obtained by MR spectroscopy was used as hepatic fat content. Fibrosis scores were obtained from histopathology. RESULTS: The hepatic fat fractions of the two animal groups were below 5.5% and not different (5.3 ± 1.5 vs. 4.6 ± 1.1%; P = 0.115). Fibrosis scores were higher in CCl4 -treated mice (0.0 ± 0.0 vs. 2.1 ± 0.7; P < 0.001). Nonetheless, there was no difference in ADC between the two groups (0.711 ± 0.068 × 10(-3) vs. 0.718 ± 0.095 × 10(-3) mm(2) s(-1) ; P = 0.911). The treated group had a lower FA than control (0.552 ± 0.050 vs. 0.586 ± 0.013; P = 0.023). ADC was not correlated with hepatic fat fraction and fibrosis. FA was correlated with hepatic fat fraction (r = 0.418, P = 0.011) and fibrosis (r = -0.411, P = 0.012). CONCLUSION: FA may be more sensitive to mild-to-moderate liver fibrosis than ADC. In addition to ADC, FA may also be sensitive to hepatic fat content, and therefore need careful interpretation in liver fibrosis with concomitant fatty liver.
Authors: Gehad A Saleh; Ali H Elmokadem; Ahmed Abdel Razek; Ahmed El-Morsy; Omar Hamdy; Elshimaa S Eleraky; Marwa Saleh Journal: Eur Radiol Date: 2022-08-18 Impact factor: 7.034
Authors: Ahmed Abdel Khalek Abdel Razek; Ahmed Abdalla; Ahmed Megahed; Mohamed Elsayed Ahmed; Suzy Abd ElMabood; Rihame Abdel Wahab Journal: Pol J Radiol Date: 2021-08-02