PT  - JOURNAL ARTICLE
AU  - Ben-Heng Xiao
AU  - Hua Huang
AU  - Li-Fei Wang
AU  - Shi-Wen Qiu
AU  - Sheng-Wen Guo
AU  - Yì Xiáng J. Wáng
TI  - Validation study of a diffusion MRI derived vessel density biomarker for detecting viral hepatitis-b induced liver fibrosis
AID  - 10.1101/633024
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 633024
4099  - http://biorxiv.org/content/early/2019/07/11/633024.short
4100  - http://biorxiv.org/content/early/2019/07/11/633024.full
AB  - Aim Liver vessel density can be evaluated by an imaging biomarker DDVD (diffusion derived vessel density): DDVD/area(b0b2) = Sb0/ROIarea0 – Sb2/ROIarea2, where Sb0 and Sb2 refer to the liver signal when b is 0 or 2 (s/mm2); ROIarea0 and ROIarea2 refer to the region-of-interest on b= 0 or 2 images; and Sb2 may be replaced by Sb15 (b=15). This concept was validated in this study.Materials and Methods Liver diffusion images were acquired at 1.5T. For a scan-rescan repeatability study of 6 subjects, b-values of 0 and 2 were used. The validation study composed of 26 healthy volunteers and 19 consecutive suspected chronic viral hepatitis-b patients, and diffusion images with 16 b-values of 0, 2, 4, 7, 10, 15, 20, 30, 46, 60, 72, 100, 150, 200, 400, 600 were acquired. Four patients did not have liver fibrosis, and the rest were four stage-1, three stage-2, four stage 3, and one stage-4 patients respectively.Results Intraclass correlation coefficient for repeatability was 0.994 for DDVD/area(Sb0Sb2), and 0.978 for DDVD/area(Sb0Sb15). In the validation study, DDVD/area(Sb0Sb2) and area(Sb0Sb15) were 14.80±3.06 and 26.58±3.97 for healthy volunteers, 10.51±1.51 and 20.15±2.21 for stage 1-2 fibrosis patients, and 9.42±0.87 and 19.42±1.89 for stage 3-4 fibrosis patients. For 16 patients where IVIM analysis was performed, a combination of DDVD/area, PF, and Dfast achieved the best differentiation for non-fibrotic livers and fibrotic livers. DDVD/area were weakly correlated with PF or Dfast.Conclusion Both DDVD/area(Sb0Sb2) and area(Sb0Sb15) are useful imaging biomarker to separate fibrotic and non-fibrotic livers, with fibrotic livers had lower measurements.