Spleen micro-perfusion level can be evaluated by DDVD (diffusion derived vessel density): DDVD (unit: au/pixel) = Sb0/ROIarea0 – Sb2/ROIarea2, where Sb0 and Sb2 refer to the spleen signal when b is 0 or 2 (s/mm²) and ROI is ‘region-of-interest’. This study investigated whether spleen DDVD is altered in patients with viral hepatitis-b (VHB) liver fibrosis. Three datasets were retrospectively analysed. Shenzhen data-1 had 25 healthy volunteers and 15 VHB liver fibrosis patients. Changsha data had 24 healthy volunteers and 31 patients with VHB liver fibrosis. Shenzhen data-2 had 67 healthy volunteers. Shenzhen data-2 were measured by reader-1. Shenzhen data-1 were measured by reader-1 and reader-2. For Changsha data, reader-1 measured all subjects, while Reader-2 measured a random selection of 10 healthy volunteers and two patients from each liver fibrosis grade (total=8). Shenzhen data-2 showed in healthy volunteers there was no age-dependent change of spleen DDVD during 20 ∼71 years old, and women had higher spleen DDVD values than those of men's (16.17±7.34 vs. 12.88±5.91, p=0.04). Changsha data by reader-1 showed patients with liver fibrosis had lower spleen DDVD values than those of healthy volunteers (median=16.24 vs. 23.54, p=0.0031). Results of reader-2 showed the same trend (median=11.64 vs. 23.33, p=0.0165). Shenzhen data-1 measured by reader-1 showed medians of spleen DDVD for patients and volunteers were 8.535 and 12.33 respectively; and those measured by reader-2 were 13.89 and 14.31 respectively. We conclude that diffusion MRI shows spleen DDVD, i.e., micro-circulation per volume tissue, is decreased in VHB liver fibrosis patients.

脾脏微灌注水平可以通过DDVD（扩散衍生血管密度）来评估：DDVD（单位：au/pixel）=Sb0/ROIarea0-Sb2/ROIarea2，其中Sb0和Sb2指的是b为0或2时的脾脏信号（ s/mm ²) 并且 ROI 是“感兴趣的区域”。本研究调查了病毒性乙型肝炎 (VHB) 肝纤维化患者的脾脏 DDVD 是否发生改变。对三个数据集进行了回顾性分析。深圳data-1有25名健康志愿者和15名VHB肝纤维化患者。长沙数据有24名健康志愿者和31名VHB肝纤维化患者。深圳data-2有67名健康志愿者。深圳数据2由reader-1测量。深圳数据1由reader-1和reader-2测量。对于长沙数据，reader-1 测量了所有受试者，而 Reader-2 测量了随机选择的 10 名健康志愿者和每个肝纤维化等级的 2 名患者（总计 = 8）。深圳数据2显示，健康志愿者20～71岁脾脏DDVD无年龄依赖性变化，女性脾脏DDVD值高于男性（16. 17±7.34 对 12.88±5.91，p=0.04）。reader-1 的长沙数据显示，肝纤维化患者的脾脏 DDVD 值低于健康志愿者（中位数=16.24 vs. 23.54，p=0.0031）。reader-2 的结果显示出相同的趋势（中位数=11.64 对 23.33，p=0.0165）。reader-1测量的深圳data-1显示，患者和志愿者的脾脏DDVD中位数分别为8.535和12.33；reader-2测得的分别为13.89和14.31。我们得出结论，扩散 MRI 显示 VHB 肝纤维化患者的脾脏 DDVD，即每体积组织的微循环减少。33，p = 0.0165）。reader-1测量的深圳data-1显示，患者和志愿者的脾脏DDVD中位数分别为8.535和12.33；reader-2测得的分别为13.89和14.31。我们得出结论，扩散 MRI 显示 VHB 肝纤维化患者的脾脏 DDVD，即每体积组织的微循环减少。33，p = 0.0165）。reader-1测量的深圳data-1显示，患者和志愿者的脾脏DDVD中位数分别为8.535和12.33；reader-2测得的分别为13.89和14.31。我们得出结论，扩散 MRI 显示 VHB 肝纤维化患者的脾脏 DDVD，即每体积组织的微循环减少。