T1rho MR 成像对评估肝纤维化敏感：在胆管结扎大鼠模型中的实验研究。

T1rho MR imaging is sensitive to evaluate liver fibrosis: an experimental study in a rat biliary duct ligation model.

机构信息

Department of Imaging and Interventional Radiology, Prince of Wales Hospital, the Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.

出版信息

Radiology. 2011 Jun;259(3):712-9. doi: 10.1148/radiol.11101638. Epub 2011 Mar 24.

DOI:10.1148/radiol.11101638

PMID:21436087

Abstract

PURPOSE

To correlate spin-lattice relaxation time in the rotating frame (T1ρ) measurements with degree of liver fibrosis in a rat model.

MATERIALS AND METHODS

The protocols and procedures were approved by the local Animal Experimentation Ethics Committee. Liver fibrosis was induced with biliary duct ligation (BDL). Two studies, 1 month apart, were performed with a 3-T clinical imager. The first study involved longitudinal magnetic resonance (MR) imaging follow-up of BDL rats (n = 8) and control rats (n = 4) on days 8, 15, 21, and 29 after BDL. The second study involved MR imaging of another group of BDL and control rats (n = 5 for each) on days 24 and 38 after BDL. Hematoxylin-eosin and picrosirius red staining were performed in liver specimens from days 8, 15, 24, and 38 after BDL. Repeated-measures analysis of variance was used, and treatment groups were compared (Bonferroni adjustment).

RESULTS

On day 8, there were proliferation of bile duct and inflammatory cell infiltration around portal triads. While there was overlap, BDL rats (n = 8) demonstrated higher mean liver T1ρ values than did control rats (n = 4) on day 8 (46.7 msec ± 2.9 [standard deviation] vs 44.7 msec ± 1.2, P = .4). On day 15, BDL rats demonstrated liver fibrosis with a background of inflammatory infiltration. On day 15, mean T1ρ values in BDL rats could be largely separated from those in control rats (52.6 msec ± 6.0 vs 43.8 msec ± 1.5, P = .02). On day 24, BDL rats had liver T1ρ values 23.5% higher than in control rats (n = 5 for each group, P = .0007). Histomorphometric analysis showed that collagen content increased after surgery from days 8 to 24 (n = 6 for each group, P < .0001), with no further increase between days 24 and 38 (n = 6 for each group, P >.99).

CONCLUSION

In this model, liver fibrosis was detected with T1ρ MR imaging; the degree of fibrosis was correlated with degree of increase in T1ρ measurements.

SUPPLEMENTAL MATERIAL

http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11101638/-/DC1.

摘要

目的

在大鼠模型中，将自旋晶格弛豫时间在旋转框架中的测量（T1ρ）与肝纤维化程度相关联。

材料和方法

本研究方案得到了当地动物实验伦理委员会的批准。肝纤维化是通过胆管结扎（BDL）诱导的。在 3T 临床成像仪上进行了两项研究，相隔 1 个月。第一项研究包括 BDL 大鼠（n=8）和对照组大鼠（n=4）在 BDL 后 8、15、21 和 29 天的纵向磁共振（MR）成像随访。第二项研究包括 BDL 和对照组大鼠（每组 n=5）在 BDL 后 24 和 38 天的 MR 成像。在 BDL 后 8、15、24 和 38 天进行肝组织的苏木精-伊红和苦味酸红染色。采用重复测量方差分析，并对治疗组进行比较（Bonferroni 调整）。

结果

第 8 天，胆管增生和门脉三联体周围炎症细胞浸润。尽管存在重叠，但 BDL 大鼠（n=8）在第 8 天的平均肝脏 T1ρ 值高于对照组大鼠（n=4）（46.7 msec ± 2.9[标准差]与 44.7 msec ± 1.2，P=.4）。第 15 天，BDL 大鼠表现为炎症浸润背景下的肝纤维化。第 15 天，BDL 大鼠的平均 T1ρ 值与对照组大鼠的平均 T1ρ 值基本分离（52.6 msec ± 6.0 与 43.8 msec ± 1.5，P=.02）。第 24 天，BDL 大鼠的肝脏 T1ρ 值比对照组大鼠高 23.5%（每组 n=5，P=0.0007）。组织形态计量学分析显示，术后 8 至 24 天胶原含量增加（每组 n=6，P<0.0001），24 至 38 天之间无进一步增加（每组 n=6，P>.99）。