肝素标记SPIO增强MRI诊断大鼠肝癌病灶

Heprin Labelled Superparamagnetic Iron Oxide Particles as a Liver MR Contrast Agent for Diagnosis of Microhepatocellular Carcinomas in Rat Models

目的:探讨肝素标记超顺磁氧化铁粒子(HepSPIO) 对大鼠肝癌灶的增强作用。材料和方法:应用Gouys 法测定磁化率;应用二乙基亚硝胺建立大鼠化学诱导性肝癌模型;观察静注Hepspio 前后大鼠肝癌的显示情况,并与病理检查对照分析。结果:HepSPIO 的磁化率为201-5 ×10 - 3/g(25 ℃) ;4 只大鼠肝癌模型共有27 个瘤结,平均直径2-4 ±1-3m m 。增强后质子加权像癌灶检出率由平扫的33-3 % (9/27) 提高到74-1 % (20/27) ,病灶对比度/ 噪声比(CNR) 由0-7±1-9 提高至4-2 ±4-0 ;T2 加权像癌灶检出率由平扫的59-3 % (18/27) 提高到77-8 % (22/27) ,CNR 由2-8 ±2-1 上升至3-9 ±3-3 。结论:HEPSPIO 是一种新型磁共振肝网状内皮系统显影剂,对提高肝脏微小病灶的检出率有重要帮助。

Purpose: To evaluate the potential values of heparin coated superparamagnetic iron oxide particles (Hep SPIO) as liver MR contrast agent for diagnosis of microhepatocellular carcinomas (MHCCs) in rat models. Materials and Methods: A suspension of Hep SPIO was developed here by reaction of Fe 3+ and Fe 2+ in the presence of heparin in alkaline condition. Rat models carrying MHCCs were induced by oral administration of diethylnitrosamine (n=4). MHCCs were demonstrated on plain and Hep SPIO enhanced images. Then, MR findings were correlated with pathological changes. Results: The magnetic susceptibility of Hep SPIO was 201.5×10 -6 /per gram Fe (at 25℃). In 4 rat models, 27 MHCCs were found at autopsy. After injection of Hep SPIO, on proton density weighted images, the tumor detection rate increased from 33.3% (9/27) to 74.1% (20/27) (p<0.01), tumor to liver contrast/noise (CNR) raised from 0.7±1.9 to 4.2±4.0 (p<0.01); on T 2 weighted images, the tumor detection rate raised from 59.3% (18/27) to 77.8% (22/27) (0.01<p<0.05), while the CNR increased from 2.8±2.1 to 3.9±3.3 (0.01<p<0.05). Conclusion: Hep SPIO has substantial potential as a liver MR contrast agent. It is quite helpful for improving detection of tiny tumor foci in liver.