钆喷替酸葡甲胺-白蛋白增强MR淋巴造影鉴别良恶性淋巴结的实验研究

Human serum albumin-gadolinium diethylenetriamine pentaacetic acid-enhanced positive MR lymphography:differentition of the benign from metastatic lymph nodes in an experimental study

目的初步探索组织间隙应用钆喷替酸葡甲胺-白蛋白(HSA-Gd-DTPA)的阳性 MR 淋巴造影在鉴别良、恶性淋巴结中的价值。方法新西兰兔12只,体重2.0～2.5 kg。6只兔单侧后腿肌肉注射蛋黄乳胶,用于建立腘窝淋巴结的反应性增生模型(反应性增生组),另6只兔单侧后腿肌肉接种 VX_2肉瘤,用于建立腘窝淋巴结肿瘤转移模型(VX_2肉瘤转移组),对侧正常腘窝淋巴结用作对照(正常组)。分析各组腘窝淋巴结在平扫及组织间隙注射0.04～0.05 mmol/kg HSA-Gd-DTPA24 h后的 MRI 特征并与病理检查对照。结果平扫时,正常组(共计6个淋巴结)、反应性增生组(共计8个淋巴结)和 VX_2肉瘤转移组(共计10个淋巴结)均表现为 T_1WI 上等或稍高信号,T_2WI 上高信号。增强后24 h,正常组和反应性增生组淋巴结呈明显的均匀强化,而8个转移性淋巴结分别表现为环状、云絮状和"充盈缺损"等不均匀的强化模式,2个淋巴结为完全不强化。结论组织间隙应用HSA-Gd-DTPA 的阳性 MR 淋巴造影可准确鉴别良、恶性淋巴结。

Objective To investigate the value of HSA -Gd-DTPA （Human Serum Albumin Gadolinium diethylenetriamine pentaacetic acid）-enhanced positive MR lymphography for differentiation of the benign from metastatic lymph nodes. Methods Twelve New Zealand rabbits weighted at 2. 0--2. 5 kg were used. Six hyperplastic reactive popliteal lymph nodes were induced by intramuscular injection of 0. 5 ml egg yolk emulsion （EYE） into the unilateral hindleg, and six tumor-bearing popliteal lymph nodes were induced by intramuscular injection of 0. 5 ml VX2 tumor cell suspension into the unilateral hindleg, the contralateral lymph nodes were chosen as normal control group. MR features before and 24 h after interstitial administration of HSA-Gd-DTPA （0. 04 mmol/kg） were analyzed and correlated with pathological findings. Results The normal, hyperplastic reactive and VX2 tumor-bearing popliteal lymph nodes showed moderate or slightly high signal intensity on unenhanced T1 -weighted images and high signal on T2-weighted images. The normal and hyperplastic reactive lymph nodes showed homogeneous and remarkable enhancement on SE T1WI 24 h after the administration of HSA-Gd-DTPA, while 8 metastatic lymph nodes showed ring or patchy enhancement, and 2 metastatic lymph nodes showed no enhancement. Conclusion HSA-Gd-DTPA- enhanced positive MR lymphography can accurately differentiate the benign from metastatic lymph nodes.