【摘要】 目的探讨超顺磁性氧化铁粒子(SPIO)增强MRI检测转移性淋巴结的价值。方法取新西兰兔12只,6只于后腿肌肉接种VX2癌细胞,用于建立肿瘤转移性淋巴结模型;6只作为正常对照组。皮下间隙注射SPIO(每肢10 μmol Fe),在注射前和注射后12 h行MRI扫描,序列包括自旋回波(SE )T1WI、SE T2WI和梯度回波(GRE)T2WI,并与病理结果对照。结果平扫时,正常淋巴结和VX2转移淋巴结在三个序列图像上均表现出相似的信号特点。在增强SE T1WI 上,两组淋巴结的信号强度均未见变化;在增强SE T2WI上,正常淋巴结的信号强度不均匀降低,VX2转移组淋巴结的信号强度未见明显变化;在增强GRE T2WI上,正常淋巴结的信号强度明显地均匀降低,而VX2转移组有4个淋巴结信号强度未见降低,2个淋巴结不均匀降低。结论SPIO增强MR成像可用于检测转移性淋巴结。更多还原

【Abstract】 Objective To investigate the value of superparamagnetic iron oxide particles (SPIO) in magnetic resonance (MR) imaging for detecting lymph node metastasis of tumors. Methods Twelve New Zealand rabbits were used in this study, 6 of which received unilateral intra-muscular inoculation of VX 2 carcinoma cells to induce lymph node metastasis of the tumor, and the other 6 served as normal control group. MR images of the lymph nodes of the rabbits were obtained before and 12 h after subcutaneous injection of SPIO, followed by image analysis in correlation with pathological examinations. Results On plain MR images, normal and metastatic lymph nodes showed similar signal characteristics. After administration of SPIO, the signal intensity of both normal lymph nodes and metastatic ones remained unchanged in spin echo (SE) T 1 -weighted images. On SE T 2 -weighted images, the signal intensity of normal lymph nodes significantly decreased heterogeneously, while that of all metastatic lymph nodes remained unchanged. In gradient recalled echo (GRE) T 2 -weighted images, the signal intensity of normal lymph nodes decreased significantly and homogeneously, while that of 4 rabbits in metastasis group remained unchanged, with the signal intensity in the other 2 rabbits decreased heterogeneously. Conclusion SPIO-enhanced MR imaging can be applied to detect lymph node metastasis of the tumors.更多还原