兔VX2舌癌转移淋巴结经静脉超声造影实验研究

目的研究经静脉超声造影后兔VX2舌癌转移淋巴结的增强形态和增强方式，探讨应用静脉超声造影诊断颈淋巴转移的可行性。方法将20只新西兰大白兔随机分为2组：VX2舌癌颈淋巴转移组（12只）和颈淋巴结炎性增生组（8只）。经耳缘静脉注射超声造影剂，采用实时灰阶谐波超声造影成像技术观察两组淋巴结的增强形态和增强方式。采用Fisher确切概率法分析增强的形态和方式。结果超声造影后，炎性增生组和淋巴转移组每只兔的每侧颈部均检出1枚增强的淋巴结。炎性增生组淋巴结均为均匀增强，且增强自中央开始。淋巴转移组中11只兔颈淋巴结为不均匀增强，其中3只为从周边开始的不均匀增强，8只为从周边及中央开始的不均匀增强；另1只兔颈淋巴结为均匀增强，增强从中央开始。结论超声造影后，肿瘤转移淋巴结增强表现为从周边开始或周边和中央开始的不均匀增强，此特征对诊断颈淋巴转移有一定的参考价值。

Objective To investigate the sonographic features of the cervical lymph nodes in rabbit VX2 tongue carcinoma model and hyperplasia cervical lymph nodes model using gray scale contrast-enhanced ultrasonography (CEUS) after intravenous administration of SonoVue (a sonographic contrast agent) and to evaluate the potential utility of CEUS in detecting early metastatic cervical lymph nodes in the rabbit VX2 tongue carcinoma model.Methods Twenty New Zealand rabbits were placed into 2 groups,12 for node metastasis and 18 for node hyperplasia.Cervical CEUS was performed in the rabbits of both groups before and after intravenous administration of SonoVue ( 0.6 ml ). The phase,pattern,beginning area and echogenicity of enhancement of the lymph nodes on the right neck were observed and recorded.Dissection of the lymph nodes were guided by the marks made during CEUS and examined histopathologically.Results Only one enhanced lymph node was detected on the right neck of each rabbit in both groups.All 8 cases in the hyperplasia group showed homogeneous enhancement starting from centre,while in the metastasis group 1 case showed homogeneous enhancement starting from the centre, 3 cases showed inhomogeneous enhancement starting from periphery,and 8 cases showed inhomogeneous enhancement starting from both centre and periphery.The one enhanced lymph node on the right neck in each rabbit in both groups was dissected.Pathological examination showed all of the 12 lymph nodes in the metastatic group were with cancer metastasis.Conclusions CEUS indicates hyperplastic lymph nodes showing homogeneous enhancement starting from centre,while most metastatic lymph nodes showing inhomogeneous enhancement starting from periphery or from both periphery and centre,which can be used as a characteristic to distinguish neoplastic nodes from benign nodes by CEUS.