VX2骨肿瘤模型的超声造影和磁共振初步观察

Observation of contrast-enhanced sonography and MRI in an experimental rabbit model with VX2 bone tumor

目的观察实验兔VX2恶性骨肿瘤模型的超声造影、MRI表现和病理变化,为高强度聚焦超声(HIFU)治疗恶性骨肿瘤影像学随访提供实验模型。方法将VX2肿瘤组织块接种于10只新西兰大白兔胫骨上端干骺端骨髓腔内,3周后进行超声和MRI检查,并进行病理检查。结果10只模型全部接种成功,超声表现为局部骨组织回声消失,胫骨骨皮质破坏,肿瘤内部回声不均匀,彩色多普勒血流成像和彩色多普勒能量图显示肿瘤内彩色血流丰富。注入超声造影剂SonoVue后,肿瘤明显强化,血流灌注方式呈"快进快退"。磁共振平扫T1WI呈等信号,T2WI呈不均匀高信号,增强后明显强化。病理检查镜下见大片肿瘤细胞。结论兔VX2恶性骨肿瘤模型的建立,可为HIFU治疗恶性骨肿瘤提供较为理想的实验模型,并且为治疗前后的影像学评估提供实验依据。

Objective To observe an experimental rabbit model with VX2 malignant bone tumor in imaging manifestations, MRI and pathological changes. Methods Ten New Zealand white rabbits were inoculated with VX2 tumor in cavitas medullaris of proximal metaph tibia. Three weeks after inoculation, the rabbits underwent ultrasonography and MRI scanning. The imaging findings were observed and analyzed. Results The inoculation was successful in 10 rabbits （100 % ）. Local bone tissues disappeared on ultrasound, cortical bone of tibia were destroyed, internal echo of tumor was heterogenous. CDFI and CDE showed abundant colorful blows. After injection of SonoVue, all tumors showed enhanced changes. The perfusion pattern of lesions was ＂fast in and out＂. The tumors displayed similar intensity on T1WI, while inhomogeneous high intensity on T2WI. Contrast-enhanced MRI examination showed obvious enhancement within the tumors. Histological examination showed many tumor cells. Conclusions The VX2 malignant bone tumor model in rabbits was successfully established. It can be served as an ideal experimental model for the study of HIFU treating malignant bone tumor and a reference evidence for imaging features after treatments.