DWI评价无水乙醇注射治疗兔软组织VX2肿瘤疗效

Diffusion weighted imaging for evaluation of therapeutic efficiency of percutaneous ethanol injection of rabbit soft tissue VX2 tumor

目的:采用磁共振扩散加权成像(DWI)评价经皮穿刺无水乙醇注射(PEI)治疗兔软组织VX2肿瘤的疗效。方法:选取15只健康新西兰大白兔作为实验对象,在其右侧大腿内侧注射VX2肿瘤组织悬浮液约0.1ml,制备成荷瘤兔,于肿瘤组织接种后第14天行常规磁共振扫描及多b值(300、500、700、900s/mm2)DWI扫描,扫描后第2天在磁共振导引及监视下行无水乙醇注射治疗。分别于PEI治疗后第1、7、10天行磁共振扫描。观察PEI治疗前、后肿瘤信号特点的变化,采用配对t检验比较肿瘤实质、正常肌肉组织、坏死组织的ADC值以及治疗前后肿瘤实质的ADC值。结果:PEI治疗前肿瘤组织T1WI呈等信号或稍低信号,T2WI呈明显高信号,DWI上呈高信号。相同b值下ADC(肿瘤实质)<ADC(正常肌肉组织)<ADC(坏死组织)(P<0.05);而随着b值的增大,各组织的ADC值减小。PEI治疗后肿瘤组织DWI仍呈高信号,但较PEI治疗前低。PEI治疗后第1、7、10天肿瘤实质的ADC值均较术前增高(P值均<0.05),且治疗后10天的ADC值较治疗后1天的ADC值高(P<0.05)。结论:无水乙醇注射治疗兔软组织VX2肿瘤具有一定的疗效,治疗后早期肿瘤实质的ADC值即出现变化。DWI可以用来评价无水乙醇注射治疗兔软组织VX2肿瘤的疗效。

Objective.. To evaluate the effect of percutaneous ethanol injection （PED of rabbit soft tissue VX2 tumor with diffusion weighted MR imaging （DWI）. Methods-. Fifteen healthy New Zealand white rabbits were involved in this study. 0. lml of the living tumor cell suspensions was injected into the medial posterior limb proximally. All the rabbits un- derwent conventional MRI and multi-b-value （300,500,700,900s/mm2） DWI sequence on day 14 after tumor cell innocula- tion. PEI was performed on day 15. Conventional MRI and DWI were performed on 1st, 7th, 10th day after PEI. The ADC values pre- and post-PEI using paired t-test. Results： Rabbit soft tissue VX2 tumor exhibited hypointense on T1 WI and hy- perintense on T2 WI and DWI before PEI respectively. The mean ADC values in tumor, necrotic tissue and muscle were significantly different （P〈0.05）. The mean ADC value of the tumors was smaller than that of the necrosis tissues. The mean ADC value before PEI was significantly lower than the ADC values lst,7th and 10th day after PEI （P〈0.05）. The mean ADC value 1st day after PEI was significantly lower than mean ADC 10th day after PEI （P〈0.05）. Conclusion： Percutane- ous ethanol injection is effective for rabbit soft tissue VX2 tumor. DWI may play an important role in the evaluation of effect of percutaneous ethanol injection of soft tissue tumor.