Establishment of Rabbit VX2 Soft Tissue Tumor Model and Treatment with Percutaneous Ethanol Inj ection under the Guidance of Magnetic Resonance Imaging / 实用放射学杂志

ABSTRACT

Objective Establish rabbit VX2 soft tissue tumor model,and treat it with percutaneous ethanol injection(PEI)under the guidance of magnetic resonance imaging.Make ready for the therapeutic evaluation with functional magnetic resonance imaging. Methods Fifteen healthy New Zealand white rabbits were included in this study.0.2 mL tumor tissue suspensions were injected into the rabbits’posterior limb.14 days later,all rabbits were underwent conventional MRI examination.PET were performed to all the tumors under the guidance of MRI in the next day of the examination.T2 WI was used as guidance and monitoring means.MR com-patible puncture needle with lateral hole was stabed into the lesion center,and inj ected anhydrous ethanol according to the volume of tumors’diameter (1 mL/cm )slowly.the tumors signal characteristics,morphological feature and pathological feature were ob-served pre and post-operation.Results All of the 1 5 rabbits were established soft tissue tumor model successfully;the success rate is 100%.The tumors were oval or round,3-4 cm in diam.MRI scanning showed low signal on T1 WI and high signal on T2 WI be-fore PEI.PEI was performed to all the tumors under the guidance of MR successfully with 3.5 mL ethanol injected into the tumors in average.T2 WI could monitor the ethanol in dispersion and distribution within the tumors clearly.Histologically,tumors were composed of large,uniform,oval/round cells arranged in solid nests which was intensive in the periphery of tumors.Necrosis tissue was apparent in the center of the tumors.10 days after operation,most tissue in the periphery of tumors was coagulative necrosis , only a few tumor cells left.Ranges of necrosis in the tumors center were obviously increased compared with pre-operation.Conclusion Rabbit VX2 tumor of soft tissue model is suitable for the therapeutic evaluation of tumor .It is an animal model which has the characteristic of simple to operate and high rate of suc-cessful.MR T2 WI can monitor the ethanol in dispersion and distribution within the tumors clearly.It is a good guidance and monitoring imaging method of tumor ablation.