[Dynamic evaluation of rabbit VX2 hepatic carcinoma with CT and MRI].

OBJECTIVE: To dynamically monitor the growth of rabbit VX2 hepatoma by CT and MRI, and to understand the CT and MRI features during different periods of tumor growth. METHODS: The plain and dual-phase enhanced CT as well as the plain and enhanced MRI were performed in all the 10 rabbit VX2 hepatoma models (with 20 foci) at 1, 2 and 3 weeks after tumor implantation. RESULTS: The detection rate of the VX2 tumors by CT and MRI was low at 1 week after implantation, but was raised to 100% after another week. The tumors were shown to be homogeneously hypointense by unenhanced CT. In arterial phase CT images, peripheral rim enhancement of all the tumors were observed, while the main bodies of the tumors remained hypointense. The nutrient arteries for the tumors stretching straight to the margins of the tumors were detected in 14 (70%) foci and arterial vessels in the tumors visualized in 9 (45%) lesions. On portal venous phase CT the tumors were also shown to be hypointense. The tumors were shown to be homogeneously hypointense in T1-weighted MR images and lightly hyperintense in T2-weighted images, with peripheral rim enhancement of the tumors after injection of the contrast agent. The intensity of most tumors became hetergenerous on plain CT and MRI at week 3 after implantation. CONCLUSION: Rabbit VX2 hepatomas are hypovascular tumors the growth of which can be monitored by CT and MRI effectively.