Hepatic implanted tumor in rat: superparamagnetic iron oxide enhanced MR imaging
- VernacularTitle:大鼠种植型肝癌的超顺磁性氧化铁磁共振增强实验研究
- Author:
Li WANG
;
Jianming TIAN
;
Jianping LU
- Publication Type:Journal Article
- Keywords:
Contrast media;
Animals, laboratory;
Liver neoplasms;
Magnetic resonance imaging
- From:
Chinese Journal of Radiology
2000;0(12):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To make a curve of dose grads liver signal of superparamagnetic iron oxide (SPIO) in normal rats, to compare lesion to liver contrast noise ratio (C/N) and to assess the ability on MR imaging before and after SPIO injection. Methods Group one: 72 normal SD rats divided into 18 specimen groups at random, underwent MR enhancement with 0,2,5……280 ?mol Fe/kg SPIO respectively after plain scanning. The signal to noise ratio of liver was measured and a curve of dose grads liver signal was made in order to find an appropriate dose for enhancement. Group two: 38 rats with 43 implanted liver adenocarcinomas underwent T 1 and T 2 weighted MR imaging before and after the injection of SPIO agent. Evaluations included enhancing characteristics of the tumors, counting the number of lesions and statistical analysis of quantitative changes in the signal intensity of both lesions and normal liver. Results On SPIO enhanced T 2 weighted and T 1 weighted MR images, the signal intensity of liver was reduced to peripheral noise on the dose of 10 ?mol Fe/kg and 40 ?mol Fe/kg respectively. The highest contrast to noise ratio (C/N) could be acquired on the dose of 20 ?mol Fe/kg on enhanced T 2 weighted MR images; its C/N almost doubled compared with that of enhanced T 1 weighted and unenhanced T 2 weighted MR images. The C/N of unenhanced T 1 weighted MR images was lowest. The number of lesions detected on enhanced MR imaging was the same as that of the pathology, and enhanced MR imaging was superior to unenhanced MR imaging in tumors smaller than 3 mm, of 36.3% escaped detection on unenhanced MR images. Conclusion Good enhancement effect of SPIO on T 1 and T 2 weighted MR imaging could be acquired at the dose of 20 ?mol Fe/kg, its detecting ability approached that of gross pathology, and the best contrast to noise ratio was found on T 2 weighted enhanced MR image.