Objective    To assess the value of the 16-slice spiral CT perfusion parameters in diagnosing the solitary nodule or mass in the lungs.     Methods    Sixty-six patients with solitary nodule or mass in the lungs were performed 16-slice spiral CT perfusion scanning with GE Light-Speed ultra 16 CT scanner（1.5-6.0 cm）. The CT perfusion parameters and the histological/cytological results were analyzed comparatively.  Fifty-seven cases （42 men

15 women） were subjected in this study.    Results    Histology/cytology revealed 32 peripheral lung cancers

8 inflammatory solitary nodules or masses

and the other benign solitary nodule or mass were 17 cases. Blood flow(BF)

blood volume (BV) and permeability surface (PS) from both the malignant and the inflammatory cases were significantly higher than those of benign cases （P0.01）. PS was significantly higher in malignant cases than inflammatory ones（P0.01）. No statistically significant differences in BF and BV were found between malignant and inflammatory patients （P0.05）. Mean transit time (MTT) was apparently higher in malignant cases than benign ones（P0.01）

but there was no statistically significant difference in MTT between malignant and inflammatory cases or between inflammatory and benign cases（P0.05）.     Conclusion    Perfusion parameters of multi-slice computed tomography can provide the quantitative perfusion information of the peripheral solitary nodule or mass in the lung

which is helpful in the diagnosis and discrimination.