Abstract: ABSTRACT］Objective： To find a novel method to quantify the angiogenesis of nasal polyps exactly and to study the effect of corticosteroids on microvessel density (MVD) and CD34 in nasal polyps. Methods: The expression of CD34 was determined in 11 cases topically applied of Budesonide (BUD,400?μg/d) for 14 days before endoscopic polypectomy, and in 13 controls without BUD before surgery, and then flow cytometry and immunohistochemistry method were used to quantitatively analyze the MVD. Results: MVD was significantly lower in the BUDusing group than in the control group(P＜0.01), and there was significant difference between the nasal polyp group and control group in flow cytometmry, and a significant correlation between the endothelial cells percentage by flow cytometry and the vessel counts (MVD)by immunochemistry (r=0.675， P=0.011）. Conclusion： Angiogenesis may play an important role in the development of nasal polyps. BUD has effect on nasal polyps by changing the expression of CD34 and decreasing the MVD. In this study, the endothelial cells in nasal polyps are conjugated with antiCD34 monoclonal antibodies labelled with redfluorescent substances, and are quantified by flow cytometry, suggesting flow cytometry as a novel method can quantify the angiogenesis of nasal polyps exactly and quickly.

Key words: Angiogenesis, Nasal polyps, ［KEY WORDS］Flow cytometry, Immunohistochemistry