Abstract: Objective The aim of this study was to investigate the diagnostic value of CT enhancement in different size and density of solitary pulmonary nodules(SPN). Methods A retrospective cohort study was performed on 204 patients with SPN.The pathological results were used as reference standards to compare the difference of CT enhancement peaks in different sizes and densities of SPN,and to explore the differential diagnosis of different pathological types of SPN. Results CT enhancement was more valuable in the differential diagnosis of SPN with solid and/or diameter of 2~3 cm(OR=5.15,95%CI:2.62~10.14;OR=5.39,95%CI:1.89~15.39).However,in partial solid,the differentiation of benign and malignant in nodules with diameter ≤2 was poor;the peak of CT enhancement(≥15 HU)was statistically significant in different pathological types of SPN.The positive rate of CT enhancement gradually increased with increasing diameter and density. Conclusion In the differential diagnosis of SPNs,CT enhancement scan should be reasonably selected with reference to the density,diameter and possible pathological findings of the nodules.

Key words: Lung neoplasm, Diagnosis,Differential, Tomography, X-Ray computed, Pathology