The Study of CT Appearances of Pulmonary Hamartoma and Relative Pathology

Objective To research the appearances of CT and pathology in pulmonary hamartoma so as to improve the CT diagnostic accuracy.Methods The CT and pathological findings of 25 cases of pulmonary hamartoma were analyzed. Dynamic contrast enhancement CT scanning were performed in 17 cases without calcification. All cases were confirmed by surgical operation and pathology.Results All hamartomas had smooth edge on CT. Focal fat without calcification inside were present in 8 of 25 cases, focal fat and calcification inside in 6 of 25 cases (24%), calcification without fat inside in 2 of 25 cases (8%). The CT contrasted value was less than 20 HU in16 of 17 cases (88.24% ). Contrast-enhancing septa were present in 13 of 17 cases(76.47%). The enhancing septa corresponded to loose connective tissue between cartilaginous core. Pathologically, all hamartomas had complete fibrous capsule around them. Cartilage ,broncheal gland, smooth muscle and fibrous connective tissue were found in all cases, and fat and calcification were found in 13 (52%) and 8 (32%) respectively.Conclusion Some specific CT features, including smooth edge, calcification and fat inside, are useful for diagnosis of pulmonary hamartoma. Dynamic contrast enhancement CT scanning is useful for differentiating pulmonary hamartoma with peripheral lung carcinoma.