[CT findings of pulmonary hamartoma with special reference to epithelial-lined clefts and connection with pulmonary arteries].

Purpose: The purpose of this study was to clarify the characteristic CT findings of pulmonary hamartoma.

Materials and methods: The thin-section CT and multiplanar reformation images of 19 pulmonary hamartomas diagnosed by surgical resection were analyzed and correlated with the pathological findings.

Results: Most hamartomas presented lobulated nodules apart from pleura. There was no case in which fat density was recognized. Only one case was recognized as having calcification. Air density in the connection of the side or the inside was pointed out in 5 cases (26%). Air density reflected epithelial-lined cleft. The connection with the bronchus was recognized in 4 cases (21%), and the connection with the pulmonary artery branch was recognized in 10 cases (53%). However, the connection of the pulmonary artery and bronchus could not be pathologically confirmed in most cases. The connection with the pulmonary vein was not recognized in any of the cases.

Conclusion: Air density in the connection of the side or the inside is characteristic of pulmonary hamartoma. Pulmonary artery branches connect beyond half of hamartomas. This finding suggests close relations in the bronchus along the artery. It is important that there is no connection of the pulmonary vein, to differentiate it from lung cancer.