CT diagnosis of lung cystic echinococcosis with infections

Objective: To analyze the CT findings of lung cystic echinococcosis with infections, and to assess the value of CT examination. Methods: The CT characters of 23 cases of pathologically proved lung cystic echinococcosis were analyzed and CT findings were compared with pathology. Results: All 23 cases of lung cystic echinococcosis appeared as single cystic lesions. Fifteen cases appeared in the right lung, and the other 8 in the left. The lesions located in lower lobe were more than those in the upper lobe. According to the CT examination, it could be divided into two types: (1) simple lesion (7 eases) appeared as irregular solid mass with different size, crude edge, and lobulation, and with fiber shadows in the lung field around the lesions. In 6 cases, curvilinear or spotty calcification occurred in the lesions. (2) echinococcosis as a bag (16 cases) appeared as a mass with cystic changes in lung tissue with different size and off-center cystic cavity. The lesions took the form of ball or irregular shape. The edge was crude. Around the focus, prickle-like or patchy changes were detected. Ruptured lesions showed 'water snake' or 'flow ribbon' signs in 4 cases. In 7 cases, calcification occurred on the cystic wall or extended into the inside contents. Conclusion: CT could accurately demonstrate the location, appearance, internal structure, and adjacent situation of the cystic echinococcosis, providing valuable information for correct diagnosis and treatment. (authors)