Abstract

We studied to evaluate CT characteristics of bronchogenic cysts. We retrospectively evaluated CT of 11 patients with pathologically proved bronchogenic cyst. Precontrast and postcontrast CT scan was performed in all. We analyzed CT with viewpoints of location, size, attenuation on pre- and postcontrast scan, and calcification. Three of 11 bronchogenic cysts were intrapulmonary in location and eight were located in the mediastinum. Two of 3 intrapulmonary bronchogenic cysts were located in the right lower lobe, and the remaining one was left lower lobe. Intrapulmonary bronchogenic cysts ranged from 6cm to 12cm in diameter (average, 9.7 cm). On Cr, intrapulmonary bronchogenic cysts appeared as thin-wall air cyst, homogenous water attenuation and soft tissue attenuation with air bubble respectively. Mediastinal bronchogenic cysts were located in posterior mediastinum (n=5), superior mediastinum (n=2), middle mediastinum (n=1) respectively. These cysts ranged in size from 3cm to 8cm in diameter (average 5.0 cm). On CT, five showed homogenous water attenuation, two soft tissue attenuation similar to that of muscle, one air-fluid level. Calcification or contrast enhancement was not detected in any cases. On operative findings, all of intrapulmonary bronchogenic cysts contained dirty pus-like material and all of mediastinal bronchogenic cysts contained whitish or yellowish mucus material. Bronchogenic cysts showed homogenous water density in many cases, homogenous soft tissue density, air-fluid level and air-filled cyst. The constellation of CT findings may be helpful in the diagnosis and Differentiation of bronchogenic cyst.

• Keywords: Bronchogenic cysts, Mediastinal cysts;