Intrapulmonary Bronchogenic Cysts: Computed Tomography, Clinical and Histopathologic Correlations

Background/purpose Bronchogenic cysts (BCs) are usually located in the mediastinum and they occur less commonly in the lung parenchyma. This study investigated the findings from computed tomography (CT) images, clinical presentation and histopathologic findings of intrapulmonary BCs. Methods From the last 7 years, the CT images of 20 patients (12 females, 8 males; mean age, 38.8 ± 21.7 year; median age, 34 years) with intrapulmonary BC were available. Contrast-enhanced CT findings were characterized and correlated with clinical presentation and histopathologic findings (using Fisher's exact tests). Results The majority of intrapulmonary BCs were subpleural in location (55%), in the lower lobes (60%), symptomatic (80%), and in adults (90%). Three CT patterns were identified: cyst with content of fluid attenuation (9 patients), cyst with air and fluid content (9 patients), cyst with content of soft tissue attenuation (2 patients). Preoperative diagnosis of intrapulmonary BC was correct in only 20% using the CT criteria of cysts with fluid attenuation and without anomalous blood supply. Cysts with air component were significantly larger than those without air component ( p = 0.0452), but cyst size and air component were not correlated with clinical presentation. Surrounding infiltration or thick wall on CT were significantly correlated with the presence of any clinical symptom ( p = 0.014) or fever ( p = 0.042). CT findings of surrounding consolidation, ground glass opacity or thick wall were significantly correlated with chronic inflammation or pneumonic change on histopathology ( p = 0.0008). Conclusion There is a wide spectrum of intrapulmonary BCs that have CT findings that are correlated with clinical presentations and histopathologic findings. [ J Formos Med Assoc 2007;106(1):8-15]