A 32-yr-old Korean male patient was admitted to Inha University Hospital, Incheon, Korea due to dyspnea and right chest pain for 1 day. On physical examination, the breath sound in the right lung fields was decreased without shifting of the maximal point of the cardiac impulse. He had a history of the right pneumothorax one and a half years ago, which was treated with tube thoracostomy. He had no history of pulmonary or bronchial tuberculosis before this admission. He was a smoker. The posteroanterior chest radiograph revealed increased radiolucency along with overinflated lung parenchyma and sparse vasculature in the upper half of the right lung. Also note v-shaped branching opacity was in the right parahilar area. Pneumothorax was associated in the right lower pleural cavity (Fig. 1). A 32 Fr chest tube was inserted into the right pleural cavity. The chest CT taken in the state of full expansion of the right lung after tube thoracostomy showed a branching soft tissue density in the region of the posterior segment of the right upper lobe. The orifice of the posterior segmental bronchus was visualized but the orifice of the subsegmental branch of the posterior segmental bronchus could not be visualized separate from the origin (Fig. 2). There were no endobronchial lesions in the bronchial tree on the bronchoscope and each orifice of the segmental bronchi of the right lung was seen normal. His forced expiratory volume at 1-sec (FEV1) was 3.49 L (91%) and forced vital capacity (FVC) was 4.57 L (100%). Perfusion lung scan showed a perfusion defect in the right upper lobe. Exploratory thoracotomy was done via muscle sparing vertical thoracotomy skin incision. There was a localized emphysematous change in the posterior segmental area of the right upper lobe with the apical pleural adhesion and the remaining lungs were normal. Right upper lobectomy was successfully undertaken. The pathological findings of the resected right upper lobe showed overinflation of the posterior segment. There were no obstructed lesions of the orifices of the three segmental bronchi of the right upper lobe. However, one of the subsegmental branch of the posterior segmental bronchus was obstructed and there was a 2.5x1.5x1.5 cm sized cystic mass containing brownish mucus material at the distal portion of the obstructed subsegmental bronchus. The cystic mass was not connected with other bronchial trees. Microscopically the distal air spaces of the atretic segmental bronchus showed overinflation only. However the foci of the subpleural bullae in the overinflated segment were observed (Fig. 3). His postoperative course was uneventful. He was discharged on the post-operative 7th day. He has been well 1.6 yr after the operation.
Chest CT scan shows a branching soft tissue density in the region of the posterior segment of the right upper lobe with marked decrease in attenuation and vascularity. The subsegmental branch of the posterior segmental bronchus could not be traced distal to this (arrow) posterior segmental bronchus.