Effect of ageing and pulmonary inflammation on the incidence and number of cross-bridging structures in pneumothorax patients

Background: There is an improved prognosis for T4 non-small-cell lung cancer in patients who show particular patterns of direct mediastinal invasion. The particular patterns suggest the presence of direct pathways other than the pulmonary hilum between each of the lungs and the mediastinum/chest wall. Purpose: To determine the incidence and number of such direct pathways in pneumothorax patients as well as the factors that affect the development of these pathways. Material and Methods: Two radiologists independently analyzed multidetector computed tomographic images of 81 patients with pneumothorax to assess the incidence and distribution pattern of the crossbridging structures in the pleural cavity. Results: Cross-bridging structures were observed in the right pneumothorax in 34/54 (63%) patients and in the left pneumothorax in 19/32 (59%) patients. The number of cross-bridging structures was found to be positively correlated with ageing and pulmonary disease. The distribution patterns of cross-bridging structures were found to be specific in formation and often in repeated locations, regardless of the presence of pulmonary disease or the age of the patient. Conclusion: Cross-bridging structures in pneumothoraces were found more frequently in older patients and in patients with pulmonary disease. However, some of the cross-bridging structures may have been congenital because of their specific formations and repeated locations.