Imaging techniques for pleural space infections

Radiology plays a central role in the evaluation and management of pleural space infections. Conventional radiographs, including decubitus films, remain the primary radiological study in the detection of parapneumonic pleural effusions. Loculated collections develop as a result of visceral-to-parietal pleural adhesions and appear radiographically as longitudinally oriented, lenticular-shaped opacities. Contrast-enhanced computed tomography scans accurately distinguish lung abscess from loculated empyema and provide a global view of the extent and complexity of the pleural collection. Sonography allows portable bedside examination of critically ill patients and is useful in the detection and sampling of small effusions. Real-time ultrasound evaluation of pleural collections accurately determines the size and nature of the effusion and may be useful in predicting the success of thoracentesis. As cross-sectional studies are obtained in the majority of patients with complex pleural space infection and provide valuable information, the precise clinical utility of computed tomography scans and ultrasound in these patients remains undetermined.