Multidetector CT for Evaluation of the Extrapleural Space

Abstract

Normal anatomy, multimodality imaging findings, and diseases of the extrapleural space are reviewed, with a focus on CT findings and the diagnostic, prognostic, and therapeutic importance of detecting abnormalities in this space. The extrapleural space (EPS) is an anatomic space at the periphery of the chest that can be involved in a number of disease processes. This space lies between the inner surface of the ribs and the parietal pleura and contains adipose tissue, loose connective tissue, lymph nodes, vessels, endothoracic fascia, and the innermost intercostal muscle. It is often overlooked on cross-sectional imaging studies and almost invariably overlooked on conventional radiographic studies. At conventional radiography, the EPS occasionally can be seen when there is extrapleural fat proliferation, which might be confused with pleural thickening or pleural effusion. Knowledge of the normal anatomy of the EPS depicted at computed tomography (CT) and of the relationship of the EPS with parenchymal, pleural, and chest wall processes is key to the detection of extrapleural abnormalities. Disease entities that most commonly affect the EPS include chronic inflammatory disorders, infection, trauma, and neoplasms. Chronic inflammator...