Clinical Importance of Echogenic Swirling Pleural Effusions.

Thoracic sonography is an important tool in diagnosis and assessment of pleural effusions and can provide valuable information about the characteristics of accumulated pleural fluid, in addition to improving the safety of thoracentesis. In addition to the 4 classic sonographic pleural effusion patterns (anechoic, complex nonseptate, complex septate, and homogeneously echogenic), an echogenic swirling pattern has been previously described, which was originally thought to be associated with malignant effusion. Two cases of pleural effusion with an echogenic swirling pattern are described below, illustrating that this sonographic finding can be seen in both exudative and transudative effusions.