Lateral chest radiograph shows small bilateral pleural effusions. Enlarged cardiac silhouette with abnormal bands of density noted anterior to the heart (between arrows). Of note, this band of density consists of a central soft tissue sandwiched by lucent stripes.


* Pericardial effusion can be transudate or exudate (pus, blood, infection)
* Symptoms depend on the size and rate of accumulation of effusion
* Chest radiography is not diagnostic of pericardial effusion in most cases
* CT and MRI used to assess size and extent of pericardial effusion
* Measurement of pericardial effusion by CT/MRI tends to be larger than in echocardiography

Radiographic Signs of Pericardial Effusion
All four signs are sensitive (71-100%) but not specific (12-46%).

* Enlarged cardiac silhouette with sharp margin, “water bottle” silhouette
* Pericardial fat stripe (separation of pericardial layers)
* Predominantly left-sided pleural effusion
* Increased transverse cardiac diameter compared with previous radiograph

These images were contributed to this radiology teaching file courtesy of our radRounds Partner,