Pericardial effusion

Sagital CT image of the same patient correlates well with lateral radiograph in companion Chest X-ray.

It shows that the 'sandwich' seen anterior to the heart represents pericardial effusion (star) bounded by epicardial and pericardial fat.

Facts

* 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, RadiologyinThai.com.