Pericardial Effusion

How do you distinguish cardiomegaly from pericardial effusion?
What are the Common Causes for pericardial effusion?
How would you evaluate a patient suspected to have pericardial effusion by Imaging studies?

CXR, US, CT amd MR have roles in the evaluation of pericardial effusion.

CXR:

In patients with a large pericardial effusion (at least 250 ml), the chest radiograph usually demonstrates

Enlarged cardiac silhouette could be pericardial effusion or cardiac enlargement. Lateral chest radiograph shows sign indicating effusion. Dorsally displaced epicardial fat pad (arrows) indicates that the cardiac silhouette is due to pericardial effusion.

3D Echocardiography: is the radiologic modality of choice for evaluating pericardial effusions.

Pericardial Effusion

Echocardiogram showing fluid surrounding the heart.

 

Case of cardiac tamponade:

CT : is valuable for detecting loculated pericardial effusions and in detecting pericardial thickening

Epicardial fat pad is displaced posteriorly by pericardial effusion. Low density fluid density around heart.

MRI