What does blunting of the costophrenic angle mean?

Blunting of the costophrenic angle (also known as blunting of the costophrenic sulcus) is a chest radiograph sign usually indicative of a small pleural effusion. It may be seen on either frontal or lateral erect projections.

What is the normal angle of costophrenic effusion?

The normal angle usually measures thirty degrees. With pleural effusion, fluid often builds up in the costophrenic angle (due to gravity). This can push the lung upwards, resulting in “blunting” of the costophrenic angle. The posterior angle is the deepest.

What are the costophrenic angles?

In anatomy, the costophrenic angles are the places where the diaphragm ( -phrenic) meets the ribs ( costo- ). Each costophrenic angle can normally be seen as on chest x-ray as a sharply-pointed, downward indentation (dark) between each hemi-diaphragm (white) and the adjacent chest wall (white).

How much pleural fluid is needed for costophrenic angle blunting?

It has been found that approximately 200 mL pleural fluid needs to be present for blunting of a costophrenic angle to be visible on a lateral chest radiograph. It is important to recognize that this sign is far from pathognomonic of a pleural effusion.

Is the costophrenic angle a sign of chronic obstructive pulmonary disease?

The costophrenic angle is not visualised (yellow arrow). At least two signs of chronic obstructive pulmonary disease (hyperinflation, flattened diaphragm, tubular cardiac silhouette, rounded costophrenic angle, prominent bronchovascular markings) were reported in 2.06% (n=29) of total radiographs and was the most common probably relevant IF.

Does pleural fluid affect the posterior costophrenic angle?

On the other hand as little as 50ml of pleural fluid may cause blunting of the posterior costophrenic angle on a lateral chest radiograph (Light 2005). The chest radiograph showed some subtle consolidation at the left costophrenic angle.

What is costophrenic blunting without other signs of pleural effusion?

Isolated costophrenic blunting without other signs of pleural effusion is estimated to represent approximately 300mL of pleural fluid. An abnormally sharp costophrenic angle with a deep, sharp sulcus on a supine chest x-ray. A sign of pneumothorax.