Which condition is characterized by blunting of the costophrenic angle on imaging?

The condition characterized by blunting of the costophrenic angle on imaging is pleural effusion. In pleural effusion, there is an accumulation of fluid in the pleural space, which can lead to a change in the normal appearance of the costophrenic angle on chest X-rays or other imaging studies.

As fluid collects in the pleural space, it causes the costophrenic angle—a location where the diaphragm meets the chest wall—to become obscured or blunted. This blunting is a classic sign of pleural effusion and can be used to differentiate it from other respiratory conditions. In imaging, the presence of fluid will appear as a meniscus along the lateral chest wall, indicating the extent of the effusion.

On the other hand, conditions like atelectasis, pneumonia, and ARDS may present with other imaging findings. Atelectasis typically reveals volume loss and may show increased opacity rather than blunting of the angle. Pneumonia often presents with infiltration and consolidation patterns, while ARDS shows bilateral infiltrates that don’t typically affect the costophrenic angle in the same manner as pleural effusion. Therefore, the characteristic blunting of the costophrenic angle distinctly aligns with ple