Question

on an upright chest radiograph, the earliest radiographic sign of a pleural effusion is: please select your answer... a mediastinal shift toward the affected side b meniscus sign at the lung apex c air bronchogram sign d blunting of the costophrenic angle

Explanation:

• Mediastinal shift toward the affected side occurs with a large pleural effusion, not the earliest sign.
• Meniscus sign at the lung apex is not the earliest sign of pleural effusion.
• Air bronchogram sign is seen in consolidation (e.g., pneumonia), not pleural effusion.
• Blunting of the costophrenic angle is the earliest radiographic sign of a pleural effusion on an upright chest radiograph as even a small amount of fluid (about 75 - 100 ml) can cause this change.

Answer:

D. Blunting of the costophrenic angle