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Diagnosis Pulmonology

Pleural Effusion

The first step is for your doctor to conduct a physical exam and listen to the air flow in your lungs. The following tests may also be used to diagnose and localize the condition:

  • Chest X-ray. These images are often sufficient to reveal the fluid buildup caused by pleural effusion.
  • CT scan. To take images, a thin X-ray beam rotates around the chest area; then a computer program processes the data to construct a three-dimensional, cross-sectional image.
  • Ultrasound. High-frequency sound waves are used to create images of structures inside the body. Ultrasound can detect pleural effusion and show its location.
  • Thoracentesis. In this procedure, a needle is inserted into the chest cavity to remove fluid. Thoracentesis can be used to drain excess fluid, which can then be analyzed to help determine the cause of pleural effusion.
  • Pleural biopsy. This involves removing a tissue sample from the pleura to check for certain diseases and infections that can cause pleural effusion.

UCSF Health medical specialists have reviewed this information. It is for educational purposes only and is not intended to replace the advice of your doctor or other health care provider. We encourage you to discuss any questions or concerns you may have with your provider.