Imaging
A pleural effusion appears as an area of whiteness on a standard posteroanterior chest X-ray. Normally, the space between the visceral pleura and the parietal pleura cannot be seen. A pleural effusion infiltrates the space between these layers. Because the pleural effusion has a density similar to water, it can be seen on radiographs. Since the effusion has greater density than the rest of the lung, it gravitates towards the lower portions of the pleural cavity. The pleural effusion behaves according to basic fluid dynamics, conforming to the shape of pleural space, which is determined by the lung and chest wall. If the pleural space contains both air and fluid, then an air-fluid level that is horizontal will be present, instead of conforming to the lung space. Chest radiographs in the lateral decubitus position (with the patient lying on the side of the pleural effusion) are more sensitive and can detect as little as 50 mL of fluid. Between 250 and 600mL of fluid must be present before upright chest X-rays can detect a pleural effusion (e.g., blunted costophrenic angles).Chest computed tomography is more accurate for diagnosis and may be obtained to better characterize the presence, size, and characteristics of a pleural effusion. Lung ultrasound, nearly as accurate as CT and more accurate than chest X-ray, is increasingly being used at the point of care to diagnose pleural effusions, with the advantage that it is a safe, dynamic, and repeatable imaging modality.
For patients with malignant pleural effusions, it allows them to continue chemotherapy if indicated. Generally, the tube is in for about 30 days, and then it is removed when space undergoes spontaneous pleurodesis. Tubercular pleural effusion is one of the common extrapulmonary forms of tuberculosis. Treatment consists of antituberculosis treatment (ATT). The currently recommended ATT regime is two months of isoniazid, rifampicin, ethambutol and pyrazinamide followed by four months of isoniazid, rifampicin and ethambutol. See also
Pleural disease
Empyema
Heart failure
Pulmonary embolism
Subpulmonic effusion
Thoracentesis

References
External links

MedlinePlus Encyclopedia: Pleural Effusion
Pleural Effusion Images from MedPix