Chest radiographs are also used to screen for job-related lung disease in industries such as mining where workers are exposed to dust.

Unless a fractured rib is suspected of being displaced, and therefore likely to cause damage to the lungs and other tissue structures, x-ray of the chest is not necessary as it will not alter patient management.

In the UK, the standard chest radiography protocol is to take an erect posteroanterior view only and a lateral one only on request by a radiologist.

Special projections include an AP in cases where the image needs to be obtained stat (immediately) and with a portable device, particularly when a patient cannot be safely positioned upright.

Anteroposterior (AP) Axial Lordotic projects the clavicles above the lung fields, allowing better visualization of the apices (which is extremely useful when looking for evidence of primary tuberculosis).

An increase in the number of viewable ribs implies hyperinflation, as can occur, for example, with obstructive lung disease or foreign body aspiration.

Splaying of the carina can also suggest a tumor or process in the middle mediastinum or enlargement of the left atrium, with a normal angle of approximately 60 degrees.

The right paratracheal stripe is also important to assess, as it can reflect a process in the posterior mediastinum, in particular the spine or paraspinal soft tissues; normally it should measure 3 mm or less.

[7] Localization of lesions or inflammatory and infectious processes can be difficult to discern on chest radiograph, but can be inferred by silhouetting and the hilum overlay sign with adjacent structures.

Diagnosis is aided by noting: The causes include: Fluid in space between the lung and the chest wall is termed a pleural effusion.

The following features should be noted: Pleural effusions may occur with cancer, sarcoid, connective tissue diseases and lymphangioleiomyomatosis.