Central Ray | perpendicular to the midsagittal plane entering the level of T7

Evaluation Criteria

• Apices and costophrenic angles
• Both lungs and 10 ribs visible above the diaphragm
• Heart on the left side
• Spinous process centered demonstrating no rotation of the body
• Adequate air filling the lungs demonstrated by the dark contrast of the lung field.

Shielding: gonads

IR: 14x17in (35x43cm) Crosswise

SID: 72 inches (183cm)

Breathing: Suspended

The history of the PA view x-ray projection of the chest is a long and fascinating one. The first chest x-rays were taken in the early 1890s, shortly after the discovery of X-rays by Wilhelm Roentgen in 1895. These early x-rays were of poor quality and did not provide much information about the internal structures of the chest.

In the early 1900s, a number of improvements were made to x-ray technology, including the development of the grid, which helped to reduce the amount of scattered radiation that reached the film. These...