What is the role of the grid in X-ray

The grid is made of lead foils arranged in parallel or at a certain slope at a certain distance. The lead strips are filled and fixed with aluminum, paper or wood strips that can penetrate X-rays, and both sides are supplemented with aluminum or synthetic resin protective layers. become. Clinically, scattered rays are extremely harmful in X-ray photography. Biological cells are inhibited and damaged after being irradiated by X-rays. Therefore, scattered rays increase unnecessary radiation dose and radiation damage even for subjects and staff. , It has increased the contrast of X-ray photos and even the possibility of losing useful information. For this reason, it is very important to remove the scattered rays in X-ray photography, and the wire grid is designed for this purpose.
Generally, many people think that the higher the grid ratio of the grid, the stronger the ability to eliminate scattered rays. This statement is wrong. The greater the grid density, the greater the dose received by the patient. When using a wire grid, it is not that the higher the grid ratio, the greater the grid density, the better. If you use high-kV photography, it is best to use a 10:1 or 12:1 grid. When shooting a part with a thickness of more than 14CM, generally use an 8:1 or 10:1 grid.

Author：Lillian