[Medical Q&A] Do all examinations in the radiology department involve radiation?

Planner: Chinese Medical Association

Reviewer: Kong Lingyan, deputy chief physician, Peking Union Medical College Hospital

As an important examination department in the hospital, the Radiology Department plays a vital role in modern medical diagnosis. It covers a variety of examination items, including conventional X-ray examination (currently usually using digital X-ray photography DR), electronic computed tomography (CT), magnetic resonance imaging (MRI), nuclear medicine examination and interventional radiology.

X-ray examinations and CT examinations involve radiation. X-ray examinations, such as common chest films, use X-rays to penetrate the human body. Since different tissues in the human body absorb X-rays to different degrees, an image is formed on the film. Although the radiation dose of a single X-ray examination is relatively low, if it is performed multiple times in a short period of time, the radiation dose will accumulate and cause potential harm to the body. CT examinations are also based on the principle of X-rays, but they can provide more detailed tomographic images. However, the radiation dose of CT examinations is usually higher than that of ordinary X-ray examinations because it requires scanning the human body from multiple angles. However, the current CT equipment technology is constantly improving, and efforts are also being made to reduce the radiation dose while ensuring image quality.

MRI examinations do not involve any ionizing radiation. MRI uses magnetic fields and radio frequency pulses to image the human body. It is a safe, non-invasive examination method that does not cause radiation damage to the human body. Therefore, for special populations such as pregnant women and children, MRI is generally considered a safer examination option.

In order to reduce the potential impact of ionizing radiation on the human body, radiology staff will take a series of protective measures, such as using lead clothing to protect the patient's sensitive parts, optimizing scanning parameters to reduce radiation dose, and avoiding unnecessary repeated examinations as much as possible.