radiographies

Radiography is a diagnostic imaging modality that uses ionizing radiation to produce images of the internal structures of the body. The images created are called radiographs or X-ray images. Radiography is used in medicine, dentistry, and some industrial applications to visualize bones, organs, and soft tissues that differ in X-ray attenuation.

In a typical radiographic examination, an X-ray tube emits a controlled beam that passes through the patient and is captured by a detector on the opposite side. Dense materials such as bone absorb more X-rays and appear lighter on the radiograph, while less dense tissues appear darker. The resulting projection is a two-dimensional representation of a three-dimensional structure.

There are two main categories: conventional film-based radiography and digital radiography. Digital radiography includes computed radiography using photostimulable phosphors and direct digital radiography with flat-panel detectors. Fluoroscopy provides real-time X-ray imaging, often with contrast agents, enabling observation of movement and function.

Common medical applications include chest radiographs, orthopedic imaging, abdominal studies, mammography, and dental radiography. Radiography also underpins some industrial inspections and nondestructive testing.

Safety is a central consideration because X-rays are ionizing radiation. Exposures are kept as low as reasonably achievable (ALARA) and protective measures such as lead shielding and appropriate technique factors are used. Pregnant patients are typically evaluated with modified protocols or alternative imaging when feasible.

The discovery of X-rays by Wilhelm Conrad Röntgen in 1895 marked the origin of radiography, which has since evolved from film-based systems to highly sensitive digital detectors and advanced image processing.