Filmradiografie

Filmradiografie, or film radiography, is an imaging technique that records X-ray attenuation on photographic film housed in a light-tight cassette. An X-ray beam passes through the patient, and the film captures the exposure as a latent image within a silver halide emulsion, which becomes a visible radiograph after chemical processing.

Key components of film radiography include the cassette with intensifying screens, the radiographic film itself, and a processing pathway. Intensifying screens convert some X-ray energy into visible light, reducing patient dose while maintaining image sharpness. The film provides the spatial resolution and contrast once developed. In modern practice, automatic processors replace manual darkroom steps, though traditional film handling still requires proper light- and chemical-safe procedures.

Image formation occurs after exposure when the film undergoes development, fixing, washing, and drying. The developer reduces exposed silver halide crystals to metallic silver, creating darker areas proportional to the incident radiation. Unexposed crystals are removed by the fixer. The resulting grayscale image represents the relative densities of tissues and structures within the body.

History and status: film radiography was the standard method for radiographic imaging for many decades. It has been largely superseded in many settings by computed radiography and digital radiography, which use reusable phosphor plates or flat-panel detectors and offer streamlined storage, image manipulation, and dose management. Nevertheless, film radiography persists in some clinics, dental practices, and resource-limited environments where digital systems are unavailable or impractical.

Quality and safety considerations include appropriate exposure settings, correct film speed and processing conditions, and adherence to radiographic safety protocols to minimize patient and staff dose and to prevent processing artifacts.