Technical Factors and Exposure Indicators

摘要

Reducing unnecessary radiation exposure to patients is an ethical obligation outlined in the profession's Code of Ethics. Having a good working knowledge of exposure indicators provides technologists the ability to adjust technical factors in a way that will reduce patient exposure while maintaining high image quality.Image receptor (IR) exposure levels affect image quality. IR exposures that are too low, for example, produce images of limited diagnostic value because noise in the form of quantum mottle obscures image recolu-tion. IR exposures that are too high increase patient dose unnecessarily and can sometimes render digital imaging systems unable to erase images completely, resulting in a ghosting artifact on subsequent exposures (see Figure).