Electronic collimation and radiation protection in paediatric digital radiography: revival of the silver lining

In digital radiography we are now able to electronically collimate images after acquisition. This may seem convenient in paediatric imaging, but we have to be aware that electronic collimation has two major downsides. Electronic collimation implicates that the original field size should have been smaller and the child has been exposed to unnecessary radiation. Also, by use of electronic collimation, potentially important information may be lost. The “silver lining”, denoting the X-ray beam collimation, can serve as a useful radiation protection instrument to check for proper field size and detect unnecessary exposure. Furthermore, the silver lining confirms all exposed anatomy is shown in the final image, and thus may also serve as a quality assurance instrument as the patient has the right to all acquired information.