The skin dose of pelvic radiographs since 1896.

OBJECTIVES: To derive conversions of antiquated exposure data into modern equivalents and to apply these in the assessment of the skin dose of pelvic radiographs since 1896. METHODS: The literature 1896-2018 was searched for implicit and explicit dose information. The early implicit dose data contained now obsolete descriptions of radiation quality and quantity for long since disappeared X-ray systems of limited efficiency. Converting the old information into modern specifications was achieved using contemporary data and computer simulations. Final dose calculations were done with modern software. Explicit radiation doses of later date reported in old quantities and units were adapted according to current recommendations. RESULTS: For the period before 1927 conversion algorithms for spark gap data and penetrometer hardnesses to high voltage could be derived. Electrical and X-ray efficiencies of several old röntgen systems were determined. Together they allowed reconstruction of 53 doses. After 1927 doses were generally explicitly specified; 114 were retrieved. Although an enormous spread was observed, the average skin dose was reduced by a factor of about 400. CONCLUSIONS: Antiquated exposure data were successfully used for dose reconstruction. Extreme dose variability was a constant. Efforts to cut down doses were effective as skin doses went down from sub-erythema values to about one milligray.

Early X-ray workers: an effort to assess their numbers, risk, and most common (skin) affliction.

OBJECTIVE: To assess quantitatively the number of early X-ray workers, their risk of becoming a radiation victim, and their most common radiation-induced (skin) disease. METHODS: Information on professional life and occupational disease was retrieved from the Ehrenbuch, a book of honour containing biographies of 404 radiation victims, as well as member and congress lists of the German and US radiological societies, obituaries, books, articles, and the Internet. RESULTS: The estimated numbers of X-ray users in a medical setting in the US increased from about 300 to 600 in 1900-1903, in Germany from about 700 to 1200 during 1905-1908. The risk for a beginning user eventually to die from radiation was 1-2 % in these years, but up to 10-25 % in 1896. Data on 198 victims of fatal radiation-induced skin disease were collected. The incidence of the various stages of skin afflictions with a fatal outcome was characterized by very wide distributions. CONCLUSIONS: After 1896, the radiation risk decreased very fast at first and more slowly thereafter to nearly zero in 1935. Many victims became quite old, partly because of the slower progress of tissue reactions at lower radiation doses, partly because of the success of often multiple surgical interventions. MAIN MESSAGES: US and German X-ray users amounted to several hundreds to thousand in 1900-1908. The risk eventually to die from radiation was about 1-2 % during 1900-1908. After 1896, this risk decreased from >10 % to nearly zero in 1935. The incidence of subsequent stages of skin harm varied strongly in time. X-ray victims could become quite old, dependent on radiation dose and surgery.