Dutch researchers fired up a 115-year-old x-ray machine, comparing its image quality and radiation dose with current technology. They found that the vintage system delivered a radiation dose that's 1,500 times the level of modern x-ray systems.
Despite the higher dose, the researchers said they were impressed that investigators in 1896 -- just a month after Wilhelm Conrad Röntgen's discovery of the x-ray -- were able to build an x-ray machine with parts found in the inventory of a local high school and acquire images that clearly demonstrated human anatomy.
Early x-ray machine developed by Hoffmans and van Kleef.
All images courtesy of the Radiological Society of North America.
The machine was based on the use of Crookes tubes, glass cylinders that generate electrons when voltage is applied.
Early radiographers might have been frustrated with the throughput of the vintage unit: The researchers found that they needed 90 minutes to acquire a hand image, compared with approximately 20 msec for the modern radiography system. What's more, Kemerink and colleagues characterized the x-rays produced by the system as "soft," due to a lack of filtration and other factors.
Images of the hand specimen of an 86-year-old woman obtained with vintage x-ray machine (left) and a modern x-ray system (right). The exposure time with the 1896 system was 21 minutes.
The researchers noted that the high radiation levels produced by early radiography systems often resulted in severe injuries to equipment operators. Health problems reported shortly after Röntgen's discovery included eye complaints, skin burns, and loss of hair. Many operators also experienced severe damage to their hands over time, which sometimes required amputation.
The lead author of the study was Martijn Kemerink, PhD, of Maastricht University Medical Center (Radiology, May 2011, Vol. 258:5)
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