Historically, radiology reading rooms have been undesigned spaces. A typical analog reading room was often simply a large sheetrocked room with fluorescent lights, that could be turned off for peering at the x-ray viewbox. Not so anymore, digital images have brought on new design theories for reading rooms - incorporating ergonomics, lighting, room design and furniture, acoustics and connectivity.
In the early days of the PACS era, a 'deploy it and reap the benefits' philosophy permeated the radiology business. "People thought you could take a computer, throw it on the desk and ask radiologists to sit and read for 10 or 11 hours a day," sums Ric McGill, PACS application manager for University of California Los Angeles Medical Center (UCLA). Environmental factors like lighting, ergonomics and acoustics play a much larger role in the practice of soft-copy reading. For example, comparison between less bright and higher luminance monitors link decreased productivity, decreased accuracy and increased fatigue levels with less bright monitors. Carpal and cubital tunnel syndromes are on the rise among radiologists as are complaints of shoulder, neck and back pain and eyestrain. Throw in the pressure to read more complex cases faster and higher overall image volume and you have the soft-copy conundrum.
Cutting-edge hospitals have revisited and redesigned radiology reading rooms - changing the environment to accommodate and facilitate digital workflow. The aim is to optimize the space for digital workflow and increase comfort, productivity and accuracy among radiologists.
Redesigning a soft-copy reading room is a multi-faceted and complex process. The pieces of the puzzle include lighting, ergonomics, acoustics, room design and spatial enclosures and network connectivity. The process is typically a redesign that reincarnates an analog room as a digital space rather than new construction of a digital reading room. But facilities report that the process is well worth the time and investment as the end result is a truer picture of the PACS environment - a fluid interface between the radiologist and technology that yields increased productivity and decreased discomfort, stress and injury.
Shedding Some Light
Lighting is one of the most critical issues in reading room design, says Bill Rostenberg, San Francisco-based principal with Anshen + Allen, an international architecture firm. Alan Hedge, PhD, director of the Human Factors and Ergonomics Laboratory at Cornell University (Ithaca, N.Y.), agrees. "The key to ergonomics is defining what the job involves. For radiologists, the job consists of pattern recognition with visual images. They have to clearly see images, [which means hospitals] really need to think carefully about lighting for the reading room," explains Hedge.
Many hospitals, however, give little thought to reading room lighting. One common misconception is that the reading room should be dark. Rostenberg points out, "The ideal is a consistent level between the monitor and background surface." The other common pitfall is to rely on traditional fluorescent lighting, which can create reflections and lead to eye strain, headaches and discomfort. Hedge says lighting warrants a level of attention similar to monitor calibration. If lighting isn't standardized, images can look different regardless of monitor quality or calibration efforts.
One starting point for lighting decisions is screen color. The key question to ask is what kinds of images are read in a particular room. Lighting needs differ for monochromatic and color PACS monitors; ideally, hospitals should separate grayscale and color reading areas, says Hedge. Grayscale image reading can be optimized with incandescent lamps with a reasonable amount of blue in the light because cool, blue light helps eyes fix on details. On the other hand, if blue light is selected for color reading of a 3D heart model, normal red blood flow can look more purple and obscure diagnosis. In color viewing rooms, the light source should match images on the screen. The color rendering index (CRI) of the light provides a starting point for light decisions. Bone images, which are more yellow, require more yellow in the light source, while blood images require more red. In general, warmer daylight or triphosphor lights work best in color reading rooms.
Wall color also comes into play. "The color of the light source should match the color of the walls, which should match the color of the screen.