Q+A CENTER

We’ve come a long way since the early days when x-rays were sent through a particular area of the body directly onto a piece of film, often requiring several minutes of exposure. Today’s digital technology can do it in seconds. How we view x-rays, CTs, PET (positron emission tomography) scans and the like also has changed since German physicist Ferdinand Braun created the earliest version of the cathode ray tube in 1897.

High-resolution displays are, of course, a vital tool in diagnostic medicine. They long have been grayscale, but that’s changing. And the key to the change is illumination.

“Grayscale has been around a long time, since the CRT days. Color technology has caught up to grayscale,” says Stan Swiderski, Business Development Manager, Professional and Medical Displays at NEC Display Solutions of America (Itasca, Ill.).

“In the past, you couldn’t just put more light behind the color because the contrast ratio would go down. Now, you can have color with the proper contrast ratio with brightness of 400-500 candela. The ACR [American College of Radiology] requires a minimum of 172, but due to market conditions, 400 is considered the norm.”

Lynda Domogalla, Market Director, Diagnostic Displays and Director of Product Marketing for Barco, agrees. “Traditionally, x-ray has been grayscale. Color has lower-resolution displays, but we’re seeing more modalities that use color, like ultrasound. With improvements in CT, where they are getting more and more slices, they can go to a 3D model and use color. PET combines grayscale with nuclear [imaging]. There’s a need for both resolutions.