LCD monitors can produce enterprise bliss

September 30, 2003

For those struggling with what sort of monitor to use when distributing medical images throughout the enterprise, consumer-grade LCD monitors may provide the solution. The PACS vendor usually offers little guidance on hardware and monitor configuration

For those struggling with what sort of monitor to use when distributing medical images throughout the enterprise, consumer-grade LCD monitors may provide the solution.

The PACS vendor usually offers little guidance on hardware and monitor configuration across the enterprise, especially if the vendor employs a thin-client distribution model. Medical-grade monitors are too expensive and their benefits can be negated by the high ambient lighting conditions typical in enterprise locations. At the other end, many hospitals go for the cheapest monitors they can find, but this can cause a backlash when the clinicians compare what they are getting to what radiologists use.

The answer: a new line of commercial off-the-shelf 2-megapixel 21-inch liquid crystal display (LCD) monitors with the ability to pivot into a vertical orientation.

The vertical orientation is key. Vertical, or portrait, positioning has long been preferred by radiologists because most anatomy has a vertical aspect ratio. A vertical aspect ratio provides better utilization of the real estate on a screen that also contains buttons and menus. Images can be displayed at a higher enlargement than with landscape monitors.

Now that the commercial LCD monitor has been widely adopted and surpassed the cathode ray tube in popularity, prices are coming down. The new batch of 21-inch LCD monitors can be purchased for $1200 to $1500. If that price is too much for your budget, smaller and less expensive portrait monitors are available. I found a 2-megapixel 19-inch portrait LCD for around $900 and even a 1.2-megapixel 17-inch portrait LCD for $600.

Since these monitors are in the commercial market, expect the prices to continue to drop at least 30% to 40% per year.

Rotating the image to a vertical orientation is actually a software trick. In theory, you can flip any monitor on its side and convert it into portrait mode. Higher end LCDs make it easier for you by including the software and a swivel base, which facilitates rotation. Twenty-one-inch portrait LCD monitors look very similar to the diagnostic medical monitors in size and appearance, while also providing enterprise users with color for other applications.

The relatively high resolution of 2 megapixels will provide good quality for CR images without requiring much image manipulation. The commercial LCD monitors that I looked at have a luminance of 250 candelas per square meter or 73 foot lamberts, levels that are better than most commercial CRT monitors. LCD monitors also have a much smaller footprint than CRT monitors.

To ensure the best performance from an LCD monitor, use a digital video interface (DVI) adaptor as opposed to a standard analog VGA adaptor. The DVI adaptor preserves the digital signal, while the VGA adaptor sends the monitor an analog signal that must then be converted to digital.

If your budget permits, you can even set up dual monitors. If you want to use these monitors for diagnosis, tools are available that will calibrate the display to the DICOM display function.

If you want to win over the enterprise, look closely at this technology. You are unlikely to see the same level of griping that you might get from landscape or CRT monitors. We went this way at our institution, and the result was some griping - not from clinicians but from radiologists who complained because they were required to read images on landscape-oriented medical CRT monitors.

DR. NAGY is director of the Radiology Informatics Lab at the Medical College of Wisconsin and the editor of ClubPACS, a Web-based source of PACS information. He can be reached by e-mail at PNagy@mcw.edu .

References on LCD monitors

Commercial LCD calibration system to DICOM display function
Http://www.image-smiths.com

LCD - For the Novice and the Expert
http://www.anandtech.com/showdoc.html?i=1855

How LCDs Work
http://electronics.howstuffworks.com/lcd.htm

Review of the Samsung 21" LCD
http://www.gamepc.com/labs/view_content.asp?id=samsung213t&page=1

Review of the planar LCD
http://www.gamepc.com/labs/view_content.asp?id=planar17&page=1

Review of the Philips 17" LCD
http://www.gamepc.com/labs/view_content.asp?id=philips17wide&page=3