The Dome C3 Dual medical-grade, 3-megapixel, 20.8-inch AMLCD monitor from Planar Systems Inc (above) displays 3,061 shades of gray and offers a contrast ratio of 600:1, a viewing angle of 170? horizontal and vertical, and a luminance of 700 cd/m2.

Even after 21 years in the business, Planar Systems Inc (Beaverton, Ore), the world’s number one provider of flat-panel displays for medical applications, still has the power to wow the market. And that’s just what the $250 million company did in February by announcing it would slash prices of its Dome line by nearly 50%, effective immediately.

“We’re recognized as product leaders,” explains Matt Harris, VP of marketing and corporate development for Planar. “We want to be product leaders and price leaders. Hardware makes up a significant portion of the cost of rolling out PACS, and we want to make it easier for hospitals to afford the best displays for PACS.”

Harris attributes the price cuts to an efficient supply chain that helped Planar reduce costs, but others are quick to underscore the importance of growing competition.

“Before we entered the medical display arena, there were few players,” says Madhu Reddy, president of US Electronics Inc (USEI of Minneapolis), “Planar and Barco set the tone for high markups and a high overall price structure. Now, with USEI’s presence, growing competition is bringing prices down.”

A relative newcomer to the market, USEI entered the medical arena in 1996, distributing monitors from Totoku North America Inc (Irving, Tex) primarily through system integrators and resellers. Now it’s competing head to head with Planar.

“Our products are very high performance, but we’ve been able to eliminate unnecessary electronics by simplifying the design and using high-tech chips,” Reddy says. “USEI has brought new, affordable pricing to the market.”

You might expect the competition to be up in arms about price wars, but that doesn’t seem to be the case.

“It’s certainly changed the dynamic,” muses Marta Volbrecht, executive VP of Image Systems Corp (Minneapolis). She explains that Barco started offering a low-cost product with fewer features, but Planar’s low-cost products have retained the full array of features.

“It’s creating new opportunities,” Volbrecht says. “The technology envelope is being pushed, offering more technology at a lower price. The focus will be on bundled solutions, ease of use, and hands-free calibration.” Image Systems’ strategy, for example, includes adding hands-free features with minimal price increases. The company sells its monitors through distributors that are able to offer the service and support that Image Systems is unable to provide outside the Minneapolis area.

 The 21.3-inch NEC LCD MD 21GS-3MP (front) medical-grade monitor from NEC-Mitsubishi shows 3,061 shades of gray and offers a contrast ratio of 700:1, a viewing angle of 170? horizontal and vertical, and a luminance of 800 cd/m2. The company’s 21.3-inch NEC LCD MD 21C-2MP medical-grade color monitor (back) offers 8-bit RGB, a contrast ratio of 500:1, a viewing angle of 176? horizontal and vertical, and a luminance of 250 cd/m2.

“When NEC-Mitsubishi entered the medical-display category, we set out to improve the user experience by introducing innovative technologies that effectively raise the bar for the industry in the areas of performance, image quality, and ease of use,” says Todd Fender, senior product manager of medical products for NEC-Mitsubishi (Itasca, Ill). “Having recognized a lull in the advancement of display technology, we took the reins from our competitors and proceeded to drive the market with our progressive medical products.”

Another surprise from Planar is its decision to distribute the low-cost models through consumer computer giant Dell—a move that’s raised eyebrows from industry insiders. In essence, Planar is creating a new channel for its entire Dome line of displays for digital imaging. Planar recognizes that hospital IT managers would like to buy more of their hardware from IT channels that they know and trust, and the company is helping them do just that.

Volbrecht, however, believes it could be a mistake to push medical-grade monitors as a commodity product. In an industry where products differ only slightly, Image Systems is emphasizing customer service and support. Such elements are crucial in an environment of rapidly evolving software.

“Dell can fix a PC better than anybody else, but are they going to go back and do something to fix [the monitor] if it’s not compatible?” Volbrecht asks. “Can Dell deal with fundamental changes when it comes to software revisions? Will the company want to do all that?”

LCD versus CRT
Questions are rife as an industry settles in on its new standard: Cathode-ray tube (CRT) monitors are disappearing as liquid crystal display (LCD) technology gains a solid foothold.

“A lot of CRTs are still in place,” says Bill Greenblatt, VP of sales and marketing for Quest International Inc (Irvine, Calif). “They’re good for people who are on a budget. But an LCD is so much better, it’s almost a no-brainer.”

Almost. Jim Lindsay, international sales manager for Ampronix Inc (Irvine, Calif), indicates that high-end CRTs aren’t being manufactured as much, and Volbrecht acknowledges that Image Systems’ CRT business has picked up as other manufacturers have left the niche. However, Volbrecht is quick to point out that some modalities still require CRTs.

LCDs haven’t yet met the needs of the cardiac catheterization lab, where response time—or refresh rate—is the top priority. CRTs still have the edge on refresh rates. And because many CRTs were installed only a few years ago at a cost of hundreds of thousands of dollars, such users will likely keep these CRTs in place for a long time.

But don’t write LCDs out of cath labs for good. “LCDs are replacing CRTs,” Lindsay says. “Total cost of ownership is much less on an LCD over the long run. The image quality is better because it’s a true flat panel. There’s no image deterioration at the edges of the display that is inherent on the CRTs because of the shape of the tube. They don’t generate as much heat, and they don’t take up the space of a CRT. A 5-megapixel LCD, for example, weighs about 25 lbs and takes only about 15% to 20% of the space. The CRT weighs about 85 lbs and takes up the whole desk.”

And according to Fender of NEC-Mitsubishi, response times are getting quicker, and color representation is improving. “With LCD technology came things you couldn’t do before,” he says. “It has a slim footprint, there’s less power consumption, and there’s no magnet in the back to interfere with diagnostic equipment.

“The inherent problems in the technology from 5 or 6 years ago are no longer there,” he continues. “For digital imaging, the LCDs are just as good and don’t require the costly calibration checks needed for CRTs.”

USEI’s Reddy agrees. “LCDs are so stable, there’s no need,” he says.

High Price of Making the (Medical) Grade
As LCDs have soared in popularity in the consumer market, many medical consumers fail to grasp the difference between medical-grade monitors and comparable models on sale at the local computer store.

“They’re not seeing any difference,” Fender says. “Yet the cost can be four times as much.”

 The AMM20TDG-5M medical-grade, 20.1-inch, LCD monitor from Advan International Corp offers 24-bit color, a contrast ratio of 600:1, a viewing angle of +/- 85? horizontal and vertical, and a luminance of 850 cd/m2.

With hospital budgets being stretched in every direction, it’s easy to see why some opt for the less expensive consumer-grade monitors. Mark Lutvak, head of sales and marketing for Advan International Corp (Fremont, Calif), cringes when he talks about it.

“Hospitals will buy a flat-panel at Staples and put it near a patient,” says Lutvak. “And they might not have any problems until the FDA comes in. You assume the risk of losing your hospital’s accreditation. And remember, those FDA audits are unannounced.”

The FDA requires that any electronic device used within 2.5 m (about 10 feet) or less of a patient must have UL2601 certification. The units are more tightly designed in the areas of electrical isolation, radiation immunity, and resistance to moisture. But the cost of meeting UL2601 and additional FDA standards is significant and must be passed on to healthcare customers.

“In order to get those certifications, extra things must be designed and then added to the unit,” Lutvak explains. “The manufacturer also must pay for those additional regulation marks or approvals. It can cost more than $100,000 per model for all those certifications.” He acknowledges that customers don’t see Advan’s trademark very often, as most of the company’s monitors are sold through OEMs under private labels rather than directly to hospitals.

 The Coronis 5MP medical-grade, 21.3-inch, flat-panel monitor from Barco (right) offers a resolution of 2,048 x 2,560 (5 megapixels), a contrast ratio of 600:1,a viewing angle of 170? horizontal and vertical, and a luminance of 700 cd/m2.

FDA regulations are only a part of the difference of medical-grade units. The panels themselves are held to a higher standard in medical applications, where what would be considered a negligible glitch in another environment could mean the difference between life and death.

“The quality level at consumer retail is nowhere near what healthcare needs in order to ensure a safe and accurate diagnosis,” Lutvak says. “Inherent in many of the retail monitors is a problem with excessive dead or missing pixels, which certainly are OK for PC desktop applications, but not when you are diagnosing patients. With consumer-grade flat panels, you get either excessive—say, 20 to 50—brightly colored spots on the screen or a black hole. If that happens on an organ that’s being studied and you misdiagnose, that’s a problem. And it often happens with consumer products that are not intended for diagnostic use. I do not think that is a risk the hospital or physician is willing to take.”

Manufacturers, of course, are unanimous: The lower prices aren’t worth the risk.

Desperately Seeking Standards
Resolution requirements vary by modality, but even then it’s a matter of price and preference, not mandated standards. Resolution means the number of pixels that a monitor can display. A 3-megapixel monitor, for example, displays 3 million pixels.

“Until the American College of Radiology has identified standards, it’s not up to us to tell the doctors,” Greenblatt says. “We provide the information and let them decide.”

Consensus requires 5 megapixel units for mammography, but that’s where the agreement ends.

“A variety of different things are available, and your application will determine your needs,” explains Lindsay of Ampronix. “A lot of people think they need very high resolution when they don’t, and vice versa. Color panels aren’t recommended for diagnostic use, but we see them used that way. There haven’t been any real standards set by the radiological societies. Nobody’s come out and said, ‘This is what you need for this application.’ Some applications, such as CT, MRI, and ultrasound, don’t need the high-resolution panels, which of course are more expensive. You definitely need to go up to the 3- or 5-megapixel range for some applications—like mammography, where 5 megapixels would be the choice.”

The Gray Area
Color monitors have certainly gained in popularity, but most modalities still rely heavily on grayscale monitors. Gray scale refers to the number of shades of gray represented per pixel.

“Nuclear medicine needs color, and certain CT applications are using color at this point,” Lindsay says. “Those don’t necessarily require a really high-resolution panel in order to make a diagnosis. The resolution is inherent in the equipment they’re using, so getting by with a 1,600 x 1,200, 2-megapixel display would be fine.

“Brightness and contrast ratios are much higher in gray scale,” he continues. “There are big differences both in the construction of the panel and in the controller card that they’re packaged with.”

In other words, not all grayscale monitors are alike.

“An important thing about grayscale displays is the ability to output 10 bits, with a minimum of 256 shades of gray,” says Lynda Domogalla, marketing manager of medical imaging products for Barco (Kortrijk, Belgium). “The human eye can perceive more—somewhere around 700 just-noticeable differences. We can display 1,024 shades of gray.”

Many companies tout a large gray scale, Domogalla says, which is meaningless if it can’t be displayed simultaneously. “It’s really confused the market,” she adds.

 The ME511L medical-grade, 21.3-inch, LCD monitor from Totoku Electric Co Ltd (right) provides 11-bit displayable gray scale and offers a contrast ratio of 600:1, a viewing angle of 170? horizontal and vertical, and a luminance of 750 cd/m2.

Sellers also extol their high video response times (ie, the length of time it takes for a pixel to go from black to white). But be careful about those numbers, too, because they might not represent an average, warns Herb Berkwits, Totoku product manager at Quest International Inc. It might take a panel longer to go from one shade of gray to another than it does to go from black to white.

But playing the numbers game isn’t the only way to determine the best quality. “Use your eyes,” Berkwits recommends.

Features Galore
Aware that their products are tough to differentiate, manufacturers across the board are latching on to the added features that their customers crave. Among the most important are remote monitoring and calibration.

“A customer with 50 workstations wants to be able to calibrate them from a central location,” Lindsay says. And calibration is everything.

Quest’s Greenblatt concurs, adding, “If the monitor isn’t calibrated properly, you’re not seeing what you think you’re seeing. We precalibrate the monitors, and they remain calibrated.” That saves users time and eliminates the requirement for specialized tools and technology.

Planar’s Dome C2, C3, and C5i diagnostic imaging displays, like most premium displays on the market, include a systems-monitoring package that automates the calibration process and frees users to perform diagnostic reads with confidence. This software also can be managed across the enterprise by QA departments or service providers.

“With the Internet accessibility of PM Medivisor [USEI’s remote monitoring software], PACS administrators who are traveling or who manage systems in various locations can do so from anywhere in the world,” Reddy explains.

Barco’s MediCal Pro is configured to perform calibrations and quality assurance functions in the background while the user continues working. The system is optimized with Barco’s I-Guard sensor, which is tucked in the lower-right corner of the screen.

“Other sensors can see only the backlight,” Domogalla explains. “They don’t see ambient light conditions, the panel glass, or the effects of the LCD itself, which will darken and turn brown over time.”

NEC-Mitsubishi’s NEC-MD series, due out this summer, is designed with control buttons on the back and a backlight technology called X-Light. This stabilization technique ensures consistent brightness.

“A patent-pending technology will allow us the ability to control the color of the backlight,” says Stan Swiderski, senior product development engineer for NEC-Mitsubishi. “We can match two monitors side by side, or we can have blue- or clear-based monitors. The choice between blue and clear base is partly a matter of preference, and each has strengths in specific modalities.”

The Brightness Factor
“People like bright panels,” says Lindsay of Ampronix. “That’s not necessarily optimal. You don’t want it cranked up all the way on brightness, because the heat from the backlight causes things to age, and it shortens the life of the panel.”

Backlight life span is another important factor in displays, and some companies proffer hefty promises.

“That’s a number you have to be careful about,” Domogalla advises. “How long can you maintain it at a calibrated luminance? Our DuraLight backlight will last as long as the LCD—actually longer.”

And that’s nothing to sneeze at, when you consider that backlights are expensive to replace, and the replacement must be done in the factory.

Totoku’s newest monitor—the ME213L, distributed by Quest—is scheduled to launch this month, with a maximum luminance of 1,500. Typical grayscale monitors produce a maximum luminance of 700 to 750. The new monitor can still be used accurately in a brightly lit room if need be.

“At RSNA 2003, others had to put canopies over their displays,” Greenblatt notes. “When you’re going into an ER or an OR with a higher level of ambient light, you need a brighter screen.”

Keeping the brightness cranked to that level demands a trade-off of backlight life, of course, but the backlight is designed to last for 100,000 hours of use—about 10 years.

 The FP1800CMAX medical-grade, 1.3-megapixel, 18-inch monitor from Image Systems Corp (above) offers 24-bit color, a contrast ratio of 300:1, a viewing angle of 80? up/down/left/right, and a luminance of 210 cd/m2.

If the PACS Fits …
DICOM-compliance also is vital, and monitors interface with PACS differently. Image Systems’ Volbrecht believes her company’s model maximizes functionality because it makes its own display, controller card, and calibration components and then tests them with BRIT Systems (Dallas) and other PACS providers.

“As companies change software, you need to keep the hardware in mind,” Volbrecht admonishes.

NEC-Mitsubishi’s Swiderski adds, “Most medical monitor manufacturers don’t manufacture the LCD modules that the monitors use. They have someone else build them to spec. One of our sister companies manufactures our LCD modules, so we have access to the core technology. We have a dedicated research and development department. We can make the module better knowing how it was built and understanding the components.”

A Supporting Role
Just as the medical milieu requires more from its machines, it also requires a higher level of support. Critical services can grind to a halt if equipment failure isn’t addressed immediately. Planar, for example, provides 24-hour phone support and an express replacement service that delivers equipment overnight.

Each seller has its own support standards, and that’s an important feature to compare when you’re choosing a monitor.

And once you create your shopping list of features, simply keep Berkwits’ advice in mind: Use your eyes.

How high is too high tech?

by Herb Berkwits

One of the errors often made by radiologists and imaging centers is to use a standard desktop monitor for primary reads. How does a medical LCD monitor differ from a consumer-grade LCD monitor? Consider these five factors when purchasing your next monitor.

Calibration. The established gamma response curve for medical devices is set by DICOM Standard 3.14. This curve is designed to take the human visual system into account and to provide more information at the dark end of the scale. To match this curve, it is necessary to have a display palette greater than the number of shades of gray to be displayed. Whereas consumer LCD monitors can display only 256 shades of gray, medical monitors can display up to 12-bits (4,096 shades) of gray scale. The more shades possible, the more accurately the DICOM curve can be fit, and the more accurate the image can be displayed.

Contrast Ratio. Just because a monitor is bright does not make it a medical-quality display. It also must be able to display shades of gray at the dark end of the scale. Consumer monitors have contrast ratios of around 250:1 to 350:1. Most panels used for medical displays have a contrast ratio greater than 500:1. The ME201L from Totoku North America Inc (Irving, Tex), for example, has a contrast ratio of 1,000:1.

Luminance. Consumer-quality desktop monitors use color LCD panels with a maximum luminance of 200 to 250 cd/m2. Medical displays are typically gray scale (monochrome) with a maximum luminance of 650 to 750 cd/m2. This greater dynamic range is necessary to provide a full 8-bit gray scale, or 256 distinct shades of gray.

Safety. If a monitor is to be used in patient proximity, it must be designed to have a very low leakage current to ground from the power supply; otherwise, there is the risk of a shock or detrimental effect on life-sustaining devices, such as pacemakers. Underwriters Laboratories Inc (Northbrook, Ill) certifies medical monitors to a specification called UL2601, whereas consumer monitors are only held to UL1950 for office equipment and are permitted much higher leakage current.

Stabilization. The LCD backlight varies in luminance over time and temperature. It can take a consumer-grade LCD monitor up to 90 minutes to stabilize after being turned on, so even if this monitor could be calibrated, it would not meet the standard for more than an hour. Medical LCD monitors have additional circuitry that brings the backlight to its calibrated luminance quickly (often in less than a minute) and maintains it there over time and temperature modulation.

Herb Berkwits is the Totoku product manager for Quest International Inc (Irvine, Calif).

Holly Celeste Fisk is a contributing writer for Medical Imaging.