The arrival of high-definition imaging in the OR has been accompanied by an abundance of technical details and marketing jargon that may intimidate you if you're in the market to equip your facility with the stunningly sharp video that HD promises. Here's an examination of some of the issues that commonly confuse potential buyers of HD displays.

What is HD and what is HDTV?
First and foremost, understand that HD and HDTV are not one and the same. While some consumers — and even some vendors — erroneously refer to "HDTV displays," high-definition television is actually a broadcast standard, not a display specification.

While a high-definition display might be HDTV-compatible and able to receive HDTV broadcast signals (although plugging in to them may be of limited use in the OR), HD is the designation you'll want to use on your requests for proposals. That's what indicates that the image resolution is higher than standard definition's 480 horizontal lines of pixels in a frame of video.

It's also important to note that "true HD" and "full HD" are not technical standards, but marketing terms. They're used to describe displays with 1,080 horizontal lines that are progressively scanned (also known as "1080p," in which every line is displayed every time an image is refreshed) as opposed to those that are interlaced ("1080i," which involve a 2-step imaging process in which alternating lines are displayed in each cycle).

How much resolution is necessary?
Given the terms' lack of specificity and the possibility for confusion, you might not even want to rely on "HD," "true HD" or "full HD" to describe the display you're looking for. Seeking out a product by its vertical-by-horizontal resolution (1920 x 1080 progressive, for instance) is a much more precise way of doing business.

HD displays can feature as few as 720 or 768 horizontal lines and still be marketed as high-definition. They're not as costly as higher-resolution displays, but keep in mind that if you invest in displays offering 1,080 or 1,200 horizontal lines — both common configurations in source and display components — you're ensuring you're getting the best quality images.

Let's say you have a 1080p endoscopic camera sending video signals to your display. If the display's horizontal resolution is 720, it will accept the signals but scale them down to the lesser resolution, with an accompanying reduction in image quality. That's just a waste of the money you've spent on the scope. If, on the other hand, your current scopes provide lower-resolution signals, a higher-resolution display will handle those while "future-proofing" your purchase in the event you upgrade your scopes.

A similar logic applies to aspect ratio, the ratio of the image's width to its height. Since the latest scopes employ the widescreen, 16:9 format, you may want to consider buying a widescreen-capable display, even if you have older scopes that present images in the squarer 4:3 or 5:4 formats. The widescreen displays can still read their images.

Make sure, however, that the resolution you choose is specified as the display's "native resolution." As mentioned above, HD displays with horizontal resolutions of 720 or 768 can accept higher-resolution signals, but they just won't show them at their original quality. If the native resolution of the display matches that of the source, however, you're guaranteed the best possible image.

Do "medical grade" displays provide better images?
The short answer: No. As applied to video equipment, the designations "medical grade," "surgical grade" or "hospital grade" don't signify a higher image quality — there is no high-definition standard for medical video that corresponds to commercial broadcasting's HDTV — but rather that the equipment meets all safety requirements for operation in a surgical field.

For electrical safety, medical grade displays typically operate on a lower voltage than conventional displays do, powered by 24 volts instead of the customary 120, and are equipped with an external power converter to make that change.

From an infection control standpoint, they feature low-heat operation, since anything that generates heat will attract dust, and as a result are built without the fans and vents that can disperse dust. They also have cleanable surfaces in the event that they're splashed or spattered during the course of a case.

Medical grade displays can be more expensive than conventional displays, but their safety features are required if plans call for boom- or cart-mounted video components in the surgical field. For displays that will remain outside of the field, however, conventional monitors are acceptable.

Can you compare or trial displays?
When flat panels replaced bulky cathode-ray tubes as the mainstream choice for surgical video output, liquid crystal display (LCD) became the de facto standard for display technology. Household buyers face a choice between LCD and plasma televisions, but there's no such divide in the surgical market.

Plasma displays were once available for ORs, since they were available with larger screens for wall-mounting than LCDs were. But they generated more heat and used more power, and unconfirmed reports emerged that they produced and received electromagnetic interference when operated in conjunction with other medical equipment. Now, however, LCD displays are available in comparable sizes, and are the only option for medical grade displays.

It's not easy to trial displays in the same way you might compare OR lights, surgical tables or other equipment. Given the resolution specifications, there is not that much of a difference in their output. Think about the last time you went into a store where the HD televisions were lined up, side by side, on the wall: Could you tell them apart?

Often it's simply an issue of the screen size you want and the price you can afford. As long as you're purchasing the resolution you want, there's no reason to spend a lot of money on a wall-mounted display that will be at a distance from the surgical team. As far as surgical field displays are concerned, the closer you are, the smaller they can be, since the image presented on a large screen may be difficult to fully observe at close range. Larger displays mounted on booms also present a greater risk of equipment collisions.

Where can I buy displays?
For many surgical facilities, the purchasing decision is automatic. Whoever sold you your endoscopes or your OR integration system can also supply you with displays for viewing the output. If you're in the market for medical grade displays, it may make sense to go to your source and distribution equipment vendors for them.

But if medical grade isn't required, if you're shopping for a wall-mounted display for instance, you might want to consider visiting your local "big box" stores or checking out online electronics retailers. The HD video displays available to consumers for home entertainment are often identical to the models sold to medical professionals — note the model numbers when you're reading vendors' proposals or dropping by the electronics department — and can save your facility a fair amount of money, especially if you're buying in volume.

Take any statements that you've got to buy from your equipment vendor for compatibility's sake with a grain of salt. Outside of medical grade equipment, video displays all meet the same standards. As long as the model you buy has input jacks for DVI and HD-SDI, the types of cabling required to carry high-definition signals, they're adaptable to any vendor's equipment.

If you choose to buy from an outside retailer, though, don't neglect the service contract. As with any capital purchase from a specialized medical vendor, you'll want to arrange some sort of protection against the costs of repair and maintenance should your display fail to function. Whether you're buying from a medical vendor or a consumer retailer, budget about 10% of the cost of the item each year for service plan coverage.

Ampronix
Medvix Surgical Displays (800) 400-7972 www.ampronix.com
List price: Ranging from $1,853.33 to $11,000, depending on screen size and options. FYI: Available in a range of screen sizes from 15 inches to 52 inches. Provide clarity, brightness, high contrast and a wide viewing angle, says the company. Select models offer full HD support and HD-SDI input for images in 1080p resolution, and select models feature an antibacterial-treated enclosure to safeguard the equipment against bio-deterioration.

Barco
MD-4221
(866) 360-3545
www.barco.com/medical
List price: $8,299
FYI: This 42-inch full high-definition (1920 x 1080) monitor is designed for and certified for use in the digital OR. The versatile display can present a wide range of analog and digital video sources in fine detail, including HD endoscopic video, room and boom camera video, patient and surgery information, radiology and pathology images, says Barco.

NDS Surgical Imaging
Radiance With Full MMI
(408) 776-0085
www.ndssi.com
List price: not disclosed.
FYI: MMI stands for Multi-Modality Imaging. This feature lets you view any 2 input sources simultaneously, on the same display, in split-screen or picture-in-picture configurations. Available in a range of screen sizes and able to support 2 DVI inputs as well as 2 HD-SDI inputs to offer unprecedented flexibility for HD digital video connectivity, says the company.

NEC
MultiSync MD Series
(866) NEC-MORE
www.necdisplay.com
List price: $3,899 to $4,999
FYI: These diagnostic flat panel displays, designed specifically for medical imaging, radiology and PACS, offer high brightness without compromising an image's contrast or adversely impacting users' viewing angles, says the company. Available in color or grayscale LCD, the displays feature digital correction to reduce screen uniformity errors and to compensate for differences in color or grayscale representation and luminance across the entire screen. NEC offers standard 3- and 5-year warranties and overnight exchange.

Olympus
OEV261H
(800) 848-9024
www.olympusamerica.com
List price: not disclosed.
FYI: This 26-inch monitor features full HD, a 16:10 aspect ratio, a high-contrast ratio, wide-angle viewing, and inputs and outputs for Y/C, RGB and WUXGA. With 10 pre-selected settings and 20 user-selectable settings, images captured by Olympus's HD endoscopes are presented with the best quality color tones and display sizing, says the company. Additional features include multi-modality capability, picture-in-picture, image rotation and mirroring.

Richard Wolf
Medical Instruments Corporation
26-inch Flat HD Panel Monitor
(800) 323-WOLF
www.richardwolfusa.com
List price: around $7,500
FYI: This 26-inch, flat-panel, HD display (pictured here with the company's Pro Series Video Cart and 5500 Autoclavable HD Camera System) is compact and lightweight enough for boom-mounting as well as adaption to existing GI and surgical video carts, says the company. 1080p resolution offers precise and brilliant images and its widescreen, 16:9 format enables optimal viewing at this resolution.

Sony Electronics
LMD-3250MD
[email protected]
sony.com/hdforsurgery
List price: $7,495
FYI: The latest addition to Sony's line of medical grade LCD displays, the LMD-3250MD features a 32-inch screen, widescreen format and 1920 x 1080p resolution to enable the pure reproduction of images captured by the latest full HD surgical cameras. Its 10-bit panel driver, 10-bit signal processing and Sony ChromoTRU color balance technology deliver high performance imaging, says the company, and its smaller power supply enables easier OR integration.

Steris Corporation
24- and 26-inch Surgical Grade Flat Panel Monitors
(800) 548-4873
www.steris.com
List price: $12,995 for the 24-inch display, $14,995 for the 26-inch display.
FYI: High brightness and contrast without glare, a 16:10 aspect ratio, multiple window viewing options and customizable user presets. Engineered with 1-touch access to menu navigation and 8 video inputs for easy switching of OR equipment. They can support all progressive video formats (480p, 720p and 1080p) as well as the most common camera signals (including DVI, SDI, RGBHV and S-video), which enables compatibility with cameras from many other manufacturers, says the company.

Stryker Endoscopy
WiSe HDTV Surgical Display and Transmitter
(800) 435-0220
www.stryker.com/endoscopy
List price: not disclosed.
FYI: The 26-inch display, combined with the WiSe HDTV Transmitter, channels uncompressed 1080p signals without cable clutter and a reduced risk of costly repairs to flat panels, says the company. Token keys create unique codes between the display and transmitters to protect the wireless signal from interfering with other equipment. This technology gives you the freedom to move the display anywhere in the OR.