Two years ago, my partner and I purchased 8 headlights to outfit 2 surgery centers and a hospital. We trialed several brands, including tethered and battery-powered models with different types of bulbs. Although I can't say for certain what your docs will look for in surgical headlights, I'll bet these 5 must-haves will be listed on more than a few of their wish lists.

Bright illumination
The intensity or brightness of a headlight is based on how many lumens it generates. It's hard to quantify differences between lumens on paper, so surgeons must assess the brightness of various models during surgery to determine which works best for them.

They must chose between 2 main bulb types: fiber-optic xenon and light-emitting diodes. The early generation of LEDs couldn't match the performance of xenon alternatives, but evolving technology has increased the light intensity of these long-lasting, cooler bulbs. Based on my experience, LEDs maintain their intensity with no perceivable drop off in brightness as compared with xenon bulbs. Why? Perhaps because the brightness of xenon headlights depends on the quality of the fiber-optic cable that connects the headsets to a light source. Fiber-optic bundles within the cable can break over time, causing the light to gradually lose intensity.

I prefer to keep the aperture of our LED headlights fully open during spine surgeries to provide the brightest light across the entire surgical field. Closing the aperture on LED models makes the light more intense, but it doesn't fill the surgeon's field of vision. Closing the aperture on a xenon bulb, on the other hand, will focus the light with laser-like precision, which might be preferred by ENT docs demanding a high level of magnification and intense light.

Natural coloration
Bulbs provide light in varying degrees Kelvin, which impacts the light's perceived color. The higher the Kelvin rating, the whiter the light and the more realistic the color it provides. Incandescent bulbs, for example, produce light at 2,700 ?K. New xenon bulbs provide about 3,000 ?K and fade over time to about 2,700 ?K. LEDs provide light with a bluer hue at 3,000 ?K to 4,000 ?K-plus.

Pay attention to Kelvin ratings when reviewing marketing literature, but all your surgeons will care about is how the light's color renders tissues, nerves and blood vessels so they can differentiate the delicate anatomy. In my head-to-head comparison of xenon bulbs and LEDs, the brighter light provided by LEDs renders tissue more favorably.

COMFORT ZONE There's no adjustment curve with tethered headlights, which some surgeons might prefer.

Cordless comfort
This important factor comes down to whether surgeons prefer working with tethered or cordless headlights. They want to move freely around the OR, but won't surrender light intensity to do it.

Battery-powered LED headlights let surgeons move wherever they want, unhindered by cords. A surgeon wearing a tethered fiber-optic xenon headlight, however, might have to unplug the headlight, move the light source, plug the headlight back in and reposition the headset. He also must worry about keeping the headlight's non-sterile cable from touching or resting on sterile drapes.

Because light sources sit on top of the headlight and various models are weighted differently, surgeons must trial available options to see which have the proper balance when worn during the specific cases they perform. I've heard some surgeons complain that certain cordless models throw off their center of gravity because the light source is integrated in the headset. That's important: Even a slight change to a surgeon's preferred stance can have a huge impact on how he performs during intricate procedures.

A headlight must also mesh with surgeons' loupes so they see with optimal illumination and magnification. It took my partner and me some time to adjust the fit of our cordless LED headlights and some getting used to how they feel. But after a short adjustment curve with respect to how we need to position our heads during surgery, they work for us. In fact, they're so comfortable we hardly notice we're wearing them.

Passing cordless LED models between docs at a busy surgical facility might not be the optimal scenario. Before cases, each surgeon would have to readjust the headlight based on his preferred balance and loupe placement. And surgeons who come to your surgery center once or twice a month might not want to waste time fiddling with cordless models.

Battery life and weight
When it comes to battery life, longer is obviously better. Be sure the combined duration of your batteries — primaries and back-ups — will cover your longest case. The 2 batteries on our units last about 4 hours with continuous use. We have a backup pair charging in case surgeries extend past 4 hours or the primary set dies unexpectedly. When one set of batteries loses its charge, we grab the other set and plug in the freshly drained cells. The rotation ensures we always have a set charged and ready to go.

The higher the amount of lumens a cordless headlight generates, the more power it needs, so the bigger — and heavier — its battery. That could be an ergonomic issue for physicians with lower back problems. Also keep in mind that the lithium batteries that power headlights have limited life spans and will eventually stop holding their charges, so you'll have to budget for replacements, at about $500 each, throughout the life of your headlights.

Some cordless LED headlights can be powered through a thin 12-foot cable attached to a small transformer, in the unlikely event both sets of batteries are unavailable or if surgeons don't want to wear battery packs around their waists. The extended cable is lightweight because it's copper-based, unlike the heavier fiber-optic cables attached to xenon headlights, and offers a degree of freedom around the surgical field.

Durability
Many headlights are guaranteed for 5 years, and most companies provide complimentary loaners if the primaries malfunction and need to be sent for repair. Still, it's probably best to outfit your ORs with enough headlights that you limit wear and tear on individual units, or to invest in enough headsets so each surgeon has his own and is charged with ensuring it lasts.

We've found that tethered xenon models better withstand punishment from constant use, although their fiber-optic cables can break easily, especially if they're accidently run over by a cart or stepped on by a nurse or tech.

It's human nature: You take the best care of the things you own. Would you ever consider asking your surgeons to invest their own money in the headlights they prefer? That's not outlandish to request. In fact, my partner and I purchased our own cordless models that we operate with every week at 3 facilities because we were concerned about durability and ensuring they're properly cared for. We prefer to have them in our possession at all times. They're perfectly adjusted for our balance and loupe placement, so we waste no time setting them up for surgery.

How much would surgeons have to invest? When you factor in the cost of batteries and light sources, cordless LEDs and fiber-optic xenon models cost about the same: $7,000. So in the end, the right choice for them is more about their preferences than it is about cost.