HELP WELCOME Computer guidance adds an additional layer of safety during difficult cases, says Nathan E. Nachlas, MD.

One surgeon describes the area of focus for ENT specialists as 'high-priced real estate' that includes or borders on many critical anatomical features — the eyes, the brain, the olfactory nerve, the tear duct — that can easily be injured. With so much at stake, and so little room for error, precision and safety are paramount for otolaryngologists. Before the advent of CT image guidance, surgeons couldn't be as thorough as they'd have liked, says Keith Matheny, MD, FARS, who practices at the Baylor Medical Center in Frisco (Texas). 'We just didn't know exactly where we were in relation to those important structures,' he says. Dr. Matheny believes image guidance 'is a breath of fresh air,' because anatomical features don't just vary from person to person, they often vary from side to side in the same person.

Convenience and efficiency are also key considerations. How long does the system take to set up and calibrate? How do systems overcome line-of-sight issues? What kind of OR footprint do they have? What additional benefits are gained via computer guidance? The 5 latest navigation systems offer a package of benefits that address all of the above.

Brainlab Kick EM
The Brainlab Kick EM's versatility is a big selling point for David Edelstein, MD, chief of otolaryngology at the Manhattan (N.Y.) Eye, Ear, and Throat Hospital. 'The beauty of it is that once you learn how to attach the equipment, you can attach any equipment in a set — as long as it's calibrated,' he says. With some other systems, surgeons are limited to one right-angle suction device, 'but I have about 8 different versions of right angles depending on the patient, and I can use any one of them.' Calibration is done with a small laser device, which is another positive, says Dr. Edelstein. 'I don't have to touch the patient's face or skin, which I don't really like to do.'

It's also a planning device — 'A wonderful tool before the surgery,' says Dr. Edelstein. 'People sometimes forget this, but before the surgery I'll run through the entire anatomy 3-dimensionally (using coronal, axial and sagittal views) and look at the areas that I consider to be a challenge or dangerous. For example, one side of the nose may not be a perfect image of the other side of the nose. I'll make a note of that. It helps me review and enhances patient safety.

'It's a fantastic piece of equipment,' he adds. 'It's easy to use, it's straightforward, and the staff can set it up easily. It makes a good surgeon better.'

Fiagon Navigation System
Fiagon's Navigation System uses an electromagnetic tracking system to locate surgical instruments during an operation relative to a patient's CT scan. A recent addition to the U.S. market, Fiagon offers a literal flexibility other systems don't have. Instead of relying on a handle-based tracking system, its 'chip on the tip' technology lets surgeons bend instruments without compromising navigation. That, says the company, reduces risk and shortens operation times by reducing instrument exchanges. 'The (FlexPointer 1.5) instruments are malleable because the sensor is in the tip,' says Martin J. Citardi, MD, FACS, chairman of the department of otolaryngology at the University of Texas McGovern Medical School at Houston. 'That's an advantage.'

The small-footprint system also includes a micro-sensor guide wire that can pass through other instruments and provide continuous monitoring of the wire tip location. 'Navigation on the spot,' the company calls it. That can help with the accurate placement of, for example, balloon sinuplasty devices, says Dr. Citardi.

Karl Storz NAV1
Karl Storz's newest entry offers several attractive features, says Dr. Citardi. For starters, instruments are equipped with reflective glass spheres that can be autoclaved, so they're reusable. 'Most systems have a fairly significant disposable cost-per-case,' says Dr. Citardi, 'so there can be some distinct advantages to having reusable instruments.' Storz also offers both infrared- and electromagnetic-based systems, depending on surgeon preference. The system footprint is also smaller than most, with a tablet-sized screen that can be attached to a standard pole. 'It's very slick and portable,' says Dr. Citardi.

In a specialty in which manufacturer support can be a challenge, Dr. Citardi says Storz' reputation for reliability is also comforting. 'Traditionally, Karl Storz always has well-thought-out, well-executed, well-engineered systems with a high degree of reliability baked in,' he says, 'and traditionally, their sales force has been well-trained. I think they'll be able to support this system well.'

NO OBSTACLES Line of sight is never an issue with his preferred system, says Keith Matheny, MD, FARS.

Medtronic Fusion
The Medtronic Fusion's computer-assisted balloon sinuplasty capability is one of several key features that attract Nathan E. Nachlas, MD, co-chairman of Ear, Nose and Throats Associates of South Florida in Boca Raton.

'It adds an additional layer of safety to the procedure during difficult cases,' says Dr. Nachlas. 'I hear people say they don't need computer guidance, they know where they are, but I've done close to 15,000 of these procedures and I love having the assurance that everything is done off the computer. It enables you to do a more complete procedure.'

Medtronic, which dominates the market and has a reputation for durability, has also made registration a breeze, says Dr. Nachlas. 'Once you register the patient, you just touch the instruments to a pad and it automatically registers,' he says. 'It takes maybe 2 to 3 seconds.'

As companies continue to improve the technology, the key consideration — precision — becomes more advanced. 'Every time they come out with a new generation, it seems to be that much more accurate,' says Dr. Nachlas. 'This system is accurate to within a millimeter, which is fine. You don't need any more than that.'

What were once challenging inpatient cases can now be taken care of in an outpatient or office setting, he adds. 'You avoid the hospital, you avoid the general anesthesia, and recovery time is almost negligible.'

Stryker Profess
Dr. Matheny uses Stryker's newest entry, the Profess system, and raves about the innovative way it deals with line-of-sight challenges. Instead of using an infrared camera stationed above the surgical bed, one whose line of sight can easily be interfered with, or an electromagnetic system that may be disrupted by metal instruments or other metal objects, the Profess uses an 'ingenious and simple solution — a simple cell phone camera that's embedded in the handle of the instrument we're using,' he says. 'Your hand never gets in the way. You can have the scope where you want it and the instrument can still track.'

Since the cameras are inexpensive and disposable, says Dr. Matheny, Stryker 'has been able to dramatically reduce the cost of the overall system.' Easy registration is another selling point, he says. 'I've been involved since Stryker was doing market research and I didn't know whose product I was using. Our nurses remarked how easy it was to set up and get calibrated. They kept asking me when we were going to have the system that we trialed in that market study.'

Instruments are calibrated by plugging them into a USB port, 'so the registration process is literally a fraction of the time, and works the first time almost all the time,' he says. The confidence that the calibration won't drift 'reduces the stress level and the surgeon's blood pressure in the OR,' he adds. 'You can be more thorough for your patients in a much safer way.' OSM