LASER FOCUSED Vitreolysis is a non-invasive procedure that can eliminate the visual disturbance caused by floaters.

"Ican read again." "I can drive again." These are the types of symptomatic improvements we see in patients undergoing procedures like cataract and refractive surgery, but lately we're seeing these same improvements in patients undergoing laser floater removal (vitreolysis). Patients like ophthalmologist Jack Bussa, MD. He noticed that floaters — tiny clumps of cells inside the vitreous — impaired his vision after he had multifocal lenses implanted. The high-volume surgeon from Janesville, Wis., was frustrated with his vision when he showed up in my clinic to give YAG laser vitreolysis a try. After 2 sessions, the floaters had mostly disappeared and he noticed significantly improved visualization when performing cataract surgery under the microscope.

A significant number of cataract surgery patients experience post-op floaters, and many of them, like Dr. Bussa, suffer life-altering vision impairment. A lot of those patients were willing to undergo the risks of vitrectomy or silently suffered with the chronic condition. But that's changing, now that surgeons have access to improved YAG laser technology that can vaporize floaters in a matter of minutes. Here are the key clinical factors you and your surgeons need to consider when adding a new laser platform.

• Improved illumination. Vitreolysis isn't a new concept, but the illumination systems on previous generations of YAG lasers were not optimized to visualize and treat floaters in the middle or posterior vitreous. That limitation increased the difficulty of identifying most floaters that are symptomatic and provided limited spatial context of where floaters sit in relation to the retina and posterior capsule — the perspective surgeons need to provide safe, effective treatment. YAG laser technology has improved dramatically in recent years. In particular, the ability to view floaters using 2 different illumination positions: coaxial illumination, or "on axis," as well as "off axis," with the slit lamp in the oblique position. In the coaxial position, the laser platform aligns with the surgeon's vision, the target illumination and the treatment beam along the same optical path and the same optical plane. This lets the surgeon focus on-axis with more depth and spatial reference when treating posterior floaters.

Vitreolysis performed with the latest illumination technology gives surgeons the confidence to use the level of energy needed to effectively vaporize floaters.

• Optimized energy. Vitreolysis performed with the latest illumination technology gives surgeons the confidence to use the level of energy needed to effectively vaporize floaters. Physicians who have reported marginal results with vitreolysis in the past often set the YAG laser's energy level to 1.2 millijoules, which is much less than the 4 to 9 millijoules that are typically required to eliminate floaters. Some physicians balk at sending that amount of laser energy into a patient's eye, but it's safer to do if you're working with coaxial illumination and consider the basic physics of laser technology. When the laser is fired into the vitreous, a small acoustic wave of energy is emitted and some of the energy wave is sent back toward the laser's source. There is a nonlinear rise in the dispersion of energy that takes place. That means increasing the laser's energy from 5 to 10 millijoules does not double the amount of energy delivered into the eye. Instead, the energy is increased by just 30 to 40%. That's an important safety concept to understand.
• Number of shots. Many surgeons stop at 50 to 60 laser shots when treating floaters, but that's not nearly enough in some cases. Our practice conducted a study involving more than 300 patients that found that about 180 shots were needed to pulverize Weiss rings/solitary opacities and 500-plus shots were needed to eliminate amorphous cloud-like floaters. It's acceptable to use that many shots because YAG laser energy is delivered in a series of 4 nanosecond pulses. The heat and energy that's generated in that time is so short-lived that they dissipate between each shot.

It took me 20 to 30 treatments before I felt fully comfortable with the procedure's parameters. It's best for novice surgeons to start with pseudophakic patients who present with Weiss rings in the middle of the vitreous. Once physicians achieve positive results with those patients, get used to employing the laser's energy levels and understand the spatial context between floaters and the eye's anatomy, they can graduate to treating phakic patients and patients with cloud and string-like floaters.

Growth potential
If your surgeons perform a couple vitreolysis procedures each week, you'll easily recoup the roughly $45,000 for an upgraded YAG laser. The best part: Patients who want this procedure are already in your surgeons' clinics and just need to be educated about the treatment that can have a profound impact on their quality of life. OSM