Dr. Lance S. Ferguson, ophthalmologist associated with Commonwealth Eyes, Lexington, is the first in central Kentucky to offer patients Catalys Precision Laser System surgery for the removal of cataracts.
“Enhanced safety and accuracy are the forte of this technology,” said Dr. Ferguson.
He should know. Dr. Ferguson, who is the current president of the American College of Eye Surgeons, estimates he has performed 48,000 cataract surgeries in his career.
Cataract, the clouding or discoloration of the lens of the eye, happens to everybody if we live long enough. If untreated, the lens finally becomes opaque causing blindness. The normal lens sits in a delicate enclosure called the capsule toward the front of the eyeball. Its function is to help focus images on the retina at the back of our eyes enabling us to see things clearly. Since recorded history began, people have been looking for ways to get the clouded lens out of the field of vision. Use of lasers is one of the latest of many improvements in treatment that have occurred over the centuries.
Dr. Ferguson has used Catalys laser for cataract removal for about one year. He says that the features of Catalys that assist him most as an eye surgeon are allowing him to create a precise incision and to soften the center of the cataract facilitating its removal. This results in less trauma to the eye. The surgeon replaces the cloudy natural lens with an implantable intraocular lens (IOL) made of plastic.
Commonwealth Eye’s website points out that every eye has a unique size and shape. The Catalys has the capability of creating a 3-dimensional map of each eye. This enables Dr. Ferguson to construct a customized treatment plan that matches that uniqueness. He says that with the 3D imaging and the laser’s ability to cut a fine line in close quarters, “Capsulotomy [the incision into the capsule to remove the cataract] is perfectly centered and sized, ensuring accurate positioning of the implant within the eye. Arcuate [in the shape of an arc] incisions to reduce astigmatism are far more accurate.”
Accurate positioning of the implant within the eye is particularly important if he is implanting high-tech IOLs made to correct near vision or toric IOLs to correct astigmatism. These IOLs must be precisely positioned to maximize their effectiveness. An appropriately-sized removal of the natural lens “anchors the implant and helps to prevent rotation, which negates the effect of a toric IOL,” Dr. Ferguson says, adding that “consistency in capsulorrhexis [a technique used to remove part of the lens capsule during cataract surgery] creates a consistent ELP—effective lens position—enhancing the overall accuracy of the refractive result, and providing less dependency on spectacles post-operatively.”
The Catalys laser Dr. Ferguson uses in cataract removal is a near-infrared femtosecond laser, that is, one capable of emitting pulses of light lasting a femtosecond. A femtosecond (symbol, fs) is a unit of time under the International System of Units equal to 10-15 second. For comparison, a femtosecond is to a second as one full second is to 31.7 million years. The short pulse time decreases the energy needed to achieve a given effect, an important consideration in cataract surgery. The laser can be focused precisely within the eye. The Catalys was developed by OptiMedica Corporation, a Silicon Valley, California, company that recently became a subsidiary of Abbott Laboratories.
LASER is an acronym standing for “Light Amplification by Stimulated Emission of Radiation.” Laser light differs from other light sources by its coherence, that is, its waves are in phase and are of one wave length. The laser’s spatial coherence means it can be focused closely, allowing extraordinary precision of cuts made with it. (It’s also the reason laser pointers work.) The temporal (time-based or sequential) coherence of lasers allows lasers to emit only one color of light and to emit pulses of light of incredible brevity.
Invented about 1960, lasers have made their way into many applications. In 1980, a researcher at IBM Research laboratory discovered that the excimer, a form of ultraviolet laser, could be used safely and with precision on living tissue. In 1989 a Greek doctor invented LASIK, another acronym standing for “Laser-Assisted In-Situ Keratomileusis (the surgical reshaping of the cornea performed in order to correct refractive errors such as myopia or astigmatism). By the mid-1990s lasik had supplanted earlier surgical methods of correcting refractive errors. Dr. Ferguson says that his previous experience with femtosecond laser lasik has aided him in making the transition from older methods of cataract removal. He also acknowledges that “close collaboration with other surgeons is invaluable.”
Although these very fast lasers have added extraordinary precision to cataract surgery, concern about using lasers so close to retinas lingers. Dr. Ferguson points out that, “Laser injuries occur because someone is shining a laser at an eye, the individual looks at it, and his or her own cornea and lens focus it directly upon…the retina….Therapeutic lasers are focused on the target tissues (in this case the…lens/cataract) which absorbs the light….The FDA and numerous investigators studying 1000s of eyes have shown no ill effect of the femtosecond laser on the retina.”
Commonwealth eyes is located at 2353 Alexandria Drive, Lexington, KY. For more information on Dr. Ferguson and his work with Catalys laser-assisted cataract surgery, call 888-751-0569 or visit their website at http://commonwealtheyes.com
By Martha Evans Sparks, Staff Writer