In the past few years, cataract surgery has undergone many changes. From the way we perform surgery and the types of IOLs we implant to the methods we use to evaluate and counsel patients, these changes are all in direct response to our patients’ wants and needs. People who come in for cataract surgery today expect better refractive results than previous generations of patients, simply because most know about the precise outcomes that friends, family members, or they themselves have had with LASIK—a true refractive procedure that provides a high level of visual function without the need for distance correction.
As baby boomers come into the cataract age, their desires are no different today at age 65 than they were 20 years ago when they had LASIK. In other words, they want to be independent of spectacles and contact lenses after cataract surgery. As a direct result of these heightened demands for cataract surgery, manufacturers and surgeons have made conscientious efforts to make cataract surgery a true refractive procedure.
IMAGE-GUIDED SURGERY WITH THE VERION
The present generation of advanced technologies in cataract surgery is helping to improve patients’ visual outcomes. Some of the most recent developments, such as the Verion Image Guided System (Alcon), perhaps the most important component of the company’s Cataract Refractive Suite, enable image-guided surgery. Other components of the suite include the LenSx Laser, Luxor LX3 with Q-Vue Ophthalmic Microscope, and Centurion Vision System.
In addition to imaging the eye, the Verion Image Guided System can be used by surgeons to plan surgery and guide the procedure. Verion’s reference unit performs necessary measurements of the eye in a single step (Figure 1A and 1B), and the planning unit performs the IOL calculation by directly importing the data from the reference unit. Information can then be passed on to the LenSx laser (Figure 1C) and the ophthalmic microscope.
Reference unit. The reference unit captures a high-resolution digital reference image of the patient’s eye, which is then used as a guide for other steps in the personalized procedure. This fingerprint of the eye depicts the limbus, surrounding scleral vessels, and iris features and is used for registration and positioning of the incisions precisely during surgery.
In the past, limbal relaxing incisions (LRIs)—although safe to do and somewhat effective—provided variable results, mainly because of variability in the depth of the incisions and because the position of the incision was guided only by identifiable landmarks on the cornea that were marked preoperatively. Now, however, surgeons can rely on the image of the eye taken with the reference unit to accurately guide the placement of these incisions at a precise depth.
Planning unit. One of the advantages of the Verion is that the reference unit transfers information seamlessly to the planning unit, avoiding transcription errors that can occur with manual input. Once this information is transferred, the planning unit can use a number of proven algorithms to predict the spherical and cylindrical IOL power needed, allowing the surgeon to look at a variety of treatment options and the corresponding potential results. For example, one can manipulate the lens calculations to determine whether arcuate incisions alone, a toric IOL alone, or a combination of the two is the best option for astigmatism correction. In the same way that we have traditionally customized spherical powers, we can now customize cylindrical refractive power.
The Verion is essentially the brains of the Cataract Refractive Suite, and it is the component that I advise surgeons to invest in first. However, pairing the Verion with other technologies such as a femtosecond laser system for cataract surgery creates a powerful tool. Therefore, the second most crucial component of the Cataract Refractive Suite is the LenSx Laser System. The information generated by Verion’s reference unit is transferred seamlessly to the laser, and use of the reference image and the surgical plan as a guide is the most accurate and precise way to place primary, secondary, and arcuate incisions.
The LenSx is also capable of performing other important steps in cataract surgery, such as the capsulorrhexis (Figure 2). The laser’s SoftFit Patient Interface improves the quality of the capsulorrhexis, reduces the incidence of tags, decreases the amount of pressure that is applied to the eye during fixation, and assures a complete capsulorrhexis when compared with earlier generations of femtosecond lasers. Additionally, the laser is now capable of creating a matrix pattern in the lens, which is essentially a cube-type pattern that cuts the nucleus into small cubes allowing tremendous versatility in the surgical technique used by the surgeon.
ANSWERING THE CRITICISM
There has been some criticism that using today’s advanced technologies might improve outcomes by only 3% to 5%. The way I see it is this: If we add up the 3% to 5% improvement with the Verion or other image-guided surgery system, 3% to 5% improvement with the LenSx or another femtosecond laser, and 3% to 5% improvement in accuracy of incision or toric IOL placement (Figure 3), suddenly there is a 9% to 15% improvement over where we were without these technologies. Every generation of new technologies allows us to come closer to reaching the same kinds of statistical improvements that we have achieved in corneal refractive surgery.
Another criticism of these advanced technologies is their cost. Does one have to purchase all of this available equipment to get the kinds of results we are after? No. I think about this the same way I thought about my stereo system when I was in college. I had a small budget that did not allow me to go out and buy the best turntable, tuner, speakers, and tape deck all at once. Instead, I bought these components one at a time, and I was able to still have a good stereo system overall that I could improve upon as I could afford it. The same can be done with advanced cataract surgery equipment; as I outlined above, the first two components to consider purchasing are the Verion and the LenSx laser.
Until we reach a point where cataract surgery is as successful in its refractive outcomes as is corneal refractive surgery, it will be nearly impossible to satisfy all patients; however, with systems such as the Cataract Refractive Suite and its components such as the Verion and LenSx we can come close.
For quite some time, we have been able to provide patients with a better level of vision than they had before they developed cataracts; now, however, we must strive to provide them with a better level of vision than they have ever had in their lives. Today, we have some of the tools and technology to do that.
Stephen S. Lane, MD, is the Medical Director of Associated Eye Care in St. Paul, Minnesota, and an Adjunct Clinical Professor at the University of Minnesota in Minneapolis. Dr. Lane states that he is a consultant to Alcon. He may be reached at tel: +1 651 275 3000; e-mail: firstname.lastname@example.org.