Cataract Surgery Technology
On this page
Technological advancements have made it possible for patients to undergo cataract surgery in a matter of minutes, and experience life-changing improvements in vision within 24 hours.
Cataracts are a progressive clouding of the crystalline lens, which can eventually lead to blindness. Surgery is the only permanent solution. The American Society of Corrective and Refractive Surgery reports that cataract surgery is the single most commonly performed surgery in the world, with approximately three million surgeries taking place each year in the United States alone. The sophisticated tools used in modern cataract surgery make it virtually painless and incredibly effective. In fact, most patients who undergo cataract surgery today no longer require corrective eye wear.
By using a combination of advanced laser technology, hand-held tools, ultrasound, and custom intraocular lenses (IOLs), I have personally helped many patients to regain the independence and confidence that only clear vision can provide. Patient education is essential to the success of any surgical procedure, and if you are experiencing cataract symptoms, or if you have been diagnosed with cataracts and are considering surgery, it is important to understand how this technology is used to maintain your safety and provide the best possible results.
Cataracts and the Evolution of Cataract Surgery
The crystalline lens lies behind the cornea. It helps focus light upon the retina at the back of the eye, which creates electrical impulses that are carried to the brain and perceived as visual images. The lens is responsible for approximately one third of the total focusing power of the eye. In adults, the crystalline lens is about 10 millimeters in diameter, about the same size as a pencil eraser.
The crystalline lens consists of water and protein. At any point in your life - usually after age 40 - the proteins can begin to clump together, causing vision to become clouded. While it is widely accepted that excessive ultraviolet light exposure, trauma, and other conditions can spur the development of cataracts, the precise cause of this condition remains unknown. Having cataracts is often described as being similar to looking out of a dirty window pane. The symptoms are usually gradual. Patients describe colors as appearing slightly faded in the earliest stages of cataracts. In later stages, vision may be limited to only being able to distinguish between light and dark. In fact, the lens itself becomes so clouded that it appears yellowish or milky white from the outside.
In early stages of cataracts, you can continue to see relatively clearly by maintaining an up-to-date glasses prescription and using ample light when reading. However, the condition can only be permanently corrected by surgically removing the lens and replacing it with an IOL. The modern approach to cataract surgery treats one eye at a time, usually with about a month in between surgeries.
The first documented cataract surgery took place in the 5th Century B.C.
The first documented cataract surgery took place in the 5th Century B.C., and it involved dislodging the lens from its proper position, allowing it to float freely in the vitreous cavity of the eye. Of course, this did nothing to restore focus. It wasn't until the late 1700s that doctors were able to actually remove the lens. At this time, the lens had to be removed in one piece, and the incision followed half way around the circumference of the cornea. Because fine sutures were still many years away, patients had to be completely immobilized during recovery.
One of the most significant breakthroughs in cataract surgery occurred in 1967, when Dr. Charles Kelman used ultrasound (high-frequency sound waves) to break the lens into pieces that could be removed through a smaller incision. Today, the femtosecond laser is often used to initially break the lens into quadrants. Ultrasound is still used to break the lens down further, and the standard device used to administer the ultrasound doubles as a suction tool that removes the pieces.
Until the late 20th Century, there was no solution for replacing the lens, and patients had to wear especially thick glasses that afforded only limited vision following surgery. The first IOL, developed by Dr. Harold Ridley, gained FDA approval in 1981. Ridley treated many Royal Air Force casualties during World War II. At that time, he noticed that when shards of acrylic plastic from exploded aircraft cockpits became lodged in a soldier's eye, they did not trigger rejection.
Based on this discovery, he created his first acrylic plastic IOL prototype in 1949. This marked the beginning of an arduous fight to gain acceptance in the medical community that would last more than 30 years. Ironically, the IOL is now one of the most commonly administered prostheses used in medicine today - it is virtually unheard of for a patient to undergo cataract surgery without having an IOL placed.
Ridley himself underwent IOL implantation in the 1990s, a time when advancements in IOLs were presenting exciting new possibilities that have made significant improvements in millions of patients' quality of life.
Monofocal and Premium IOLs
IOLs look fundamentally similar to the natural crystalline lens - that is, they consist of a small clear disk. However, IOLs typically have two "arms" on opposing sides of the disk that can be contracted. Once the IOL has been placed, the arms exert outward pressure, keeping the device firmly in place within the eye.
The first IOLs were monofocal, correcting only distance vision. Monofocal IOLs are still considered the standard, and are covered by most insurance plans. Most patients who receive monofocal IOLs will continue to use glasses for reading and other tasks requiring close focus.
Today, there are premium multifocal IOL options that can correct near (for reading), intermediate (computer use, watching television), and distance vision. There are also several options in accommodating IOLs, which move with the action of eye muscles to achieve focus at multiple distances. If you are a candidate for a multifocal IOL, I would personally recommend this lens to any cataract surgery patient wishing to improve focus at multiple distances, as I find they provide consistently better results.
If you have ever had perfect or near-perfect vision without glasses, it is important to note that multifocal lenses will not restore that same quality of vision. Nonetheless, they come very close, and can reduce or eliminate a patient's need for glasses at all distances.
Connie now enjoys 20/20 vision, and does not require corrective eyewear to read or drive
Connie is a 60-year-old patient of mine who is experiencing tremendous benefits after undergoing cataract surgery involving the placement of a multifocal IOL. She had suffered with severe vision problems most of her life.
"I haven't been able to see properly since I was 5 years old," Connie said. "When I was offered an option to help me see normally, I was ready to do it."
Though her vision had been a constant struggle throughout her life, the final straw was the development of cataracts.
"My cataracts came on very quickly," Connie said. "When I went to see Dr. Clark, he told me they had developed to a point where it was unsafe to keep driving. Next, his assistant told me about multifocal lenses, and I thought they were kidding me. Could something like this really be true? I had my surgery last June, and the other eye was treated in July. The prep time and actual procedure is nothing at all to go through. It took about 10 minutes in all. I went in for the post-op after my second surgery and he told me I could drive, all in a day's time."
Connie now enjoys 20/20 vision, and does not require corrective eyewear to read or drive.
"I can't believe what I can see - shapes, colors - I'm in an amazing world," she said.
While multifocal IOLs have made incredible changes in many of my patients' lives, I'm also a big fan and early adopter of toric IOLs, which are designed specifically to help patients with astigmatism. Astigmatism occurs when the cornea is oval shaped instead of spherical, resulting in blurred vision, halos, and other aberrations at all distances. The correction that toric IOLs provide is highly accurate, and is capable of restoring 20/20 vision for some patients. Many of my patients have been ecstatic over the results toric lenses provide.
The Femtosecond Laser
Before the advent of the femtosecond laser in 2001, every step in cataract surgery was performed using handheld instruments. In fact, diamond blades are still safely and effectively used for certain applications in many practices, including my own. Femtosecond (or "femto") lasers are capable of delivering one quadrillion pulses of laser light per second. In many practices, femto lasers are replacing keratome blades as the preferred method of creating the corneal flap in LASIK eye surgery.
Today, the femto laser can be used in four important steps of cataract surgery:
Corneal incisions: These small incisions placed in the cornea grant access to the lens capsule, and serve as the avenue of removal for the clouded crystalline lens. The incisions created using the femto laser are so precise that they require no sutures following surgery.
Capuslotomy: The crystalline lens is contained by a transparent membrane that completely surrounds the lens. During the capsulotomy, the femto laser is used to remove the front half of the capsule, while leaving the back half intact, where the IOL is placed.
Breaking down the Clouded Lens: Following the capsulotomy, the femto laser is used to soften the clouded lens. This prepares the lens for phacoemulsification, the process of breaking the lens into four quadrants using an ultrasound needle. The same device will subsequently vacuum the pieces from within the eye through the corneal incisions.
Limbal Relaxation Incisions (LRI): This optional step is used to correct astigmatism as part of cataract surgery. LRIs can refine the shape of the astigmatic patient's cornea by "relaxing" the oval-like curvature to achieve a more round shape. While certainly effective in some cases, I have personally found that the results of LRIs are not as predictable as those that toric lenses can provide, and I usually recommend that patients consider a premium IOL instead.
After using the femto laser in more than 200 procedures, I find that it provides the very best advantages when used to perform the capsulotomy and the breaking down of the lens
After using the femto laser in more than 200 procedures, I find that it provides the very best advantages when used to perform the capsulotomy and the breaking down of the lens. Every ophthalmologist has his or her own approach, and I actually prefer to use a handheld tool to create the corneal incisions. The femto laser does not give me the accuracy that I expect during this crucial step, though other surgeons may feel that they perform better with a femto laser.
Though cataract surgery is the most common surgical procedure performed in the world today, it is important to understand that there are several different approaches, and it always pays to be very discriminating when selecting surgeon. Advanced technology can undoubtedly increase your chances of undergoing a successful procedure with long-term benefits, but it is equally important to choose a surgeon who has a reputation for delivering excellent results. Technology, after all, is only as effective as the surgeon using it.
While the IOL and the femtosecond laser helped make invaluable strides in the safety and effectiveness of cataract surgery, other important technology used in this process has remained relatively simple, especially in the diagnostic stage. For instance, if your vision suddenly changes - a common symptom of cataracts - your optometrist or ophthalmologist will probably begin by administering a standard eye test involving an eye chart and a refractor. These tests will measure a person's visual acuity and give your doctor the precise measurements needed to aid in choosing an IOL specifically for you.
The tried-and-true tool for diagnosing cataracts and many other conditions is the slit lamp, a device that was conceptualized in 1911, and has continued to evolve over the years to become more accurate. The basic concept is that the slit lamp shines a very thin sheet (or "slit") of light into the eye, illuminating both the posterior and anterior segments of the eye. A biomicroscope is then used to magnify this view, allowing your ophthalmologist to fully analyze the cornea, crystalline lens, iris, conjunctiva, and sclera. This can require the use of special eye drops to dilate the pupils in order to maximize visibility.
When viewed using a biomicroscope and slit lamp, a lens affected by cataracts will clearly show clouding. This one-of-a-kind view allows your doctor to identify which stage your cataracts have reached, and determine an appropriate course of action.
Ensuring the Highest Levels of Safety and the Best Possible Outcomes
It is estimated that by age 80, most patients develop cataracts. Fortunately, we are living in an era when the onset of cataracts means anything but an end to your vision. While cataract surgery patients of the past were fortunate to be able to achieve marginal vision following surgery, today's patients have options that make it possible to achieve 20/20 vision.
While no one looks forward to needing cataract surgery, technology has transformed the experience into something that is virtually painless, takes mere minutes to complete, and can provide incredible benefits for the rest of our lives. If you have been diagnosed with cataracts, use this information to ask your surgeon plenty of informed questions about the technology they use during surgery, and how these innovations are used to ensure the best possible outcomes.
Want More Information?