According to the American Academy of Ophthalmology, cataracts affect more than 24.4 million Americans aged 40 and older. By age 75, approximately half of all Americans have them. No wonder there was great interest in the Eye & Ear Foundation’s September 18th webinar, “Advancements in Cataract Surgery.”
The first part of the webinar was presented by Jerome Finkelstein, MD, FACS, Clinical Associate Professor, Vice-Chair for Clinical Operations, Chief of Ophthalmology at UPMC Oakland and UPMC Mercy, and Physician Lead for the Department’s Ophthalmic Technician Training Program.
What is a Cataract?
A cataract is a clouding of the eye’s natural lens, which grows thicker over time and eventually becomes cloudy. This condition often develops slowly as a normal age-related process. Most people over the age of 55 have some signs of cataracts.
What Causes Cataracts?
- Aging is the most common cause
- Previous eye surgery or trauma
- Spending a lot of time in the sun (especially without UV protection)
- Certain medications (corticosteroids)
What are the Symptoms of Cataracts?
- Blurry vision – like a little film of Vaseline or grease of your glasses, nothing is clear
- Faded colors
- Halos around light
- Trouble seeing at night
How Can I Slow Down the Progression of Cataracts?
A simple way to slow down the progression of cataracts is to wear sunglasses with UV protection. Nowadays, almost everything on the rack has 100% UVA and B protection, Dr. Finkelstein said. This is usually started somewhere inside the frame. Wear them when outdoors in the sun, especially in April-October in a climate like Pittsburgh. This is less concerning in the winter because of the sun’s angle.
If you smoke, stop smoking. Even if you have smoked for many years, there is still value to stopping now to slow down the progression of cataracts. If you are diabetic, keep blood glucose levels under control.
There are no eye drops that will dissolve cataracts.
How are Cataracts Diagnosed?
A comprehensive eye exam is conducted to rule out other conditions that can cause blurry vision. Seeing an optometrist to make sure your glasses and/or contact lens prescriptions are up to date is also part of the process.
When Should I Consider Cataract Surgery?
If your cataract symptoms are not bothering you much, it is not necessary to have cataract surgery. Talk to your ophthalmologist about how far along your cataract is and get their feedback. When it becomes difficult to do the normal activities you do day-to-day because of your vision, or if you feel unsafe driving, then surgery should be considered.
What is the History of Cataract Surgery?
Dr. Finkelstein painted a scenario that occurred not such a long time ago:
Patient: “Doctor, I can’t see well.”
Doctor: “You have a cataract. Come with me.”
Patient: “Will this hurt?”
Doctor: “Of course not. Please have a seat.”
As Dr. Finkelstein said, the doctor was probably not a specialist and offered false reassurance, because back then patients were basically held down by more than one person, without anesthesia, and underwent a technique known as couching. This involved inserting a sharp instrument into the eye and pushing the lens posteriorly. The lens remained in the eye out of the visual axis. Bleeding, infection, and poor vision were common. This was documented as early as 800 BC.
In 1972, a French ophthalmologist named Jacques Daviel presented before the French Royal Academy of Surgeons a paper entitled, “A New Method of Curing Cataract by Removing the Lens.” He was credited with the first modern cataract surgery. This is the way cataracts were done in Europe for a couple hundred years. Patients were still left without any lens in the eye, so focusing was very blurry. There was not much in the way of glasses back then, so it was better than not having a cataract removed if it was bad, but not by much.
World War II Intraocular Lenses & Airplanes
Dr. Harold Ridley of Moorfields, England, observed injured Hurricane and Spitfire pilots in World War II with Perspex fragments from the plane canopy. Prior to WWII, fighter planes in WWI had glass canopies. Perspex developed one of the first plastics used in a new generation of fighter planes in WWII. These planes were lighter and faster, and used extensively during the war, but they resulted in a lot of injuries – some from the shards of plastic embedding in the pilot’s body, including his eyes.
Dr. Ridley noticed these pieces did not react. They sat in the eyes and did not cause inflammation or clouding of tissues around it. He thought it would be a great idea to use this material as an implant to take the place of natural lens during cataract surgery. In the 50s and 60s, Dr. Ridley and his colleagues first in Britain and other parts of Europe and then in the U.S. developed various types of implants. Some were meant to go behind the iris, some in the front, and some were clipped to the iris. His first design was extremely heavy, as he thought he would just replace the natural lens with Perspex material. It was 20 times as heavy as the natural lens, so it could not support it. It took many years and iterations to figure out they needed something very thin and lightweight.
Phacoemulsification and the Modern Age of Cataract Surgery
A NYC ophthalmologist named Dr. Charles Kelman was sitting in the dentist’s chair when he realized that ultrasound could be used on cataracts. He invented the first machine utilizing ultrasound to remove cataracts; thus, phacoemulsification was born. Phaco = lens + emulsification = soften.
The idea was that this tool would soften or break down components of the cataract of your natural lens, and then it could be removed from the inside out. The design of the machine is such that the tip goes inside the eye to remove it. It has suction and fluid, so as it is breaking into little pieces, it is immediately suctioned out of the eye without a need for a larger incision.
It took a decade and a half before it really started to take off. Computers and software technology helped it become what it is today. This new process allowed for smaller incisions, and a faster surgery and recovery. Incision size was now limited to the diameter of the implant. Newer, flexible materials for implants were developed, allowing for even smaller incision sizes, now approximately 1/10th of an inch.
The second part of the presentation was by Roheena Kamyar, MD, Clinical Assistant Professor, Cornea, Cataract and External Disease Services, Refractive Surgery Center. She serves on the Advisory Board at the Center for Organ Recovery and Education and is Assistant Medical Director at the Eye Bank.
She described cataract surgery as being outpatient, with light IV sedation. A 2 mm incision is made. An opening is created in the lens capsule containing the cataract. The cataract is removed by an ultrasound probe, and a lens implant put in its place.
The gold standard is manual cataract surgery. It is faster, more comfortable for the patient, has no additional cost, and has less inflammation. But certain types of cataracts are more challenging to remove this way.
Femtosecond laser assisted cataract surgery is surgery in which a laser makes the incision, creates the opening in the lens capsule, and softens the cataract. This kind of surgery is helpful with certain types of cataracts, like very dense, traumatic ones, or cloudy corneas. However, it is slower, can result in more inflammation and corneal swelling, and has an out-of-pocket expense.
Multiple trials comparing manual vs laser cataract surgery have found no significant differences in outcomes. Both methods are as good in terms of vision, patient reported health, and safety outcomes. A person’s outcome depends in large part on the skill and experience of the surgeon.
Intraocular Lens Implants (IOLs)
Monofocal lens are the most common type of implants used during cataract surgery. This implant offers excellent optics and has a singular focus that can be set for distance, intermediate range, or near vision. Most people choose to have good distance vision and wear reading glasses for reading or close work.
Monovision is an option with these implants, who want one eye for distance and one eye for intermediate or near vision. Some people can have trouble with their depth perception. Sometimes it is recommended to do a trial in contact lenses. You will still need glasses in certain cases.
Multifocal implants are designed to provide both distance and near vision. Different zones are set at different powers. They provide extended depth of focus. Instead of multiple focal points, there is a single elongated focal point to enhance “range of vision” or “depth of focus.”
Multifocal and EDOF IOLs
A positive thing about these kinds of lens is that there is less dependence on glasses after surgery. Twenty percent will still need glasses for distance, while 30 percent will still need glasses for near vision. However, due to halos and glare during nighttime driving, if nighttime driving is important, patients will be steered away from this kind of lens. Decreased contrast sensitivity is one downside, along with dry eyes, which can degrade the quality of vision. Vision can also be affected if any other eye conditions develop, like glaucoma or retinal detachment.
Toric lenses are used to correct for astigmatism, a common condition where instead of the cornea being shaped round or spherical, it is elongated more like a football. To correct astigmatism with these lenses, there are monofocal or multifocal/EDOF options.
How is the Implant Power Determined?
This is not an exact science, Dr. Kamyar said. Measurements are taken to determine the length of the eye and shape of the cornea. Advanced mathematical formulas are used to estimate the power of the implant to be used for each eye. These formulas are extremely accurate but not 100 percent perfect. There is a possibility of over or under correction, especially in eyes that are very near sighted or very far sighted, or eyes that have undergone previous refractive surgery (LASIK).
Important Final Points About Lens Implants
The final outcome after cataract surgery depends on how you heal, and how the implant settles in your eye. No surgeon can guarantee what the final outcome will be. The choice of implant is not the same for everybody. “We can never guarantee that you will be glasses free after surgery,” Dr. Kamyar cautioned.
What is Drop-Less Cataract Surgery?
Instead of using antibiotic and steroid eye drops after surgery, the antibiotic and steroid are injected into the eye at the end of surgery. The pro to this method is that there is no need to use eye drops after surgery. But there is no FDA approved antibiotic agent available. Medications are usually made by a compounding pharmacy, and there is potential toxicity.
What is the Difference Between LASIK and Cataract Surgery?
LASIK is performed on a different part of the cornea, which is the window to the eye, the very front layer of your eye. The cornea is reshaped so that light can shine better on the retina and be more in focus. If there is a cataract where the lens is cloudy, no matter how you reshape the cornea, the vision will still be cloudy. So once a cataract starts developing, the only option is cataract surgery.
What are the Risks of Cataract Surgery?
- Increased eye pressure (glaucoma)
- Need for a second surgery
- Swelling in the retina or cornea
- Retinal detachment
- Vision loss
Will My Cataract Come Back?
The short answer is no. Patients can get posterior capsular opacification, a secondary cataract or secondary membrane. This can cause vision to become blurry months or years after cataract surgery. It is common and easy to treat. A laser procedure in the clinic called YAG capsulotomy is performed and only takes five to 10 minutes. There is no downtime afterwards. Vision may be blurry for a few hours after, but then it is nice and clear as it was right after surgery. This is a one-time procedure that does not need to be repeated.
Cataracts are a normal, age-related condition. Cataract surgery is performed when your symptoms are affecting the quality of vision and is not correctable with glasses or contact lenses. There are many diff IOL implant options. The choice of lens implant may be different for everyone. There have been many advances in technology for cataract surgery and there will continue to be. Talk to your doctor about whether any of these technologies will give you a better and safer outcome.