Cataract surgery replaces your eye’s clouded natural lens with a clear artificial one, and the entire procedure typically takes less than 30 minutes. It’s one of the most commonly performed surgeries in the world, with roughly 90% of all patients achieving 20/40 vision or better afterward. Here’s what happens before, during, and after the operation.
Preparing in the Days Before
Your surgeon will prescribe eye drops to start using before the day of surgery, typically an antibiotic to prevent infection and an anti-inflammatory to reduce swelling. Starting these drops ahead of time primes the eye for a smoother procedure and better healing. You’ll also have a preoperative exam where your surgeon measures the shape and length of your eye. These measurements determine which artificial lens will be implanted.
What Happens on Surgery Day
When you arrive, the surgical team will place dilating drops in your eye to widen the pupil, giving the surgeon access to the lens behind it. You’ll be positioned on an operating table, and the area around your eye will be cleaned and draped.
For anesthesia, numbing eye drops are used in virtually all cataract surgeries. Some surgeons also use a technique called a sub-Tenon block, where additional anesthetic is delivered around the eye after the drops take effect. You may feel brief pressure or mild stinging for a few seconds as it’s given. This deeper numbing relaxes the eyelids, blurs vision in that eye, and limits eye movement. Most patients also receive light sedation through an IV, which keeps you relaxed and less aware of your surroundings. General anesthesia, where you’re fully asleep, is reserved for special circumstances.
The Incision
The surgeon begins by making a tiny incision in the cornea, the clear dome at the front of your eye. In traditional surgery, this is done by hand with a small blade. In laser-assisted surgery, a computer-guided femtosecond laser creates the incision instead. The laser approach allows the surgeon to program the exact location, size, and depth of each cut, improving precision and consistency. Both methods produce an incision small enough that it usually seals on its own without stitches.
Through this incision, the surgeon also creates an opening in the lens capsule, the thin membrane that holds your natural lens in place. Think of it like peeling a window in the wrapper of a piece of candy so you can get the candy out while keeping the wrapper intact. That capsule stays in your eye and will hold the new artificial lens.
Breaking Up and Removing the Lens
This is the core of the operation. A technique called phacoemulsification uses ultrasound energy delivered through a tiny probe inserted into the eye. The probe vibrates at ultrasonic frequencies, breaking the clouded lens into small fragments. Ultrasound power can be delivered continuously or in short pulses and bursts. Intermittent delivery minimizes total energy exposure, which is gentler on surrounding eye tissue.
The process happens in stages. First, the surgeon sculpts the lens, carving grooves into it with low suction. Then they chop the remaining nucleus into smaller pieces using higher vacuum to grip the fragments. Throughout, a constant flow of fluid irrigates the eye, keeping it inflated and stable while suction simultaneously removes the broken-up lens material. Maintaining balanced fluid flow is critical: too much outflow too quickly could cause the front chamber of the eye to collapse.
Implanting the New Lens
Once the clouded lens is fully removed, the surgeon inserts a folded artificial lens (called an intraocular lens, or IOL) through the same small incision. The lens unfolds inside the eye and settles into the existing lens capsule. There are several types to choose from, and your surgeon will discuss options before the procedure.
- Monofocal lenses have a single focusing distance. Most people choose distance vision, which helps with activities like driving, then wear reading glasses for close-up tasks. Some people opt for “monovision,” where one eye is set for distance and the other for near vision.
- Multifocal lenses contain several focal zones, allowing your brain to select the right focus for a given task. They can reduce dependence on glasses for both distance and reading, but one tradeoff is that you may notice halos or rings around lights at night.
- Toric lenses correct astigmatism, an irregular curve in the cornea that causes blurry vision. They’re available in monofocal and multifocal versions.
What You See and Feel During Surgery
You’re awake for most cataract surgeries, but the combination of numbing drops and sedation means you won’t feel pain. Patients typically see bright lights and vague shapes but can’t make out what the surgeon is doing. With heavier sedation, many people remember very little of the procedure afterward. The surgery itself usually lasts 15 to 20 minutes.
Recovery Room and Going Home
After surgery, the team monitors you for about 15 to 30 minutes. Your eye will likely be covered with a protective shield. You won’t be able to drive, so you’ll need someone to take you home. Before you leave, the clinic will schedule your first follow-up appointment.
The First Days and Weeks
Your surgeon will prescribe antibiotic and anti-inflammatory eye drops to use for several weeks after surgery. Vision often begins improving within a day or two, though it can be blurry or slightly hazy at first as the eye heals. Many people notice colors appear brighter or more vivid almost immediately, because the yellowish cataract that was filtering light is gone.
For the first couple of weeks, you’ll need to avoid heavy lifting and bending at the waist, which can increase pressure inside the eye. Your surgeon will assess your healing at follow-up visits and let you know when these restrictions can be lifted based on your individual progress. Most people return to normal daily activities within a few days, and driving is often cleared at the first post-op appointment if your vision meets the standard.
Risks and Success Rates
Cataract surgery has one of the highest success rates of any surgical procedure. When all patients are included, regardless of other eye conditions, about 91% achieve 20/40 vision or better within 90 days. Among patients without complicating factors, that number climbs to roughly 95.5%.
Serious complications are rare. The most feared risk is endophthalmitis, a severe infection inside the eye. Among Medicare patients studied between 2016 and 2019, this occurred after only 0.08% of cataract surgeries, the lowest rate of any intraocular procedure. Other possible complications include swelling, increased eye pressure, and, in uncommon cases, retinal detachment. Months or years after surgery, some people develop a clouding of the lens capsule that was left in place. This is sometimes called a “secondary cataract” and is easily treated with a quick, painless laser procedure in the office.