$1,000 LASIK Discount Washington DC
Claim Your Discount

Common & Uncommon Complications after Cataract Surgery

6 sources cited

Last Updated

For an overwhelming number of patients, cataract surgery will cause no complications. However, as uncommon as they may be, there are some complications that can arise.

Complications associated with cataract surgery include:

  • Posterior Capsule Opacity (PCO)
  • Malpositioned Intraocular Lens
  • Detached Retina
  • Light Sensitivity (Photophobia)
  • Intraocular lens dislocations
  • Eye inflammation
  • Increased pressure in the eyeball
  • Swelling of the central retina
  • Infection or bleeding within eye
  • Non-improvement of vision

Keep reading for a closer look at these possible complications.

There are a few complications that can arise, but these tend to be minor, and they can be easily addressed if they are brought to light quickly. Examples include posterior capsule opacity and a malpositioned intraocular lens.

In cases where there are rare complications, this is usually due to the presence of underlying eye health issues and will require more involved treatment.

Cataract Surgery Complications

Cataract surgery is a very simple, straightforward procedure. In fact, it is one of the most common and successful operations.

The Ophthalmology journal reported that in a review of 221,594 cataract surgeries, 99.5 percent “had zero serious complications following the procedure.” A big reason for this is that there have been so many advancements in surgical tools and techniques, that the risk of severe complications arising during or after the surgery is notably low.

As a result, complications that arise after the surgery are rare, but they do happen. Here’s a breakdown of some of these complications:

Posterior Capsule Opacity (PCO)A layer of scar tissue forms behind the lens, leading to hazy vision. Treated with YAG laser capsulotomy.
Malpositioned Intraocular LensThe lens implant is dislocated or misplaced. Surgical repositioning is required.
Detached RetinaRare, but can occur months or years post-surgery. Requires immediate medical attention.
Light Sensitivity (Photophobia)Sensitivity to sunlight and other bright lights. Can be managed with special eyewear and resting the eyes.
Intraocular lens dislocationsDisplacement of the implanted lens, requiring medical intervention to reposition or replace.
Eye inflammationRedness, swelling and discomfort in the eye. Usually managed with medications.
Increased pressure in the eyeballCan lead to glaucoma if left untreated. Treated with eye drops, medications or surgery.
Swelling of the central retinaCan cause vision loss if not treated. Medications and laser treatment can be used to reduce swelling.
Infection or bleeding within eyeSerious and rare, can lead to vision loss. Requires immediate medical attention and possibly further surgeries.
Non-improvement of visionLikely due to underlying eye disorders such as diabetic retinopathy or age-related macular degeneration.

In most cases of complications after cataract surgery, medical treatment, resting the eyes, and additional surgery, when necessary, can easily address the problems.

Posterior Capsule Opacity

One of the most common complications that can arise after cataract surgery is a posterior capsule opacity, or PCO. It is sometimes known as a secondary cataract, but this is inaccurate. It occurs when a layer of scar tissue forms behind the lens that was implanted after the surgery.

People who develop PCO will experience vision that is hazy or blurry, similar to what they experienced when they had cataracts. This is why PCO is referred to as secondary cataracts, even though cataracts cannot grow on the artificial lens that is implanted into the eye.

Posterior capsule opacity occurs in about 20 percent of people who have cataract surgery. It can develop anywhere from weeks, to even years, after the cataract surgery, and it can cause vision loss if left untreated.

PCO is treated by use of a procedure known as YAG laser capsulotomy, a quick and painless outpatient procedure where a laser makes a small opening in the clouded capsule to allow light to shine through. PCO cannot develop a second time, so the procedure needs to be done only once.

Malpositioned Intraocular Lens

intraocular lenses

Another complication of cataract surgery that can occur is a dislocated or a malpositioned intraocular lens. If this happens, patients will be able to see the edge of the lens implant in their vision. They might even have double vision. If the lens misplacement is not addressed, loss of vision is a certainty.

The intraocular lens can become displaced because the capsular bag into which it is placed is incredibly thin — only as thick as a single red blood cell — and can easily break. Ophthalmologists will try to keep the capsular bag intact and in place, to ensure that the intraocular lens is secure and properly positioned. But because the capsular bag is so fragile, the IOL can move.

If this happens, the doctor can surgically reposition it, either by sewing it back into position or using another kind of intraocular lens. If the lens is displaced soon after cataract surgery, it is important to reposition it quickly. The longer a lens implant is out of place, the more likely it will “scar” itself into place and then become more difficult to remove.

If a doctor takes quick action when their patient reports double vision or actually seeing the edge of the lens, there’s a chance the displaced lens can be fixed or replaced, with a better likelihood that the problem will not occur again.

Detached Retina

A detached retina can occur after cataract surgery, but this can happen months, or even years, later. Most patients will not suffer too much if they contact their doctor as soon as they notice the symptoms and treatment can happen as soon as possible. However, a small number of patients who do not alert their doctor when their vision suffers may experience a permanent reduction in their vision.

Like most complications that can occur after cataract surgery, instances of a detached retina are very uncommon. The Digital Journal of Ophthalmology writes that they happen in just 1.5 percent of patients.


Some patients experience sensitivity to sunlight and other bright lights after their surgery. They might benefit from eyeglasses with photochromic lenses, which automatically darken when they detect UV rays. Glasses with anti-reflective coating and progressive lenses can help with presbyopia.

In time, however, even these problems should resolve. Some level of photophobia is considered a normal side effect of cataract surgery.

If the sensitivity to light is intense and disruptive, it can be addressed with eye drops, vision aids, and a program of resting the eyes.

Uncommon & Serious Complications

Serious complications from cataract surgery are very rare. If vision loss does occur, it is likely the result of infection or bleeding within the eye.

It is possible that in a small number of patients, vision does not improve after their cataract surgery. If this is the case, it is likely that they have underlying eye disorders, such as diabetic retinopathy and age-related macular degeneration. The presence of these conditions will likely require a combination of further treatment, such as medications, surgery, and vision aids.

However, for an overwhelming number of the people receiving cataract surgery, the procedure is painless, quick, and without significant problems, side effects, or complications.


  1. Cataract Surgery Complication Rates. (August 2008). Ophthalmology.
  2. Posterior Capsule Opacification. (March 2015). Kellogg Eye Center.
  3. Intraocular Lens Dislocation. (2016). American Society of Retina Specialists.
  4. The Risks and Benefits of Cataract Surgery. (October 2002). Digital Journal of Ophthalmology.
  5. Extreme Photophobia After Cataract Surgery. (March 2014). American Academy of Ophthalmologists.
  6. Cataract and Diabetic Retinopathy. (September 2011). Community Eye Health.

The information provided on this page should not be used in place of information provided by a doctor or specialist. To learn more, read our Privacy Policy and Editorial Policy pages.