Cataract surgery is considered a low-risk surgery. An estimated 98 percent of these surgeries do not have any adverse effects.

Some problems can develop if a patient has a pre-existing visual disorder or other health concerns that might complicate the recovery.

Endophthalmitis is a condition that can develop in the aftermath of cataract surgery. Retinal detachment is another potential issue that can occur. The risk of either occurring is very low.

Improving technology means that cataract surgery remains a very safe remedy for cataracts.

The Safety of Cataract Surgery

Cataract surgery has high rates of both success and safety, with Harvard Medical School explaining that the treatment is “low-risk, fast, and effective.” As many as 98 percent of patients report no outstanding issues.

However, in that 2 percent, there is still some risk when it comes to cataract surgery. Even though the procedure is almost always safe, it is important for patients to be aware of what might go wrong.

Of more than 200,000 people who received cataract surgery between 1994 and 2006, the American Refractive Surgery Council writes that as many as 99.5 percent of them had no severe risks that followed their surgery. Furthermore, as cataract surgery has improved with technological advancements in surgical tools and techniques, the rate of complications following cataract surgery has significantly declined.

Most of the complications that might arise after cataract surgery can be rectified with further surgery and treatment.

Though rare, the following issues are possible with cataract surgery:

  • Swelling
  • Droopy eyelids
  • Bleeding
  • Infection
  • Inflammation
  • Dislocation of the artificial lens
  • Retinal detachment
  • Glaucoma
  • Secondary cataracts
  • Loss of vision

Patients who have other eye conditions or serious medical conditions have a higher risk of developing problems after their cataract surgery. It is vital that they inform their doctor of these potential complications.

In some cases, cataract surgery may be ineffective at improving vision. For example, glaucoma and macular degeneration cause their own damage to the eye. It might be necessary for those other conditions to be treated first before the cataracts can be successfully removed via surgery.


Some eye conditions can develop after cataract surgery. One such example is endophthalmitis, a serious infection inside the eye that typically results from bacterial infections.

The two most common bacteria associated with endophthalmitis infections are the staphylococcus (“staph”) and the streptococcal (“strep”) bacteria, which normally live on human skin. The infection tends to develop in the first week after cataract surgery. Patients experience pain and redness in their eye, a loss of vision, and a yellowish discharge emanating from their eye.

The Journal of Current Ophthalmology wrote in September 2016 that the chances of developing an endophthalmitis infection after cataract surgery is 0.1 percent. It is still very important to seek medical care immediately if it happens. Without quick treatment, patients might suffer a permanent loss of vision in the affected eye.

Treatment is usually in the form of antibiotics injected directly into the eye or surgery and antibiotics.

Retinal Detachment

Another risk of cataract surgery is retinal detachment, which happens when the retina (the light-sensitive tissue that covers the surface of the eye) develops a hole or a tear and falls away (or detaches) from the wall of the eye. If this happens, the retina loses access to the blood supply it needs to keep its cells healthy.

Without this supply, the cells die off and do not regenerate. This can lead to a permanent loss of vision because the retina processes visual information and communicates that to the brain.

In “The Incidence of Retinal Detachment After Cataract Surgery,” the Open Ophthalmology Journal writes that retinal detachment happens in 1 out of every 3,000 instances of cataract surgery and requires its own surgery to address it.

Posterior Capsule Opacification

A very common risk of cataract surgery is posterior capsule opacity, also known as posterior capsule opacification or PCO. This condition is sometimes known as a “secondary cataract,” but in reality, a cataract doesn’t grow back once it is removed.

The story behind PCO is that the doctor removes the natural lens of the eye (clouded over by the protein clumps that are responsible for the cataracts) and replaces it with an intraocular lens during cataract surgery. Most of the thin, clear membrane that covers the eye’s natural lens (known as the lens capsule) is not touched during the surgery. Instead, it is left intact, and the intraocular lens is typically set within the lens capsule.

During the process of removing the cataract, the doctor will try to keep the lens capsule untouched. Not interfering with the lens capsule is what helps patients enjoy clear vision after they have their cataracts removed.

The Ophthalmology journal writes that despite all the precautions, 20 percent of patients who get cataract surgery experience a problem in this process. The posterior portion of the lens capsule turns hazy at some point during the recovery period of the cataract surgery or even months afterwards. This is because lens epithelial cells, left over after the surgery, start to grow over the lens capsule. This is what causes posterior capsule opacity and why it is erroneously known as “secondary cataracts.”

Dislocated Intraocular Lens

Another risk that might develop as the result of cataract surgery is a malpositioned or dislocated intraocular lens. When this happens, a patient will be able to see the edge of the implanted lens or may develop double vision. Visual acuity could suffer considerably if the intraocular lens is significantly dislocated.

In October 2011, the American Journal of Ophthalmology reported that between January 1980 and May 2009, more than 14,000 cataract surgeries were conducted. A review of those surgeries found that the risk of late-stage intraocular dislocation was very low. Ten years after the surgery, the risk was 0.1 percent; by 20 years, it was 0.7 percent; and 25 years after the surgery, the risk of intraocular dislocation was 1.7 percent.

A Safe Procedure

As many as 95 percent of patients who opt for a standard intraocular lens to address their cataracts have their vision fully restored to pre-cataract conditions. Patients who choose to get a premium intraocular lens might have even better vision than they did before, with an even smaller chance of a risk developing after the surgery.

The American Refractive Surgery Council reiterates that 98 percent of cataract surgeries are performed without notable complications. While any kind of surgery carries a nominal amount of risk, patients who have pre-existing vision or health conditions should disclose these to their doctor before their surgeries, so every possible precaution can be taken.


Considering Cataract Surgery? What You Should Know. (September 2016). Harvard Medical School.

Is Cataract Surgery With Vision-Correcting IOLs Safe? American Refractive Surgery Council.

Post-Cataract Surgery Endophthalmitis: Brief Literature Review. (September 2016). Journal of Current Ophthalmology.

The Incidence of Retinal Detachment After Cataract Surgery. (September 2012). The Open Ophthalmology Journal.

A Systematic Overview of the Incidence of Posterior Capsule Opacification. (July 1998). Ophthalmology.

Risk of Late Intraocular Lens Dislocation After Cataract Surgery, 1980-2009: A Population-Based Study. (October 2011). American Journal of Ophthalmology.

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