Experiencing a decline in vision after cataract surgery can be concerning. While cataract surgery is a highly successful procedure that restores clear vision for many, there are several reasons why eyesight might appear to worsen afterward. This article explores common, treatable explanations for such vision changes.
Normal Healing and Recovery
Immediately following cataract surgery, temporary visual symptoms are normal as the eye heals. These can include mild blurriness, fluctuating vision, increased sensitivity to light, a gritty or scratchy sensation, and new floaters.
These effects are part of the natural healing process. Blurriness, often caused by swelling, usually subsides within a few days to a week. Most discomfort and visual disturbances resolve within several weeks as the eye adjusts to the new intraocular lens.
Secondary Cataract
The most frequent reason for vision worsening months or even years after initial cataract surgery is Posterior Capsular Opacification (PCO), also called a “secondary cataract.” PCO occurs when a film of tissue forms on the clear membrane (posterior capsule) that holds the implanted intraocular lens (IOL) in place. This clouding occurs due to residual lens epithelial cells growing on the capsule.
Symptoms of PCO, similar to the original cataract, include hazy or blurred vision, glare, halos around lights, and difficulty with night driving. PCO is common, affecting 20-50% of patients within two to five years post-surgery. Treatment for PCO is a quick, effective in-office procedure called YAG laser capsulotomy. During this procedure, a laser creates a small opening in the clouded capsule, restoring clear vision.
Uncorrected Refractive Errors
Cataract surgery replaces the cloudy natural lens with a clear artificial intraocular lens (IOL). However, it does not always correct all pre-existing refractive errors, such as nearsightedness, farsightedness, or astigmatism. Some individuals may still require glasses for certain activities after successful surgery.
Glasses may be needed for residual astigmatism, an irregularly shaped cornea, which can cause blurred or distorted vision. Additionally, an IOL typically provides clear vision at one focal point; patients might still need reading glasses for close-up tasks or distance glasses for specific activities like night driving. These needs are expected outcomes based on the eye’s shape and IOL type, not complications. Various vision correction options remain available.
Other Ocular Conditions
Vision changes after cataract surgery can also stem from other pre-existing eye conditions, or those that develop independently. Conditions like age-related macular degeneration (AMD), glaucoma, or diabetic retinopathy can progress and affect vision regardless of cataract surgery. Cataract surgery addresses the cloudy lens but does not treat these underlying diseases.
For instance, glaucoma patients may still experience visual field progression after cataract surgery, despite improved intraocular pressure. Similarly, macular degeneration affects central vision, and its progression can worsen eyesight. These conditions impact visual acuity and overall eye health, separate from the cataract procedure’s success.
Surgical Complications
Rare surgical complications can lead to significant vision loss after cataract surgery. One complication is cystoid macular edema (CME), where fluid accumulates in the macula, causing blurred or distorted central vision, typically two to eight weeks post-surgery. CME often results from post-operative inflammation and is usually treatable with eye drops or injections.
Another serious, uncommon complication is retinal detachment, where the light-sensitive tissue at the back of the eye pulls away from its normal position. Symptoms include a sudden increase in floaters, flashes of light, or a shadow in peripheral vision, requiring immediate medical attention. Endophthalmitis, an infection inside the eye, is a rare but severe complication causing pain, redness, and rapid vision decrease, necessitating urgent treatment.