Cataracts

A cataract is a clouding of the normally clear lens of the eye. Proteins in the lens break down and clump together, scattering light and reducing the sharpness of the image that reaches the retina. Cataracts develop gradually and are the leading cause of vision loss worldwide, though they are highly treatable.

Most cataracts are age-related. Surgery to replace the cloudy lens with a clear artificial intraocular lens is one of the most common and successful operations performed. When vision decline interferes with daily activities, cataract surgery can restore clarity and improve quality of life.

Common signs and symptoms include:

• Clouded, blurred, or dim vision
• Increasing difficulty with vision at night
• Sensitivity to light and glare; halos around lights
• Need for brighter light for reading and close work
• Fading or yellowing of colors
• Double vision in a single eye
• Frequent changes in eyeglass or contact lens prescription

Cataracts usually develop in both eyes, but not evenly. One eye may be noticeably worse than the other.

Most cataracts result from aging-related changes in the lens. Other causes and contributors include:

• Diabetes
• Long-term corticosteroid use
• Prior eye surgery or eye injury
• Radiation exposure
• Excessive ultraviolet sunlight exposure
• Smoking and heavy alcohol use
• Congenital cataracts present at birth or developing in childhood (genetic, metabolic, or infection-related)
• Certain genetic and metabolic disorders

Risk factors include:

• Increasing age
• Diabetes
• Smoking
• Obesity
• High blood pressure
• Previous eye injury or surgery
• Prolonged corticosteroid use
• Excessive sun exposure without UV protection
• Family history of cataracts
• Significant alcohol use

If untreated, cataracts cause progressive vision loss that can lead to legal blindness. Dense cataracts can make examination of the retina more difficult and, rarely, contribute to elevated eye pressure. Cataract surgery complications are uncommon but can include infection, inflammation, bleeding, retinal detachment, secondary membrane formation, and refractive surprises. Most complications are manageable when recognized promptly.

While aging cannot be avoided, you may reduce risk or slow progression by:

• Not smoking
• Managing diabetes and other chronic conditions
• Wearing sunglasses that block UVB rays
• Eating a diet rich in fruits and vegetables
• Limiting alcohol
• Having regular eye examinations, especially after age 60

An ophthalmologist or optometrist diagnoses cataracts with:

• Visual acuity testing
• Slit-lamp examination of the lens and other eye structures
• Dilated retinal examination
• Tonometry to measure eye pressure
• Additional testing (contrast sensitivity, glare testing, biometry) when surgery is planned

The decision to operate is based primarily on how much the cataract affects daily activities, not on a specific percentage of clouding.

Make an eye appointment if you notice clouding, blurring, glare, or other vision changes. Sudden vision loss, eye pain, or a dramatic increase in floaters or flashes requires urgent evaluation for other conditions such as retinal detachment or acute glaucoma.

Early cataracts may be managed with updated eyeglasses, brighter lighting, anti-glare lenses, and magnifiers. When vision loss interferes with driving, reading, work, or hobbies, surgery is the only effective treatment.

Cataract surgery typically involves:

• Phacoemulsification — ultrasound breaks up the cloudy lens, which is removed through a small incision
• Implantation of an intraocular lens (IOL) — monofocal, toric (for astigmatism), multifocal, or extended-depth-of-focus lenses according to visual goals and eye health
• Outpatient procedure under local anesthesia; recovery is usually rapid
• Second-eye surgery scheduled after the first eye stabilizes when both eyes are affected

YAG laser capsulotomy treats posterior capsule opacification (“secondary cataract”) if it develops months or years later.

After surgery:

• Use prescribed eye drops as directed
• Avoid rubbing the eye and protect it as advised
• Avoid swimming, heavy lifting, and dusty environments for the recommended period
• Attend all follow-up visits
• Report increasing pain, redness, discharge, or vision decline promptly
• Update glasses after the eye has stabilized if needed

Bring:

• Description of vision problems and how they affect daily activities
• List of medicines and eye drops
• Personal and family history of eye disease
• Questions about IOL options, recovery, and expected visual outcomes
• Current glasses or contact lens prescription