Cataracts occur when the eye's natural lens, a small oval structure behind the pupil, loses transparency and becomes cloudy. This common age-related condition affects vision by scattering light.
By age 65, about 1 in 5 people develop cataracts; this rises to 1 in 3 by 75 and nearly 2 in 3 by 85. Research links prolonged sun exposure to higher risk, with men and women equally affected. In advanced stages, cataracts can lead to blindness, but modern surgery offers excellent outcomes and restores clear vision.
Most cataracts (95%) stem from aging, known as senile cataracts. The lens hardens and clouds over time, impairing its key role in focusing light on the retina for sharp vision. Typically, one eye is more affected.
Secondary cataracts arise from underlying health issues, such as poorly managed diabetes, long-term cortisone use, radiation exposure, or eye conditions like high myopia, glaucoma, or retinal detachment.
Traumatic cataracts result from eye injuries, including blows, cuts, or burns that damage the lens.
Congenital cataracts in children are rare and may link to conditions like Down syndrome or maternal infections (rubella, toxoplasmosis, genital herpes, syphilis) passed to the fetus.
The hallmark symptom is blurred vision, like peering through a misty waterfall—hence the term "cataract," from Latin cataracta meaning "waterfall." Vision fades gradually with fog-like haze, increased glare sensitivity, and faded colors.
Progression disrupts daily tasks, eventually reducing sight to mere light perception. A visible sign is a gray or milky-white pupil instead of black.
Ophthalmologists diagnose cataracts via visual acuity tests and biomicroscopy, which magnifies the lens to gauge opacity.
Surgery is the only effective treatment, replacing the cloudy lens with an artificial intraocular lens (IOL) through a tiny corneal incision. Phacoemulsification, the gold standard, uses ultrasound to emulsify and remove lens fragments, minimizing risks. Performed under local anesthesia, it lasts 10-30 minutes, with same-day discharge and rapid vision recovery.
As the most common surgery for older adults, it often restores full distance vision and independence. Near vision may require glasses, but advanced IOLs are emerging to eliminate them entirely.
