Visual condition

Cataract

Gradual clouding of the eye's natural lens, leading to yellowed, hazy vision and bothersome halos and starbursts around lights.

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What it looks like

Cataracts cause vision to look as if you're seeing through a foggy or yellowed window. Colors appear muted — blues especially fade. At night, bright lights produce noticeable halos and spike-like starbursts that can make driving uncomfortable. Some patients see ghost double-images from one eye (monocular diplopia). Reading often requires more light than before. Symptoms progress slowly over years.

Why blues fade specifically

In nuclear cataracts (the most common type), the central lens proteins denature and turn yellow then amber then brown. This yellowing preferentially absorbs short-wavelength (blue) light, so blues appear dimmer and harder to distinguish from blacks and grays.

When to see a doctor

Cataracts are extremely common after age 60 and are not dangerous, but they're also one of the most treatable eye conditions — outpatient surgery to replace the cloudy lens with a clear artificial one is highly successful. See an ophthalmologist when cataracts interfere with daily activities like driving at night.

Also known as

Nuclear sclerosis · Cloudy lens

VisualSim is a communication tool — it helps you show your doctor what you see. It is not a diagnostic tool and is not a substitute for medical advice, examination, or treatment. If you are experiencing sudden flashes of light, new floaters, sudden vision loss, severe headache, or one-sided weakness or numbness, seek medical attention immediately.

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