The three main types of cataracts are nuclear sclerotic, cortical, and posterior subcapsular. All three are age-related, but they form in different parts of the lens, cause different symptoms, and progress at different speeds. More than half of people over 60 have some form of cataract, making it one of the most common eye conditions worldwide.
Your eye’s lens sits behind the iris and pupil, focusing light onto the retina. It has three basic zones: a central core (the nucleus), a surrounding layer (the cortex), and a thin outer capsule. Each type of cataract is named for the zone where clouding develops, and that location determines how your vision changes.
Nuclear Sclerotic Cataracts
Nuclear sclerotic cataracts form in the center of the lens. They develop as the nucleus gradually hardens and changes color, shifting from clear to yellow and eventually to dark brown. This is the most common type, affecting roughly 31% of people over 60 in global estimates. It also tends to be the slowest to progress, often taking years before it seriously interferes with daily life.
The yellowing has a peculiar early effect. As the nucleus hardens, it changes the way the lens bends light, temporarily improving close-up vision. Eye doctors sometimes call this “second sight” because people who previously needed reading glasses suddenly find they can read without them. The improvement is short-lived. As the cataract advances, both near and distance vision deteriorate, and colors start to look washed out or brownish. You may also notice that bright lights seem duller and that contrast between objects becomes harder to distinguish.
Because nuclear cataracts progress slowly, many people live with mild versions for years before needing surgery. The gradual color shift can be hard to notice on your own since both eyes typically change together, making the yellowed view seem normal.
Cortical Cataracts
Cortical cataracts develop in the outer layer of the lens, starting at the edges and working inward. They begin as small fluid-filled clefts in the cortex that become opaque, forming wedge-shaped or spoke-like white streaks that point toward the center of the lens. About 25% of people over 60 have some degree of cortical cataract.
The hallmark symptom is glare. Because the spoke-like opacities scatter incoming light rather than letting it pass through cleanly, bright headlights, sunlight, and overhead lighting can become uncomfortable or even blinding. This makes nighttime driving particularly difficult. You may also notice that the edges of objects look hazy or that your depth perception feels slightly off.
How quickly a cortical cataract affects your vision depends on where the spokes are. Opacities near the periphery of the lens can exist for a long time without causing noticeable problems, since light entering through the center of your pupil still passes through clear tissue. Once the spokes extend far enough toward the center, though, vision drops more rapidly.
Posterior Subcapsular Cataracts
Posterior subcapsular cataracts (PSC) form on the inner surface of the lens capsule, right at the back of the lens. This is the least common of the three types, found in roughly 7% of people over 60, but it tends to cause symptoms faster than the other two.
The location matters. Light converges as it passes through the lens, so a small cloudy patch at the back of the lens sits right in the path of focused light. Even a relatively small PSC cataract can cause noticeable difficulty with reading, glare in bright conditions, and halos around lights at night. People often notice problems with close-up tasks first, since the pupil constricts in bright light and when focusing on near objects, funneling more light through the affected area.
PSC cataracts have the strongest link to specific risk factors beyond aging. Long-term corticosteroid use, whether oral, inhaled, or in eye drop form, is a well-established cause. Diabetes also increases the risk. Because PSC cataracts can develop in younger adults and progress relatively quickly, they are more likely than the other types to require surgery sooner after diagnosis.
How the Three Types Compare
- Speed of progression: Nuclear cataracts develop over years to decades. Cortical cataracts vary depending on spoke location. PSC cataracts often progress noticeably within months to a few years.
- Primary symptom: Nuclear cataracts cause gradual blurring and color shifts. Cortical cataracts cause scattered glare. PSC cataracts cause difficulty reading and sensitivity to bright light.
- Age of onset: Nuclear and cortical cataracts rarely cause significant symptoms before the late 50s or 60s. PSC cataracts can appear earlier, especially with steroid use or diabetes.
It is also possible to have more than one type at the same time. A person might develop nuclear yellowing in the center of the lens alongside cortical spokes at the edges, and the combined effect on vision will reflect both patterns.
Other Types of Cataracts
The three types above are all age-related, but cataracts can also form for other reasons. Traumatic cataracts result from serious eye injuries and can appear soon after the event or years later. Pediatric cataracts, though rare, are present at birth or develop during childhood. These are usually genetic but can also result from infections during pregnancy or childhood eye diseases. The National Eye Institute notes that age-related cataracts are by far the most common, accounting for the vast majority of cases.
When Cataracts Need Surgery
No eye drops, medications, or exercises can reverse a cataract once it forms. Surgery is the only treatment, and it involves replacing the clouded natural lens with a clear artificial one. The procedure typically takes under 30 minutes and is done one eye at a time.
The decision to operate is based less on a specific test result and more on how much the cataract interferes with your daily life. If you can drive, read, and do your usual activities comfortably, surgery can wait regardless of what type of cataract you have. When blurred vision, glare, or difficulty reading starts limiting things that matter to you, that is generally the right time to discuss it with an eye doctor. Most people achieve good functional vision after surgery, with the World Health Organization defining a successful outcome as vision of 6/18 or better.