Cataracts: Who gets them? What causes them? Does surgery help? Some common questions about cataracts to help you understand them and how a good pair of polarized sunglasses helps prevent them.
Cataracts: What They Are, What Causes Them, and When Surgery Helps
By Gary Nesty, O.D. (Licensed optometrist in Indiana; Founder of Solar Bat)
Key takeaways
- Cataracts can affect any age group, but are most common after age 60; babies can be born with cataracts (congenital).
- Risk factors can include diabetes, injuries, infections, long-term steroid use, smoking, excessive alcohol use, obesity, and unprotected UV exposure.
- UV protection matters—look for sunglasses labeled to block all UV rays.
What is a cataract?
A cataract is a clouding of the normally clear crystalline lens inside the eye. The lens sits behind the iris (the colored part of the eye) and is centered behind the pupil. As the lens becomes cloudy, vision can be diminished—similar to looking through a cloudy windowpane instead of a clear one. The clouding results from breakdown of proteins and fibers within the lens, and cataracts often do not develop at the same rate in both eyes.
What causes cataracts (and who gets them)?
Cataracts can affect any age group but most commonly affect those over 60. Babies can be born with cataracts (congenital cataracts). Cataracts can also be related to general health conditions such as diabetes, eye injuries, recurring eye infections, and long-term use of systemic medications such as steroids—but most often, cataracts are age-related.
Certain lifestyle factors can contribute to earlier cataract development, including:
- Smoking
- Excessive alcohol consumption
- Excessive unprotected exposure to UV light (sunlight)
- Obesity
Types of cataracts (and why location matters)
The crystalline lens develops in layers before birth, much like a tree develops rings as it grows: the innermost layer is the nucleus, then the cortex, and the outermost is the posterior subcapsular layer. A cataract can develop in any or all of these layers.
The effects on vision and the growth rate are often related to the layer involved. The cortex typically affects vision the least and is usually slowest-growing, while a posterior subcapsular cataract can be fastest-growing and affect vision most significantly because it is closer to the retina.
You may have known an older family member or friend who wore glasses full time and suddenly reported they didn’t rely on them as much. Often, that person was farsighted, and a posterior subcapsular cataract can cause a nearsighted shift in prescription—reducing farsightedness.
How can you reduce the risk of cataracts?
You can reduce risks you have control over, such as smoking, excessive alcohol consumption, and obesity. When in sunlight, wear sunglasses that block all UV rays—those UV-blocking ratings are usually noted on the labeling. If you have health issues such as diabetes, do your best to keep them controlled. If you require long-term medications such as steroids, the priority is maintaining your overall health.
When are cataracts “ready” to be removed—do they have to be “ripe”?
Many years ago, cataracts had to be “ripe.” In the “old days,” the entire crystalline lens was removed, patients often stayed in the hospital for 5–7 days, and if the cataract wasn’t mature the lens could rupture during removal. After removal, patients wore very thick glasses to replace the focusing power of the lens. Later, anterior segment lens implants replaced thick glasses with a small lens implanted in front of the iris in the anterior chamber. Thankfully, those days are over.
Today, the outside of the lens is opened, the lens contents (including the cataract) are emulsified and removed, and an implant is inserted in the sac formed by the remaining outer surface of the lens. This is done through a very small incision in the clear cornea using a folded lens implant that unfolds inside the eye and is put in place. The corneal incision is self-sealing, and the cornea is the fastest healing tissue in the body. The procedure is performed microscopically and can be performed regardless of the cataract’s stage of development.
Cataract surgery is a health procedure and is covered by health insurance or Medicare. Timing is dictated by a patient’s insurance guidelines rather than the stage of cataract development. Recovery time is usually 2–3 weeks, with a typical early complaint of “feels like a hair in my eye” lasting 1–2 days. Cataract surgery is one of the safest surgical procedures a patient can undergo, and many patients do not need glasses except for reading after surgery.
How often should you have an eye exam?
- Ages 3–18: annual eye exam
- Ages 19–50: every two years
- Over 50: annual eye exam
A competent optometric exam does not just check for an eyeglass prescription—it includes a thorough evaluation of overall eye health.
Questions or topic requests
Please email any questions (or topics you’d like covered in future issues) to: garynesty@solarbat.com
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