A cataract occurs when the eye lens becomes clouded by a buildup of proteins that will obscure your vision if left untreated. Early cataracts are typically treated with an eyeglass prescription, while advanced cataracts require surgery to replace the clouded lens with a clear, artificial one. Over half of Americans aged 80 and up are living with cataracts, and there are more than a million cataract surgeries performed every year in the U.S. This brief, animated video details how a cataract occurs, and the steps involved in cataract surgery.*

Normal vision versus cataracts (0:09)

The connections between different eye structures and the brain are what enable us to see. The quality of vision largely depends on how our natural eye lens performs. Flexible and transparent, the lens is situated behind the iris inside a “capsular bag” held in place by fibers.

Normally, light is able to pass unimpeded through the lens and directly onto the retina, giving us a clear, bright image. As we age, however, protein deposits can cloud the lens, preventing light from getting through. This clouding, called a cataract, progresses slowly over time, and can lead to complete vision loss if left untreated.

Treating cataracts with surgery (1:32)

The only effective treatment for cataracts is implanting a clear, artificial intraocular lens (IOL) after surgically removing the clouded natural lens. Cataract surgery is among the safest and most common eye surgeries performed, and involves no pain.

The surgery typically takes 15-30 minutes and is done as an outpatient procedure. The steps are as follows:

• Local anesthesia, usually administered with eye drops, is used right before surgery.
• A primary incision of about 2 mm is made where the cornea (covering the iris and pupil) meets the sclera (white of the eye).
• The IOL is inserted through this opening.
• One or two smaller incisions are then made to help position the lens.
• Next, a gel-like substance is injected into the eye, to protect it during surgery. 
• Then, a roughly 5.5 mm round opening is made on the capsular bag containing the lens.
• The surgeon can remove the cloudy lens with a probe, while the capsular bag remains.
• Finally, the new IOL is implanted by injection, where it gently unfolds in the capsular bag.

After surgery (5:24)

The new lens remains centered in the eye, fixed in place, and can’t be seen or felt. The surgical incisions heal on their own.

The new artificial lens fulfills the role of the natural lens, enabling clear vision. Today’s lenses, like trifocal IOLs, offer good close-up, intermediate, and far-away vision. Patients have good odds of no longer needing eyeglasses.

*ZEISS Medical Technology (International). (2021, July 6). Cataract Surgery Animation [Video file]. Retrieved from https://www.youtube.com/watch?v=n_3cG9oeuNo

Responsum Health closely vets all sources to ensure that we always provide you with high-quality, reliable information. We do not, however, endorse or recommend any specific treatments, and the usage of a given source does not imply an endorsement of any treatment, medication, or procedure discussed within.