For most people, breaking, losing, or misplacing their glasses is an annoying inconvenience. But for Christiaan Rollich, who was severely nearsighted, not wearing glasses or contacts meant not seeing at all.
"My vision was so bad the army wouldn't accept me," says Rollich, who grew up in the Netherlands and moved to the U.S. 15 years ago. "If I took out my contacts, I wouldn't be able identify anybody in the room, no matter how close they were."
Zinc is an essential trace mineral that's important for the immune system and the brain, as well as other parts of the body. In infants, zinc deficiency can delay normal development. At any age, serious zinc deficiency can lead to risk of infections.
Eye-related benefits. Zinc is believed to be important for vision because high levels of the mineral are found in the macula, part of the retina. Zinc enables vitamin A to create a pigment called melanin, which protects the eye. Some studies show...
Fortunately for Rollich, implanted contact lenses can now help people who have moderate to severe nearsightedness, or myopia. Called phakic intraocular lenses (IOL), these lenses are surgically implanted in the eye in front of the natural lens. They work by bending light rays onto the retina to form a clear image. Studies have found that IOL surgery is as safe as LASIK, which cuts the cornea to change its focusing power.
"It's the best money I ever spent," says Rollich. "Now I have pilot vision -- 20/15. I can do anything I want now. I surf, I do Thai boxing. It's really amazing."
2 Types of Implantable Lenses
There are two types of phakic implantable lenses available in the U.S. Studies show that both types are safe and work equally well to correct vision, but they do have different risks.
Note: Vision error is measured in diopters. The greater the number, the more correction needed.
The Verisyse Phakic Intraocular Lens (IOL) is made of plastic, and is attached in front of the iris. It's designed for people aged 21 years or older who have stable vision with a change in refraction of less than 0.5 diopters in six months. You are a candidate for this lens if your nearsightedness ranges from -5 diopters to -20 diopters.
The Visian Implantable Collamer Lens (ICL) is made of collamer, a substance that occurs naturally in the body, and is implanted behind the iris in front of the natural lens of the eye. It's designed for people aged 21 to 45 years who have stable vision with a change in refraction of less than 0.5 diopters in one year. You are a candidate for this lens if you have either:
A myopia correction from -3 diopters to -16 diopters.
A myopia reduction from -16 diopters to -20 diopters.
Neither lens treats astigmatism, an eye problem that often accompanies nearsightedness. So you must have astigmatism of 2.5 diopters or less to be a candidate for these two lenses.
There are other phakic implantable lenses used in Europe that can treat both myopia and astigmatism, but they have not yet been approved by the FDA for use in the U.S.
Implantable Lens Pros and Cons
"The Verisyse lens is not foldable, so it has to go in through a large incision. And that's a negative," says D. Rex Hamilton, MD, FACS, director of the UCLA Laser Refractive Center. "It also clips on the iris, and sits in front of the iris, so it's closer to the inner surface of the cornea." This means that there is a slightly higher risk of damage to the cornea, which can lead to the need for a corneal transplant.