Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nearsighted children may benefit from rigid contact lenses

14.12.2004


New research suggests that rigid gas permeable contact lenses may help slow the progression of nearsightedness, or myopia, in young children.



At the end of a three-year study of more than a hundred 8- to 11-year olds, researchers determined that wearing rigid gas permeable (RGP) contact lenses slowed the progression of myopia by nearly 30 percent, compared to soft contact lens wear.

Only recently did researchers find that young children could handle the responsibility of wearing contact lenses. Rigid contact lenses alter the shape of the cornea, which plays a small role in the development of myopia, said Jeffrey Walline, the study’s lead author and an adjunct assistant professor of optometry at Ohio State University.


He and his colleagues caution that the RGP lenses won’t stop myopia in its tracks, and also that the effects of these lenses probably aren’t permanent. But the researchers also say that RGP lenses could be a good option for nearsighted children who can adapt to wearing them. "Severe myopia, which is fairly rare, can lead to a detached retina and permanent vision loss or glaucoma," Walline said. "Theoretically, wearing RGP lenses could lessen the severity of myopia, and likewise the chances of developing one of these problems.

"But it’s also a matter of convenience – keeping myopia’s progression in check may mean that a child can see his bedside clock, or walk to the bathroom in the middle of the night without having to depend on glasses."

The study appears in the December 2004 issue of the journal Archives of Opthalmology.

While myopia can develop at any age, it most often begins during childhood, around ages 8 to 14. Progression typically slows by the mid-teens for females and by the mid-20s for males.

The researchers evaluated 116 children who participated in the Contact Lens and Myopia Progression (CLAMP) study at Ohio State. All children were given about two months to adapt to wearing the rigid contact lenses before the study officially began. "It takes most children about two weeks to get used to this type of contact lens," Walline said. "We wanted to make sure the children could handle the rigid lenses for the long-term."

At the end of the two-month initiation period, children were randomly assigned to wearing RGP lenses or two-week disposable soft contact lenses. Children returned to the optometry clinic each year for three years for annual vision checkups.

A normal eyeball is round, while a nearsighted eye is shaped like an egg – somewhat oval. This irregular shape is the most common cause of nearsightedness. "To have a permanent effect, contact lenses would ideally control the shape of the eyeball as it grows," Walline said. "The RGP lenses did not do that. However, they did change the shape of the cornea on a short-term basis."

While the cornea plays a small role in myopia’s development, the RGP lenses were able to change the cornea’s shape enough to lessen myopia’s progression by 28.8 percent. The rigid contact lenses kept a condition called "corneal steepening" to a minimum – because the nearsighted eye takes on a more oval shape, the cornea becomes steeper than that of a normal, round eye.

Soft contact lenses had no effect on the shape of the cornea, or on the progression of myopia.

The children in both groups wore their lenses an average of 70 hours a week. The researchers aren’t sure how many hours a day a child would have to wear RGP lenses in order to slow the progression of nearsightedness.

"Rigid contact lenses may offer visual and eye health benefits that soft contact lenses don’t," Walline said. "These harder lenses allow more oxygen to reach the cornea than do most soft contacts, and they do a better job controlling astigmatism. These factors, in addition to the modest myopia control, should be weighed against the initial discomfort that sometimes goes along with RGP lens wear when deciding what a child should use to correct his vision problems."

Previous studies suggest that about four out of five children can adapt to wearing RGP lenses, which cost about $160 a year, Walline said. For comparison, disposable contact lenses – like the kind used in this study – cost about $260 a year.

Walline conducted the CLAMP study with Ohio State optometry colleagues Lisa Jones, Donald Mutti and Karla Zadnik, the Glenn A. Fry professor of optometry.

CLAMP received funding from the National Eye Institute; Menicon Co, Ltd, CIBA Vision Corporation, and SOLA Optical – all contact lens manufacturers; and an American Optometric Foundation William C. Ezell Fellowship. The authors have no relevant financial interest in the sponsors of the study.

Jeffrey Walline | EurekAlert!
Further information:
http://www.osu.edu

More articles from Health and Medicine:

nachricht Rabies viruses reveal wiring in transparent brains
19.01.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht On track to heal leukaemia
18.01.2017 | Universitätsspital Bern

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland

19.01.2017 | Earth Sciences

Not of Divided Mind

19.01.2017 | Life Sciences

Molecule flash mob

19.01.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>