Featured Research

from universities, journals, and other organizations

New Contact-Lens Materials Will Revolutionize The Industry, UT Southwestern Researchers Report

Date:
January 7, 2002
Source:
University Of Texas Southwestern Medical Center At Dallas
Summary:
Researchers at UT Southwestern Medical Center at Dallas report that contact lenses, both rigid and soft, made from new hyper-oxygen transmissible materials are expected to reduce the possibility of bacterial infection better than contact lenses currently on the market. Based in part on these findings, the Food and Drug Administration recently approved hyper-oxygen transmissible contact lenses for 30-day continuous wear.

DALLAS – Researchers at UT Southwestern Medical Center at Dallas report that contact lenses, both rigid and soft, made from new hyper-oxygen transmissible materials are expected to reduce the possibility of bacterial infection better than contact lenses currently on the market. Based in part on these findings, the Food and Drug Administration recently approved hyper-oxygen transmissible contact lenses for 30-day continuous wear.

The results of the UT Southwestern study are published in the January issue of Ophthalmology, the clinical journal of the American Academy of Ophthalmology.

Dr. H. Dwight Cavanagh, senior author of the study and vice chairman of ophthalmology and associate dean for clinical services at UT Southwestern, said study results provide a firm biological foundation for increased prospective safety of the new silicone hydrogel lens materials.

“The significance of our study is that for the first time we have a scientific-based rationale that has passed peer review at high levels that exactly predicts our current epidemiological risk pattern and strongly suggests that these new lenses will be the breakthrough in reducing risk for infection that everyone has been waiting for,” said Cavanagh.

Cavanagh said conventional contact lenses disturb the surface of the cornea, thereby allowing pathogenic bacteria, such as Pseudomonas aeruginosa, to bind to the corneal surface cells and potentially initiate infection. The most significant and devastating clinical complications among contact-lens wearers have been corneal ulceration and infection, which can lead to permanent visual loss, Cavanagh said.

“Until now, no apparent clinical progress had been made in ameliorating this critical clinical problem since disposable contacts were first introduced nearly 10 years ago,” Cavanagh said.

UT Southwestern researchers examined risk estimates for contact lens-associated increases in bacterial binding by lens type and wearing schedules, which previous benchmark studies had never addressed. Cavanagh and his team followed 178 patients for a year. They compared the new Bausch & Lomb soft lenses and the Menicon rigid lenses, both made from hyper-oxygen transmissible material, in daily wear and extended wear to lenses made from conventional materials.

“This is the first randomized, prospective, masked clinical study with contact lenses that demonstrates significant difference in bacterial binding to the cornea as a function of the oxygen transmission of the lenses themselves,” Cavanagh said. “This means that there are really small amounts of increased bacterial binding seen with extended-wear, even up to 30 nights, with the novel contact-lens materials that transmit high amounts of oxygen to the eye as compared to presently available conventional materials.”

Cavanagh said the study established three important findings. First, hyper-oxygen transmissible soft-lenses produced significantly less bacterial binding than conventional lens with no significant difference between six-night and 30-night wear. Second, researchers noted for the first time a remarkable adaptive recovery after six months with all soft lenses, with a decrease in bacterial binding to the corneal surface. Lastly, 30-night wear produced no significant increases in bacteria binding after one year.

An unexpected finding of the study was that rigid contact lenses appear better for the eye than soft because they promote tear exchange, which washes out debris and allows more oxygen to reach the eye.

For the past 20 years, ophthalmologists have warned the public against wearing contact lenses overnight because it could make them more susceptible to eye infections.

According to the Contact Lens Institute, more than 30 million Americans and 75 million individuals worldwide currently use contact lenses as an alternative to eyeglasses to correct refractive eye problems.

Other UT Southwestern ophthalmology researchers involved in the study were Dr. Patrick Ladage, postdoctoral researcher; Mike Molai, research study coordinator; Dr. Ling Li, research associate; Dr. W. Matthew Petroll, associate professor; and Dr. James Jester, professor.

The research was supported in part by the National Institutes of Health, Bausch & Lomb, Menicon, Research to Prevent Blindness, the Pearle Vision Foundation and the Chilton Foundation.


Story Source:

The above story is based on materials provided by University Of Texas Southwestern Medical Center At Dallas. Note: Materials may be edited for content and length.


Cite This Page:

University Of Texas Southwestern Medical Center At Dallas. "New Contact-Lens Materials Will Revolutionize The Industry, UT Southwestern Researchers Report." ScienceDaily. ScienceDaily, 7 January 2002. <www.sciencedaily.com/releases/2002/01/020107074716.htm>.
University Of Texas Southwestern Medical Center At Dallas. (2002, January 7). New Contact-Lens Materials Will Revolutionize The Industry, UT Southwestern Researchers Report. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2002/01/020107074716.htm
University Of Texas Southwestern Medical Center At Dallas. "New Contact-Lens Materials Will Revolutionize The Industry, UT Southwestern Researchers Report." ScienceDaily. www.sciencedaily.com/releases/2002/01/020107074716.htm (accessed July 30, 2014).

Share This




More Health & Medicine News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Health Insurers' Profits Slide

Health Insurers' Profits Slide

Reuters - Business Video Online (July 30, 2014) Obamacare-related costs were said to be behind the profit plunge at Wellpoint and Humana, but Wellpoint sees the new exchanges boosting its earnings for the full year. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Concern Grows Over Worsening Ebola Crisis

Concern Grows Over Worsening Ebola Crisis

AFP (July 30, 2014) Pan-African airline ASKY has suspended all flights to and from the capitals of Liberia and Sierra Leone amid the worsening Ebola health crisis, which has so far caused 672 deaths in Guinea, Liberia and Sierra Leone. Duration: 00:43 Video provided by AFP
Powered by NewsLook.com
At Least 20 Chikungunya Cases in New Jersey

At Least 20 Chikungunya Cases in New Jersey

AP (July 30, 2014) At least 20 New Jersey residents have tested positive for chikungunya, a mosquito-borne virus that has spread through the Caribbean. (July 30) Video provided by AP
Powered by NewsLook.com
Xtreme Eating: Your Daily Caloric Intake All On One Plate

Xtreme Eating: Your Daily Caloric Intake All On One Plate

Newsy (July 30, 2014) The Center for Science in the Public Interest released its 2014 list of single meals with whopping calorie counts. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins