Extended Wear Soft Contact Lenses

A unique global collaboration between an Australian Cooperative Research Centre and an international eye-care company led to the creation, in 1999, of ‘contact lenses that breathe.’ For many, the development has ended the need for daily contact lens insertion, removal and care, and has meant less need to carry cases and solutions everywhere, not to mention savings on cleaning and disinfecting solutions.

Australian cooperative research centre for eye research and technology (CRCERT, or Vision CRC), based at the University of New South Wales, took an interest in the development of soft contact lenses in the 1990s, when the only kind available was recommended for daily wear and discard. If not replaced regularly, these lenses had potentially cornea-harming effects due to a lack of oxygen transmission, particularly during sleep.

Soft contact lenses are hydrophilic or ‘water loving.’ Their water content ranges from 38% to 75% for different applications. They provide increasing oxygen transmission but less durability as the water content raises. In 1999, in association with international eye-care company CIBA Vision, a CRCERT team led by Dr. Gordon Meijs from Australia’s science organisation CSIRO designed unique polymers and surfaces that allow the passage of oxygen to the eyes from the eyelid during sleep. The revolutionary polymeric material is capable of transmitting up to six times more oxygen to the eye than ordinary soft lenses. It was the unique combination of fluorine and siloxane that made up the winning formula, trade-named Lotrafilcon A.

The new lenses have allowed extended wear for up to 30 days and nights. Previously available lenses had limited oxygen permeability and had to be removed every night to ensure eye health. Moreover, this new vision-care technology means the wearer can get up in the middle of the night or wake up in the morning with the ability to see normally.

The new technology has addressed a rapidly growing vision care market, in which there are over 70 million contact lens users today compared with 1-2 million in 1970. Focus Night and Day lenses, as they have been marketed by CIBA, are now available in more than 40 countries. The Australian CRC’s portion of the proceeds from this research as well royalties from sales have enabled further vision research, education and care delivery.

Vision CRC and CIBA received a Business/Higher Education Round Table (B-HERT) Award for Outstanding Achievement in Collaborative R&D, and a Cooperative Research Centres Association Award for Technology Transfer for their achievement.