Something fishy about contact lens comfort!

The news keeps getting better for those taking Omega-3 supplements (known for its preventive effect on heart disease and stroke) with researchers now finding it can also help improve ocular comfort during contact lens wear

Essential to body functions like blood clotting and building cell membranes in the brain, Omega-3 fatty acids (most abundantly found in fish), must be supplied to the body through food or supplements. The researchers from the Brien Holden Vision Institute have found that the supplements significantly improved ocular comfort with and without contact lenses, both in the morning and evening, when ocular discomfort tends to be greater.

The research was selected as one of the nine most newsworthy presentations at the 2012 Annual Meeting of the American Academy of Optometry (AAO), the biggest event on the international optometric calendar, held this year in Phoenix, from 24-27 October 2012.

Lead researcher and Head of Clinical Research at the Institute, Dr Percy Lazon de la Jara says, “We found an improvement in ocular clinical signs and ocular comfort and reduction of ocular dryness after oral consumption of Omega-3 supplements with and without contact lenses. However, it did not stop the ocular comfort decline over the day. These results indicate that Omega-3 supplements are beneficial in improving ocular comfort and health. Further research is needed to determine appropriate dosage to boost potential benefits of essential fatty acids (Omega-3 and Omega-6) for the eye.”

Of the more than 100 million contact lens wearers worldwide as much as 50 per cent report some level of discomfort and an estimated 12 per cent of contact lens wearers discontinue using them because of issues related to discomfort. The findings of this research could have the potential to benefit a huge section of the contact lens wearing population. Dr Lazon de la Jara has directed a series of contact lens studies being presented at the conference, including all but the last presentation referred to below.

A second paper was also selected as one of the nine most newsworthy. Daniel Tilia, research optometrist, and his colleagues have been investigating the behaviour of contact lens wearers, particularly some of the effects of non-compliance with recommendations made by manufacturers and practitioners to ensure safe and hygienic wear contact lens wear.

The researchers looked to determine the association between non-compliance and contact lens case contamination and the influence of written patient instructions on contact lens case compliance. They found that rinsing cases with tap-water significantly increases the risk of contamination with Gram-negative bacteria, even with new dual-disinfection systems. The research suggests that effective communication of instructions can significantly improve user’s lens case hygiene compliance.

“We’ve known for a long time that rinsing cases with tap-water is associated with increasing the risk of contamination with a bug called Acanthamoeba, but the risk of eye problems with this bug is quite low,” says Tilia. “However, rinsing cases with tap-water also increases the risk of contamination with bugs that are more likely to cause eye problems. Many patients continue to use tap-water to rinse cases. We need to convince them to use their lens care solution instead.”

The Institute, which has a long history in contact lens research, is also investigating whether ethnicity plays a role in contact lens wear.

Caucasians and Asians are two of the largest groups of contact lens wearers in the world, but is there any difference between the groups and their experience of contact lens wear? A recent analysis has asked that question and analysed the differences in physiological response and the clinical performance of lenses between the two ethnic groups.

A retrospective analysis conducted by research optometrist, Jerome Ozkan, and his colleagues, suggest that ethnicity does influence contact lens performance (in terms of lens fitting characteristics, subjective responses and wearing time) and may play a role in the incidence of significant corneal inflammatory events. The researchers recommend that this should be considered by practitioners and manufacturers to achieve a more successful fitting outcome and ultimately greater comfort and safety for the wearer.

Another presentation compares daily wear and daily disposable lenses for adverse events and subjective comfort. Results suggest that daily disposables or the use of peroxide in daily wear lenses should be the first choice for reducing corneal infiltrative events, such as infiltrative keratitis. Associate Professor Eric Papas commented, “Studies like this one provide an evidence base for clinical decision making and are essential to helping practitioners understand the value of different approaches to patient care.”

Researchers also suggest that wearing daily disposable lenses results in improved comfort at the end of the day. Studies conducted by research optometrist Jennie Diec and colleagues at the Institute found that amongst the participants using daily wear lenses, those using peroxide reported increased comfort upon inserting the lenses.

The final study presented at the AAO revisits the seminal work of Professor Brien Holden and Dr George Mertz in 1984, which determined the amount of oxygen transmissibility needed to produce the same level of overnight corneal swelling as that which occurs when no contact lens is worn. The improvements in contact lenses over the last 28 years has allowed researchers to provide better estimates of the oxygen transmissibility required to produce the same level of overnight central corneal swelling as that occurring in non-lens wearing eyes.

Find out more about the American Academy of Optometry: www.aaopt.org