If you typically clean and then air dry your contact lens case, researchers say you could risk contamination if you leave it face up.

A study published in the July issue of Optometry & Vision Science says small numbers of microorganisms were found in contact lens cases when they were cleaned and then left in a face up position.

Contamination was even more likely in humid environments when cases were left face up after cleaning.

“On the basis of this limited study, we would recommend contact lens cases be air dried face down,” researchers said.

Based on these recent findings about care of contact lens cases, Contact Lens Headlines editorial advisor Edward Bennett, OD, MSEd, also suggests that wearers can be extra safe if they replace lens cases frequently — as often as monthly and at least every three months.

Bennett is executive director of the Gas Permeable (GP) Lens Institute (Contact Lens Manufacturers Association). He also is co-chief of the Contact Lens Service at the University of Missouri - St. Louis College of Optometry, where he is an associate professor.

Bennett offered two other crucial tips about good hygiene and contact lens cases:

• Use fresh disinfecting solution daily to minimize contamination of the soaking solution.

• Use only contact lens care products (for cases and contacts) recommended by your eye care practitioner.

“The importance of the lens case in successful, healthy contact lens wear cannot be overemphasized,” Bennett said. “Bacteria and other microorganisms in a nutrient-deprived environment, such as a contact lens case, can secrete a kind of slime which can protect the bacteria against certain preservatives.”

Many contact lens wearers fail to replace their lenses on time, don’t remember the name of their contact lens solutions and don’t replace their contact lens storage case when it gets old and dirty.

These are some of the findings of a new study conducted by researchers at the Centre for Contact Lens Research (CCLR) at the University of Waterloo (Ontario, Canada).

A total of 158 U.S. eye care practitioners assisted in the study by distributing surveys to their contact lens patients. A total of 1,654 of the returned patient surveys were eligible for analysis.

The mean age of contact lens wearers in the study was 34 years (range: 14 to 79 years). The majority wore their lenses on a daily wear basis, but 12 percent reported wearing extended wear contact lenses on a continuous basis.

Among the results of the study:

• 16 percent of participants wore daily disposable contacts; 45 percent wore 2-week replacement silicone hydrogel contact lenses; 39 percent wore 1-month replacement silicone hydrogel lenses.

• 20 percent of participants were unsure of the type of contact lenses they were wearing.

• 52 percent of those wearing 2-week disposable contact lenses, 28 percent of those wearing 1-month replacement lenses and 12 percent of those wearing daily disposable lenses did not replace their contacts on a timely basis.

• The overall rate of patient noncompliance with the replacement frequency recommended by their eye doctor was 38 percent.

• When asked about their lens care regimen, 40 percent could not recall or did not know the name of their contact lens care products.

Generally, contact lens cases should be replaced at least every 3 months, but only 50 percent of the study participants reported doing so. A total of 20 percent reported replacing their case every 6 months, 16 percent said they replaced their case annually and 14 precent aid they had never replaced their lens storage case.

The researchers also found that end-of-day contact lens discomfort was reported by a higher proportion of contact lens wearers (51 percent) who failed to replace their contact lenses on time.

A full report of the study appears in the June 2010 issue of Contact Lens Spectrum.

Need another reason to quit smoking? How about because it might make your contact lenses feel better and decrease your risk of eye problems?

Researchers at Case Western Reserve University (Cleveland, Ohio) recently fit 205 patients with CIBA Vision’s Night & Day silicone hydrogel contact lenses for continuous wear and followed them for a period of one year. The purpose of the study was to identify risk factors associated with the development of corneal infiltrates during extended wear of the lenses.

Corneal infiltrates are small, hazy, gray-appearing areas that appear in the clear front surface of the eye (cornea) as evidence of inflammation. They are composed of inflammatory cells such as white blood cells, and typically appear in the periphery of the cornea, often under the upper eyelid.

Symptoms of corneal infiltrates include a foreign body sensation (feeling something is “in” the eye), red eyes, excessive tearing, sensitivity to light and contact lens discomfort.

The researchers found that smokers who wore the Night & Day contact lenses on a continuous basis had greater than four times the risk of developing corneal infiltrates, compared with non-smokers.

Treatment options for corneal infiltrates include discontinuing contact lens wear, use of topical antibiotics (to treat or reduce the risk of infiltrate-associated eye infections) and/or use of topical anti-inflammatory medications.

A full report of the study was published on the Investigative Ophthalmology & Visual Science website on June 10, 2010.

New specially designed silicone hydrogel contact lenses may slow the progression of myopia in pre-teen and teenage children.

That’s the conclusion of researchers from Australia, China and the United States, who presented the findings of a new study at the recent annual meeting of the Association for Research in Vision and Ophthalmology (ARVO).

The researchers compared the progression of myopia among Chinese schoolchildren for a period of 6 months. All children in the study were between the ages of 7 and 14 at the beginning of the study period, and had –0.75 to –3.50 diopters (D) of myopia with no more than 0.50 D of astigmatism.  A total of 65 children wore the experimental contacts, and 50 children wore eyeglasses.

The contact lenses were designed to fully correct the wearers’ central vision and reduce the relative peripheral hyperopia produced by conventional corrective lenses, which some researchers feel may be a cause of myopia progression.

At the end of the 6-month study period, the children wearing the experimental contact lenses had 54 percent less progression of their myopia than the children wearing eyeglasses.

The researchers said the study results are promising with regard to the development of a new generation of contact lenses aimed at myopia control, but additional study of the contacts over longer periods of time is needed to fully judge their effectiveness.