Differences in wettability among silicone hydrogel-solution combinations relevant

Issue: December/January 2013

SEATTLE – Properties that affect patients’ comfort with silicone hydrogel contact lenses are multifactorial and include wettability, which affects not only a patient’s comfort but also their visual performance, according to an investigator here.

Here at the American Academy of Optometry annual meeting, Sebastian Marx, Dipl-Ing, (FH) AO, OD, presented a study that compared surface wettability of combinations of 10 different silicone hydrogels with various contact lens solutions to the lens coming directly out of the blister pack. The lenses were made of balafilcon A, lotrafilcon B with Aqua technology, lotrafilcon A, comfilcon A and senofilcon A. Solutions tested included ReNu Refresh multipurpose solution (Bausch + Lomb), Opti-Free PureMoist (Alcon) and, as a control, Sensitive Eyes (Bausch + Lomb).

Marx described the procedure to test surface wettability. Investigators removed the lenses from the blister packages and washed and then soaked each lens in the contact lens solution for 24 hours. The noninvasive keratograph – drying-up time (NIK-DUT) was measured by taking the lens out of the solution using forceps, blotting it on special paper then placing it “onto a special stage.” The measurement time was started and stopped manually by the investigator, and the NIK-DUT was measured independently by special software, he said.

The test was done 10 times for each lens material-solution combination.

“There are significant differences in wettability between the tested contact lens material and test solutions. The wettability was higher for all lenses when they were presoaked in Opti-Free PureMoist,” Marx said. “Increasing lens wettability through the use of a wetting agent designed to interact with silicone material may have a positive impact on the patient’s lens wearing experience.” – by Joan-Marie Stiglich, ELS

Disclosure: This study was sponsored by Alcon Vision Care.