May 17, 2009
1 min read

Haploscopic filter contact lenses improve color perception in dyschromatopic patients

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NUSA DUA, Indonesia — By using colored haploscopic filter contact lenses, researchers were able to improve color perception in congenital dyschromatic patients, a presenter said here.

Ahmet Girgin, MD
Ahmet Girgin

"The normal human eye can perceive 10,000 different colors. Dyschromatopic patients can only see 2,000 colors," Ahmet Girgin, MD, explained during the joint meeting of the Asia-Pacific Academy of Ophthalmology and the American Academy of Ophthalmology. "After the therapy, dyschromatopic patients could perceive 6,000 different colors. As a result, the perception of the patient can be enhanced up to three times."

Dr. Girgin and colleagues studied 50 consecutive patients between January 2005 and March 2007. All of the patients, who happened to be male, complained of color perception deficit and were fitted with haploscopic Turkish Kromatik lenses (Tech Lens/Rainbow).

The researchers measured color deficiency with Ishihara tests before and after lens use, and the patients had both eyes fitted, and the color filter is placed in front of the nondominant eye.

In all patients, Ishihara scores increased. Before, the patients had an average score of 0.32 and afterward they had an average score of 0.89, a statistically significant difference.

"We changed the percentage of the colors received by the nondominant eye," Dr. Girgin said. "While the dominant eye sees the colors as usual, in the nondominant eye, color perception improves dramatically."