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Special tinted contact lens on colour-defects
H A Mutilab1, Sharanjeet-Kaur, L K Keu
1Department of Optometry, Faculty of Allied Health Sciences, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia. haliza@medic.ukm.my
La Clinica Terapeutica
|September 12, 2012
Summary
Special red tint contact lenses did not impair visual acuity or contrast sensitivity in individuals with colour vision deficiency. However, stereopsis was negatively affected, and colour vision tests showed mixed results.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- Congenital colour vision deficiency affects a significant portion of the population.
- Specialized tinted contact lenses are sometimes used to aid individuals with colour vision deficits.
Purpose of the Study:
- To evaluate the impact of special red tint contact lenses on the visual functions of individuals with congenital colour vision deficiency.
- To assess changes in visual acuity, contrast sensitivity, and stereopsis with and without tinted lenses.
Main Methods:
- Seventeen subjects with congenital colour vision deficiency (14 deutans, 3 protans) participated.
- Visual functions including visual acuity (LogMAR), contrast sensitivity (FACT Chart), and stereopsis (TNO, Howard Dolman tests) were measured.
- Two types of red tint contact lenses (Type I light, Type II dark) were evaluated.
Main Results:
- No significant changes in visual acuity or contrast sensitivity were observed with either lens type.
- Stereopsis showed no significant change with the Howard Dolman test but was significantly poorer with the TNO test when wearing the lenses.
- Ishihara plate tests showed improved pass rates (88%) with lenses, while D15 and FM100Hue tests indicated persistent colour vision deficits.
Conclusions:
- Red tint contact lenses do not reduce visual acuity or contrast sensitivity in colour-deficient individuals.
- Stereopsis remains largely unaffected, except for a decrease in performance on the TNO test.
- While Ishihara plate performance improves, these lenses do not enhance colour discrimination on more sensitive tests like the FM100Hue.
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