By Dr. Itua Enakhe (OD)
Standard eye exams often focus on visual acuity — how clearly you can see sharp letters on a chart. However, they don’t always reveal how well your eyes detect objects against backgrounds with little contrast, such as gray text on white or objects in dim lighting. At SpecSMART Eye Clinic Ikoyi and Ikeja, Lagos, the Contrast Sensitivity Test offers deeper insights into your visual function, ensuring accurate diagnoses and personalized care.
What Is Contrast Sensitivity?
Contrast sensitivity is your ability to distinguish an object from its background when the contrast is low. It complements visual acuity by measuring vision in realistic conditions — like fog, dusk, or shadows — that can challenge everyday activities even if you have 20/20 vision.
People with normal sharpness may still have trouble seeing in low contrast, impacting night driving, reading, or navigating uneven surfaces.
How is Contrast Sensitivity Tested?
Several testing methods are used, including:
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Pelli-Robson Chart: Letters arranged in rows decreasing in contrast rather than size.
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CSV-1000 Test: Uses striped patterns with different spatial frequencies and contrast levels.
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Mars Letter Contrast Test: Similar to Pelli-Robson with progressively lighter letters.
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Digital Tests: Computer-based, providing precise analysis in clinical or research settings.
These tests help detect if contrast sensitivity is impaired and guide treatment.
Why Contrast Sensitivity Matters
Good contrast sensitivity is vital for:
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Safe Driving: Detecting pedestrians, signs, and vehicles under fog, rain, or nighttime conditions.
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Comfortable Reading: Especially in dim light or with low contrast print.
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Object Detection in Low Light: Recognizing faces or objects in shadows or poor lighting.
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Navigating Environments: Identifying steps, curbs, or obstacles to prevent falls.
Eye Conditions That Affect Contrast Sensitivity
Reduced contrast sensitivity can signal or accompany various eye diseases:
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Cataracts cause glare sensitivity and blurry vision.
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Glaucoma reduces peripheral vision and contrast perception.
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Age-Related Macular Degeneration affects central vision and detail discrimination.
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Diabetic Retinopathy causes fluctuating vision and glare issues.
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Keratoconus distorts corneal shape impacting contrast.
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Refractive surgeries may temporarily reduce contrast sensitivity.
Who Should Take This Test?
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Individuals struggling with night vision or glare.
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Patients with known eye diseases like glaucoma or cataracts.
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People post-refractive surgery.
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Athletes, pilots, or those needing optimal vision.
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Older adults at risk of falls.
Improving Contrast Sensitivity
If reduced, strategies include:
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Specialized lenses enhancing contrast.
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Better ambient and task-specific lighting.
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Medical or surgical treatment for underlying diseases.
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Nutritional support with antioxidants and carotenoids.
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Visual training exercises in some cases.
Conclusion
The Contrast Sensitivity Test provides essential insights beyond traditional eye exams, helping detect vision problems early and tailor treatment. At SpecSMART Eye Clinic Ikoyi and Ikeja, Lagos, advanced testing enables expert care for enhanced vision quality and safety in daily life.
Schedule a comprehensive eye exam today to protect your vision.
FAQs
What is the difference between contrast sensitivity and visual acuity?
Visual acuity measures sharpness under high contrast, while contrast sensitivity evaluates the ability to see objects against similar backgrounds or low contrast.
Can I have normal vision but poor contrast sensitivity?
Yes, poor contrast sensitivity can impact everyday vision despite having 20/20 acuity.
Is the contrast sensitivity test painful?
No, it is a simple, non-invasive test involving reading letters or patterns of varying contrast.
How often should I have a contrast sensitivity test?
It is recommended if you experience vision problems, have eye diseases, or after refractive surgery, or as advised by your optometrist.
📍Contact SpecSMART Eye Clinic Ikeja
Ile-Oja Mall, Opebi Link Road, Ikeja, Lagos
📞 0703 839 1197