Contrast Sensitivity

OVERVIEW

A Contrast Sensitivity Test measures how well your eyes can distinguish between light and dark shades, especially when the difference between them is small. Unlike a standard visual acuity test that checks how clearly you see black letters on a bright white background, this test evaluates how well you see objects that do not stand out clearly from their background. It helps detect visual problems that may not appear in routine eye chart testing.

WHY THIS TEST IS IMPORTANT

Many real-world visual tasks depend on contrast sensitivity rather than simple sharpness of vision. Examples include seeing pedestrians at dusk, reading low-contrast print, recognizing faces in dim lighting, and driving in fog or rain. A person may have “20/20” vision on a chart but still struggle with low-contrast situations.

Reduced contrast sensitivity can occur in several eye and medical conditions, including:

• Early cataracts
• Glaucoma
• Macular disease
• Diabetic eye disease
• Corneal disorders
• Dry eye disease
• After refractive or cataract surgery
• Certain neurologic conditions

Testing provides additional information that supports accurate diagnosis and treatment planning.

HOW THE TEST IS PERFORMED

The Contrast Sensitivity Test is noninvasive and painless. You will be asked to look at a chart or digital display showing letters, numbers, or patterns that gradually become lighter and harder to see against the background. You identify the symbols as they fade in contrast.

The test is typically performed:

1. With your current eyeglasses or contact lenses
2. One eye at a time, then both eyes together
3. Under standardized lighting conditions

The procedure usually takes only a few minutes to complete.

WHO SHOULD HAVE THIS TEST

Contrast sensitivity testing is especially useful for:

• Patients with visual complaints despite good visual acuity
• Individuals with cataracts or suspected early lens changes
• Patients with retinal or optic nerve disease
• Those reporting night vision or low-light driving difficulty
• Pre- and post-operative assessment for selected eye surgeries
• Contact lens and refractive surgery evaluations

WHAT THE RESULTS MEAN

Your results show how well you detect decreasing levels of contrast. Lower-than-expected scores may explain symptoms such as hazy vision, glare sensitivity, or difficulty seeing in dim environments. Your eye care professional will interpret the findings together with your full eye examination and other diagnostic tests.

LIMITATIONS AND CLINICAL USE

Contrast sensitivity testing is an adjunct diagnostic tool. It does not replace a complete eye examination or standard visual acuity testing. Results must be interpreted in proper clinical context. Management decisions are based on the totality of clinical findings, not on this test alone.

This service is part of a comprehensive, evidence-based eye evaluation designed to better understand your functional vision in everyday conditions.