What Is Contrast Sensitivity and Why Does It Matter?

Contrast sensitivity is your ability to determine differences in color and shade, particularly in low light environments. It’s what lets you see that pedestrian dressed in dark clothes when driving after sunset or notice the edge of a dark gray curb against black tarmac.

Contrast sensitivity vision issues can dramatically impact day-to-day life and, sadly, often don’t get as much attention in eye health care as, say, shortsightedness, astigmatism, or eye disease. It’s a completely different thing from visual acuity, meaning that it’s possible to have excellent—even 20:20—vision, but have poor contrast sensitivity.

It can be easy to shrug off low light and night vision difficulty as a natural element of aging. Indeed, along with cataracts, it’s a common issue that affects many of us. But it shouldn’t be ignored, as it can be a symptom of various different eye problems.

What Reducing Contrast Sensitivity Looks Like

Low contrast vision problems often evolve slowly. This means you might not notice your eyesight getting worse. One minute you’re happily living your best life, the next you’ve tripped up a step because you didn’t see it, or you realize that you’re avoiding driving at night because you’ve lost confidence.

Other symptoms include:

• Difficulty reading text that’s a similar color to the background
• A reduced ability to judge distances
• Vision problems in low light, like reading or recognizing people’s faces
• Problems distinguishing objects with similar colors, such as a dark purse in a handbag or black socks on a black couch.
• Eye strain and/or headaches when concentrating on close-up tasks for long periods

Once you’re aware of the symptoms, you can appreciate how much these can negatively impact your life.

The Link Between Eye Disease and Loss of Contrast Sensitivity

Although problems with contrast sensitivity tend to evolve with age, it can also be indicative of another problem.

Contrast sensitivity loss due to cataracts is one of the most common. Pretty much all of us, if we live to a good age, will eventually get cataracts, and reducing contrast sensitivity goes hand-in-hand with their evolution. Other potential causes include:

• Glaucoma
• Age-related macular degeneration (AMD)
• Diabetic retinopathy
• Keratoconus
• Heredity conditions, like Retinitis pigmentosa and Albinism
• Neurological conditions that affect the optic nerve, such as Multiple Sclerosis
• Traumatic brain injuries

Testing for Contrast Sensitivity

Eye doctors have historically tested for decreasing contrast sensitivity using physical vision tools, such as the Pell-Robson Sensitivity Chart. This is a bit like the Snellen Chart used to test visual acuity, where you read black letters on a white background with rows of text that get smaller and smaller. The Pell-Robson version uses colored letters that gradually reduce in contrast. There’s also a similar option, known as a Mars Contrast Sensitivity Test, that uses the same approach.

Today, technology brings us more cutting-edge options that can test both visual acuity and contrast sensitivity at the same time. The Freiburg Visual Acuity and Contrast Test (FrACT) uses typeface, letters, pictures, color, and shade, and there are also app-based versions linked to a computer that offer similar functionality.

If your ophthalmologist is concerned that you’re exhibiting signs of reduced contrast sensitivity, they may use additional testing to further investigate. One example is electroretinography, which provides more detailed insight into your unique visual pathways.

Poor contrast sensitivity can have a profound effect on your life. From an increased fall risk to issues with safe driving, diagnosing and treating any underlying symptoms is an important element of overall wellness as other physical interventions, such as blood pressure control and cardiovascular health.

Contrast sensitivity is just something we evaluate during regular eye tests at the West Boca Eye Center. Find out more at https://www.westbocaeyecenter.com/services/routine-eye-care

Contrast sensitivity is your ability to see subtle differences in shade and color, especially in low light. Learn common symptoms, what can cause reduced contrast sensitivity, and how eye doctors test and treat it.

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