Is Night Blindness the Same as Astigmatism?

Many people notice vision problems that seem worse at night - glare from headlights, halos around lights, or difficulty seeing clearly in low-light settings. Two common terms often come up in these situations: night blindness and astigmatism. While they can feel similar, they are not the same condition. Understanding the difference is key to getting the right diagnosis and treatment.

What Is Night Blindness?

Night blindness, also called nyctalopia, is not a disease on its own. It’s a symptom that makes it difficult to see in dim light or at night. People with night blindness may struggle with driving after dark, walking in poorly lit areas, or adjusting when moving from bright to dark environments.

Night blindness can be caused by several underlying issues, including:

• Vitamin A deficiency

• Retinal conditions such as retinitis pigmentosa

• Cataracts

• Certain eye diseases or systemic health conditions

Because night blindness often signals an underlying problem, a comprehensive eye exam is essential to identify the root cause.

What Is Astigmatism?

Astigmatism is a common refractive error caused by an irregular shape of the cornea or lens. Instead of being perfectly round, the eye is shaped more like a football, which prevents light from focusing evenly on the retina.

Common symptoms of astigmatism include:

• Blurred or distorted vision at all distances

• Eye strain or headaches

• Difficulty seeing fine details

• Increased glare or halos around lights, especially at night

Astigmatism can exist on its own or alongside nearsightedness or farsightedness, and it is typically corrected with glasses, contact lenses, or refractive surgery.

Why They’re Often Confused

Astigmatism can make night vision worse, particularly when it comes to glare from streetlights or oncoming headlights. This overlap in symptoms leads many people to assume they have night blindness when the issue is actually uncorrected astigmatism.

The key difference is this:

• Night blindness is a symptom caused by an underlying condition.

• Astigmatism is a structural refractive error of the eye.

Only a thorough eye exam can determine which one - or whether both - are affecting your vision.

How an Eye Exam Helps

A comprehensive eye exam in Stone Oak measures refractive errors such as astigmatism, helping determine whether blurred or distorted vision is caused by the way light enters the eye. It also evaluates overall eye health and retinal function, allowing your eye doctor to assess how well your eyes are working in both bright and low-light conditions.

During the exam, early signs of cataracts or other eye conditions can be identified, often before noticeable symptoms develop. Based on the findings, your eye care provider can recommend the most effective treatment options to improve night vision and overall visual comfort. Early detection not only improves visual clarity but also plays an important role in protecting your long-term eye health.

Take the Next Step at Eyes of San Antonio

Night blindness and astigmatism are not the same, even though their symptoms can overlap - especially at night. Astigmatism affects how light focuses in the eye, while night blindness points to an underlying condition that needs medical attention. If you’re noticing worsening vision after dark, the best next step is a professional eye evaluation to uncover the true cause.

If night driving feels stressful or your vision seems worse in low-light settings, don’t ignore it. Schedule a comprehensive eye exam with Eyes of San Antonio to get clear answers and personalized care for your vision. We proudly serve eye care in Stone Oak, San Antonio, TX. Call us at (210) 366-1021 to book an appointment today.