Double vision, also known as diplopia, can be a worrying and uncomfortable experience. Seeing two images instead of one can make everyday tasks like reading, driving, and even walking difficult. But what causes double vision? And is it something you should be concerned about? In this blog post, we'll explore the possible causes, why it happens, and what you should do if you're experiencing it.

Understanding Double Vision

Double vision occurs when you see two images of a single object. It can happen in one eye (monocular diplopia) or both eyes (binocular diplopia). The cause depends on which type you're experiencing, but either way, it’s a sign that something is affecting how your eyes are working together or how your brain processes visual information.

Let’s dive into the causes, starting with the less serious reasons before exploring more complex causes that might need medical attention.

Monocular Double Vision

Monocular double vision is better termed ghosting. It is due to a problem of focus within one eye. Even if you cover the unaffected eye, you still see two images with the other eye open.

1. Astigmatism

Astigmatism is a common cause of monocular double vision. It occurs when the cornea, the clear front part of the eye, is irregularly shaped. Instead of focusing light evenly, it creates distorted or double images.

2. Dry Eyes

Dry eyes can lead to irregularities on the surface of the eye, causing ghosting of images. Without enough moisture, the cornea becomes irritated, and your vision may suffer.

Monocular double vision or ghosting can often be helped by corrective glasses or contact lenses or ocular lubricants. It is not treated with double vision surgery.

Binocular Double Vision

Binocular double vision occurs when both eyes are involved. If you cover either eye, the double vision usually goes away. The problem arises when your eyes don’t align properly.

1. Eye Muscle Issues

If the muscles controlling your eye movement aren’t working together, your eyes can become misaligned. This misalignment causes your brain to receive two different images, resulting in double vision.

Common conditions include:

• Strabismus: A condition where the eyes don’t align correctly. One eye may turn in, out, up, or down.
• Nerve Palsy: Damage to the nerves controlling the eye muscles can also cause misalignment.

A common cause of Nerve Palsy is Diabetes. Diabetes can damage nerves by reducing their blood supply. Diabetic neuropathy (nerve damage) can lead to weakness in the muscles that control the eyes, resulting in poor alignment and double vision.

2. Other neurological Conditions

Sometimes, double vision is a symptom of a neurological or brain issues. Conditions that affect the brain and nervous system, such as multiple sclerosis, stroke, or brain tumours, can lead to double vision.

• Stroke: A stroke can damage the part of the brain that controls eye movement, leading to double vision. It’s crucial to seek immediate medical attention if double vision occurs suddenly alongside symptoms like weakness, slurred speech, or confusion.
• Multiple Sclerosis (MS): MS damages the nerves in the brain and spinal cord, which can affect how the eyes move and focus together.
• Brain Tumours: In some cases, a tumour can press on the nerves responsible for eye movement, causing double vision.

When to See a Doctor

Double vision isn’t something to ignore. Monocular double vision (ghosting) is relatively harmless and can be treated by an optician. Binocular double vision howeveris serious and can indicate serious health problems. If you suddenly experience double vision, especially if it’s accompanied by other symptoms like headaches, weakness, or difficulty speaking, seek immediate medical attention.

For ongoing or recurring double vision, it’s essential to see an eye specialist. They can diagnose the underlying cause and recommend the best treatment options to restore your clear vision.

With the right diagnosis, many causes of double vision can be treated effectively, allowing you to get back to seeing clearly.

Book a Free Appointment

If you're experiencing double vision (not ghosting), don’t wait to seek help. Book a free appointment today with an eye specialist to get to the bottom of what’s causing your symptoms and find the right solution for you.

Double vision can be caused by a variety of factors, ranging from simple conditions like dry eyes to more serious issues like neurological problems. Understanding what’s behind your double vision is the first step toward clear vision again. Whether it's a minor issue or something that requires more in-depth treatment, getting a diagnosis is crucial. If you're experiencing double vision, book a free appointment now to start your journey to clearer sight.