Double Vision (Diplopia)

If you begin to see double when your eyes typically work well, this is something that you should take seriously. Double vision, also known as diplopia, may only be a temporary condition but still warrants a visit to your optometrist to find out what is happening.

Common Causes

Temporary bouts of double vision can occur for several reasons, including fatigue and too much alcohol consumption. This type of short term issue is not usually a reason for concern. However, if your double vision last a long time or keeps returning, the reasons can include:

Brain tumor, stroke, aneurysm, head injury or brain swelling: Any of these things can be connected to your double vision; especially if it comes on suddenly. After your eyes are examined, your doctor may send you to a specialist (ex. Neurologist or neurosurgeon) for more tests and treatment.

Cataracts: If cataracts are the cause of ghost images it is typically only in one of the eyes, not both. The reason for this is that when they eyes lenses cloud, it makes the rays shoot off in all directions and creates many incomplete images. This is especially true when you look into the light. Cataract surgery will generally rid you of the problem of ghost images.

Corneal irregularities: This can cause ghost like images that may be connected to dystrophies or keratoconus. These images can sometimes be more difficult to manage and may be helped by wearing specialised contact lenses, using punctal plugs or eye drops, or in serious cases, surgery. Your doctor will help you decide what the best course of treatment is.

Cranial Nerve Palsies: Loss of eye coordination or paralysis can also cause double vision. The main issue here is palsy. Palsy in the cranial nerve can be caused by head injuries, diabetes, tumors, high blood pressure, meningitis, artery blockage or multiple sclerosis.

The majority of cranial nerve palsies will clear up without any treatment when your condition begins to improve. However, there are some people that might need surgery, glasses or vision therapy.

Dry eyes: Severe cases of dry eyes, like Sjogren's syndrome, can cause these ghost images because of poor tear quality. Those who have dry eyes can get help from punctal plugs, eye drops, lid hygiene and eye vitamins. These treatments can also be combined for the best effect. It is vital to have a workup and treatment in place for dry eyes. It is best to see a doctor that has experience and interest in this particular disorder because they will have kept up to date on the latest treatments methods.

Refractive Surgical Procedures: If you have had PRK or LASISK to see better without the use of eyeglasses or contact lenses, you might experience a bit of ghost imaging or double vision due to the corneal changes. A corneal surface that is irregular caused by dryness or surgery can cause the light to scatter around as opposed to focusing on objects properly. This will typically clear itself up in a few weeks or, at the very most, months, you just have to use some eye drops for a little while until it does. For some people, a second procedure may be necessary to overcome the issues.

Ghost Images

Instead of seeing a clear double image, it's possible you'll only see an incomplete or "ghost image" to the side or around what's in your line of sight, more so if you're looking a source of light or something bright.

Ghost images generally only affect one eye, like those caused by cataracts. Ghost images may occur after surgery of the corneal, particular types of surgery include PRK, LASIK and corneal transplant. Surgical problems, like ghost images will usually go away once the eye has had time to heal.

Double Vision and Eye Structure

Of course most people don't expect to see double. The truth is though that the ability to see just one image with both eyes involves a system of complex nerves, muscles and other parts of the eye.

When both eyes are accurately and correctly focusing on one point at the same time, you see just one image. When both eyes are focusing in different directions you see double. Some people come into the world with eyes that do not work properly together, and this condition is known as strabismus. It can cause the eyes to turn out or in and appear crossed or lazy. If you have this condition than you will likely see double if you brain will allow it to. However, the brain typically shuts down or ignores the information coming in from one of the eyes. This is known as suppression and therapy or surgery can correct the problem.

Treatments

The general treatment for double vision includes one of the following, or a combination of the following:

• Surgery
• Vision therapy
• Prism glasses
• Medications

It is vital that you have a full eye exam to find out the cause of your double vision before any treatment can take place. You may be required to see a specialist to diagnose and treat the issue.

If double vision pops up suddenly and then goes away for long stretches of time, your brain may be blocking out the images. Even though this is more comfortable for your vision, it is definitely not a positive sign. This visual suppression could be a cover up for more serious issues that needs to be solved. In fact, it may actually be a difference between life and death if it is caused by an aneurysm or tumor. See your optometrist if you develop double vision and do so as soon as possible.

There are some conditions that cause double vision that are extremely hard to fix. Some are even impossible. Some nerve palsies and strokes cause double vision to fluctuate and that cannot be measured accurately. This means that correction may not be possible. Under these circumstances you could need an adjustment period so you can learn how to live with those systems. Your optometrist can help you by prescribing special contacts or prisms, or patching one of your eyes. In the majority of cases the brain will suppress one image eventually so you can move on with your normal life. As with most changes in life, patience is a virtue when you have to deal with these types of problems.