Brief overview
- Causes: Fatigue, stress, alcohol, eye disease, strabismus, injury, paralysis, certain diseases such as diabetes or multiple sclerosis.
- What is diplopia: Seeing double images
- Symptoms: Sudden or gradual double vision, dizziness, disorientation, in severe cases pain
- When to see a doctor: If diplopia does not disappear by itself after a short time, a doctor should be consulted immediately.
- Diagnosis: Examination by an ophthalmologist and orthoptist.
- Treatment: Depending on the particular cause or underlying disease.
- Prevention: Healthy lifestyle (balanced diet, avoidance of nicotine and alcohol, sufficient sleep).
Why am I suddenly seeing double?
When people suddenly see everything twice, it is often for harmless reasons. For example, they are very tired or have been working at a computer screen for a long time. In these cases, the double vision disappears again by itself after a period of rest. Migraine, stress or too much alcohol consumption are also sometimes triggers for temporarily seeing double.
Monocular double vision (double image in one eye): Monocular means “pertaining to only one eye” (Latin “mono-” for singular, single, alone and Greek “oculus” for eye). Monocular double vision persists even when affected individuals cover one eye. In this form of double vision, the problem lies in the eyeball, which reacts to light. Normally, the cornea and crystalline lens work together to ensure that light rays entering the eye are focused and converge on a single point on the retina (macula, site of sharpest vision). If the light hits next to it, those affected see a blurred or distorted image. This is the case with various eye diseases:
- Farsightedness or nearsightedness (e.g. due to missing or wrong glasses)
- Diseases of the cornea (e.g. astigmatism)
- Opacities of the lens (cataract)
- Compression of the lens nucleus (cataract)
- Displacement of the lens
- Retinal diseases (e.g., vascular occlusion in one or more vessels supplying blood to the eye)
- Dry eye
Double images in both eyes occur when the eyes are not aligned parallel. This causes the brain to no longer completely combine the visual impressions of both eyes into one image. Binocular double images occur when the eye muscles do not work properly. The reasons for this may be harmless, such as lack of sleep or excessive alcohol consumption, and disappear again on their own. However, there may also be serious causes behind it.
If the eye muscles no longer function properly, the cause is either in the eye itself or it is caused by diseases outside the eye. The following eye diseases can cause binocular double vision:
- Strabismus (squint)
- Inflammation of the eye muscles
- Diseases of the eye muscles
- Tumor diseases of the eye
Other known triggers for binocular double vision include injuries or damage to the brain:
- Stroke: In a stroke, a blood clot forms, causing certain areas of the brain to lose blood supply. If nerves that control the eyes are damaged, this results in
- Head injuries (such as a fracture of the eye socket).
- Vessel dilation in the brain (brain aneurysm): In an aneurysm, a blood vessel is bulging. If this presses on the nerve of the eye muscle, those affected may see double.
- Cranial nerve paralysis: Triggers can be neurological diseases such as multiple sclerosis, myasthenia gravis or Lyme disease.
Diseases that affect the entire body are also sometimes the cause of double vision:
- Endocrine orbitopathy: Triggered by a thyroid disease, an inflammatory disease of the eye socket occurs.
- Circulatory disturbances as a result of diabetes or high blood pressure.
What are the symptoms of diplopia?
Whoever perceives one and the same object blurred or double, i.e. (slightly) horizontally, vertically or obliquely shifted, sees double. Double vision occurs suddenly (acute diplopia) or gradually, in the distance or close up, or even just when looking to the side.
The following symptoms indicate serious causes and give the doctor first clues about the reason for the visual disturbance:
- Disturbances in eye movement
- Drooping of the upper eyelid
- Swelling of the eyelids
- Visible squint
- Protruding eyes
- Pain during eye movement
Although diplopia “only” affects the eyes, seeing double images has far-reaching effects on the daily lives of those affected: Those who do not see clearly (anymore) injure themselves more easily. Affected people fall more often or injure themselves for seemingly inexplicable reasons.
Possible effects of diplopia are:
- Heights, depths and distances are no longer correctly estimated. (Risk of injury!)
- Affected persons miss or bump into each other.
- Unsteady walking, especially when climbing stairs
- Difficulty reading
- Dizziness
- Headaches
- Blurred vision
Consult an ophthalmologist immediately if you notice any of the above symptoms!
What is diplopia?
Diplopia is a form of vision disorder in which affected persons see double images. They perceive a viewed object as two objects displaced against each other.
In double vision, the coordination of the eyes is disturbed. The two images are no longer completely merged, but appear shifted next to or on top of each other. The causes of diplopia are manifold; they can be harmless, but also an indication of a serious disease.
Double vision makes it difficult for sufferers to see the environment correctly: Heights, depths and distances are misjudged. Affected persons suddenly have orientation difficulties, reach past objects or have problems walking. If diplopia occurs, an ophthalmologist should be consulted. He or she will determine whether it is a harmless, temporary visual disorder or whether a serious illness is behind it.
If you have double vision, do not drive yourself! Have a trusted person take you to the doctor or, if necessary, to the emergency room!
When to see a doctor?
Double vision is a common visual disorder that often disappears on its own after a short time. In some cases, diplopia hides a more serious condition. It is therefore always advisable to consult an ophthalmologist if the double vision persists for a longer period of time.
- You have eye pain.
- One eye or both eyes are protruding.
- You have recently had a head injury.
- The double vision does not go away even after covering one eye (binocular double vision).
- There are accompanying symptoms such as weakness, facial paralysis, problems speaking, swallowing, walking, dizziness, headache, incontinence.
Double vision should always be examined by an ophthalmologist, even if it disappears on its own. If they occur suddenly and are accompanied by other symptoms such as pain or paralysis, it is an emergency!
What does the doctor do?
The first point of contact for double vision is the ophthalmologist and, if necessary, the orthoptist. While the ophthalmologist examines the visual abilities, the orthoptist deals with the eye position, the mobility of the eyes and their interaction.
Examination by the ophthalmologist
To make a diagnosis, the ophthalmologist first inquires closely about the symptoms to find clues to possible causes. He will ask the following questions:
- How long have you been seeing double vision?
- Do you have pain?
- Are you currently seeing double vision?
- Was there a trigger? (Injury, surgery, new glasses)
- Do the double images disappear when you cover one eye?
- Are the double images always there or only temporarily?
- Do the double images appear horizontally, vertically, obliquely or tilted?
- Do the double images change with the direction of gaze or head position?
- Do the images change during the day?
- Do you experience other symptoms such as headaches, eye pain, eye movement pain, eye redness, hearing disturbances, sensory disturbances, dizziness, and/or gait unsteadiness?
- Have you been diagnosed with another condition such as diabetes or multiple sclerosis?
- Did you have crossed eyes as a child?
He then examines both eyes in detail – regardless of whether the double vision occurs in one or both eyes. The doctor checks the vision, the mobility of the eyes and the reaction of the pupils to light. At the same time, he looks for changes such as protruding eyes or droopy eyelids.
By covering one eye at a time, the ophthalmologist also determines whether the double vision affects only one eye or both eyes. This provides further clues in the search for the cause of diplopia.
Examination by an orthoptist
If the doctor detects binocular diplopia, a so-called orthoptic examination usually follows. Orthoptics is a specialty of ophthalmology that deals specifically with eye movement disorders. The orthoptist checks whether affected persons squint, see three-dimensionally and whether both eyes work together properly. Following the examination, the orthoptist discusses further procedures with the patient and the ophthalmologist.
Further examinations
Since diplopia can have many causes, further examinations are often necessary for a reliable diagnosis. These include imaging procedures such as magnetic resonance imaging or computer tomography. They make changes in the eye level, the skull or the brain visible.
If there is a suspicion that the diplopia is due to, for example, diabetes mellitus or another general disease (circulatory disorder), he or she refers the patient to an internist. Once all examinations are complete, the physician discusses the findings with the patient and initiates the appropriate treatment for the patient.
Treatment
How diplopia is treated depends on the underlying cause. With the treatment of the underlying disease, the double vision usually disappears.
Treatment of monocular double vision
Monocular double vision is usually caused by an eye disease, which the ophthalmologist treats accordingly:
Presbyopia: The doctor compensates for nearsightedness or farsightedness with appropriately fitted glasses or contact lenses.
Corneal curvature: With a laser treatment, the doctor changes the cornea so that the retina produces a sharp image again. Visual acuity is restored and double vision disappears.
Cataract: If the lens is clouded, affected individuals see “as if through a veil.” During cataract surgery, the doctor replaces the lens with an artificial lens.
Treatment of binocular double vision
Treatment of the underlying disease
In binocular double vision, the eye itself is not diseased, but the diplopia is a consequence of another disease. Depending on the particular cause, the doctor will start the appropriate therapy. If the treatment is successful, the double vision will also improve.
If the diplopia is caused by other diseases such as migraine or multiple sclerosis, the doctor will treat them with special medication. The same applies to circulatory disorders or thyroid diseases. The better the disease is under control, the less the effects on vision.
Double vision that occurs suddenly and is accompanied by paralysis or pain is an alarm signal. In these cases, the cause must be clarified and treated by a doctor as soon as possible.
If the double images do not disappear again despite proper treatment, special glasses are used. These are coated with foils that focus the incident light beam so that the affected person only sees one image. Alternatively, eye patches or eye patches are used to alleviate the symptoms.
Eye exercises
- Focus on a specific target such as a photograph.
- Hold the image at eye level an arm’s length away.
- Try to see only one image for as long as possible.
- Move the photo slowly and steadily toward your nose.
- Stop as soon as the single image becomes two images and return to the position where you last saw one image.
- Start the exercise again.
Can diplopia be prevented?
Diplopia can have many causes. Accordingly, there are many ways to prevent double vision.
Since diplopia is often triggered by other underlying diseases such as diabetes or high blood pressure, a healthy lifestyle is the first priority for prevention. A balanced diet, sufficient sleep and low stress do not reliably prevent double vision, but they minimize the risk. The same applies to accidents. Here, appropriate measures (protective goggles, wearing a helmet) protect against head and eye injuries.
