Brief overview
- Causes of visual disturbances: e.g. short-sightedness, long-sightedness, migraine, eye diseases (such as age-related macular degeneration), optic neuritis, tumors, stress
- How do visual impairments manifest themselves? Depending on the cause, they can include flickering, flashing, restricted field of vision, “gnats”, “soot rain” or (temporary) blindness
- Treatment of visual impairment: depending on the cause, e.g. by means of vision correction (glasses, contact lenses), medication, surgery if necessary
Visual disturbances: Causes and possible diseases
There are many different causes of visual impairment. Comparatively harmless causes include
- Migraine with aura (e.g. flashes of light or flickering in front of the eyes, speech difficulties, discomfort)
- Acute hypoglycemia (e.g. flickering, “going black before the eyes”)
- Fatigue (e.g. seeing double images)
- dry eyes/overload/stress (e.g. twitching of the eyelid)
- Visual impairment (blurred vision at near or far)
However, there are also more serious causes of vision problems. These include, for example:
- Eye diseases: Diseases of the eye (ophthalmological causes) such as glaucoma, cataracts or retinal detachment are often to blame for visual disturbances.
- Vascular causes: These include, for example, lack of blood flow in the brain (as in migraine or a TIA – a common precursor to stroke), vascular occlusions in the retina and vascular spasms in pregnancy toxemia (pre-eclampsia).
- Space-occupying processes in the head: These can also be accompanied by visual disturbances, such as eye and brain tumors, cerebral hemorrhage, abscesses, vascular malformations (angiomas) and vascular bulges (aneurysms).
- Stress: Visual disturbances caused by stress are also possible, for example when prolonged physical and/or mental stress increases the concentration of stress hormones and damages the blood vessels in the eye.
- External violence: Optic nerve damage caused by external violence such as an accident (traumatic opticopathies) are also possible causes of visual impairment.
- Therapeutic consequences: Visual disturbances can also be permanent residual damage (residual conditions) from radiotherapy or chemotherapy as well as meningitis.
Important causes of visual disorders in detail
The most important triggers of visual disorders include
Short-sightedness (myopia): Short-sighted people only perceive close objects sharply, while their vision in the distance is blurred because their eyeball is too long. Incident rays of light therefore converge in front of the retina. Severe short-sightedness also favors a posterior vitreous detachment (see below), which causes further visual disturbances.
Presbyopia (presbyopia): Presbyopia develops in old age when the lens of the eye becomes less elastic. Here too, visual acuity for close objects is reduced.
Strabismus: If the eye deviates from the required direction of gaze, this is either due to paralysis of the eye muscles or has no identifiable cause. The main visual disturbance in strabismus is seeing double images (diplopia).
Age-related macular degeneration (AMD): Visual impairment due to AMD is widespread. Metabolic products accumulate in the eye, gradually destroying the center of the retina. In the case of so-called “dry AMD”, vision deteriorates as a result, while in the case of “wet AMD”, the affected person also has distorted vision. If left untreated, those affected will go blind.
If an attack of glaucoma is suspected (rapid, one-sided deterioration of vision to blindness with headache or eye pain), consult an ophthalmologist immediately!
Vitreous opacities: With age and short-sightedness, vitreous opacity can develop, which those affected usually perceive as “mouches volantes” (“flying gnats”) – these are gray, floating dots and threads. The clouding floats along with eye movements, but in the long term it subsides. “Mouches volantes” are annoying, but usually harmless. However, they can also occur with inflammatory eye diseases.
Vitreous hemorrhage: Bleeding into the vitreous body can be the result of a posterior vitreous detachment or diabetes-related eye disease (diabetic retinopathy), for example. They cause visual disturbances such as sudden dark clouding, which those affected often describe as “black flakes” or “soot rain”. Severe bleeding can also lead to a deterioration in vision and even sudden blindness.
See an ophthalmologist immediately if you notice any signs of vitreous opacity!
If a retinal detachment is suspected, consult an ophthalmologist immediately!
Manager’s eye disease: In this case, the visual disturbances are caused by stress – people who are under stress at work and/or at home over a long period of time are affected. Typical symptoms are changes in color vision, double vision, gray spots in the field of vision, blurred or distorted vision, often dry eyes, eyelid twitching or the compulsion to blink. The cause is presumably the increased concentration of the stress hormone cortisol in the blood, which can damage the blood vessels in the eye – up to and including retinal detachment – but also a genetically determined susceptibility.
Graves’ disease: This autoimmune disease is a common form of hyperthyroidism. In many patients, it leads to a characteristic eye disorder known as endocrine orbitopathy. Symptoms include protrusion of the eyes out of the eye socket, a foreign body sensation in the eye, photophobia, double vision and visual impairment, but dryness, redness or eyelid swelling can also occur with Graves’ disease.
Inflammation of the arteries (temporal arteritis): This disease causes inflammation of the arterial walls in sections, particularly of the temporal artery and the cerebral arteries. It mainly occurs after the age of 50. The chronic inflammation usually leads to an initial one-sided loss of vision. Within weeks, the second eye often also becomes diseased.
If there are signs of a vascular occlusion in the retina, call an emergency doctor or go to a clinic immediately!
A TIA is often the harbinger of a stroke. Call an emergency doctor immediately!
Widening of a cerebral artery (cerebral aneurysm): Constant or alternating double vision without any abnormalities in the eye is sometimes caused by a cerebral aneurysm, i.e. a widening of the cerebral artery. If it ruptures, there is a risk of a life-threatening cerebral hemorrhage.
If cerebral bleeding is suspected, call an emergency doctor immediately!
Brain tumor: Both benign and malignant brain tumors can cause visual disturbances depending on their size and location in the brain. For example, blurred vision, visual field defects, progressive visual deterioration and double vision may occur.
Pathological muscle weakness (myasthenia gravis): This severe form of muscle weakness is an autoimmune disease. Common initial symptoms are visual disturbances in the form of double vision and drooping of the upper eyelid when the eye is open.
Side effects of medication: Rare side effects of digitalis (heart medication), sulphonamides (antibiotics) and diuretics (diuretics) are visual disturbances in the area of color perception (yellow, red or blue vision).
If nausea, confusion or visual disturbances occur after treatment with digitalis, consult a clinic immediately!
Visual disturbances: Symptoms
There are different types of visual disturbances:
- Double vision (diplopia) can be caused by alcohol, disorders of certain cranial nerves or multiple sclerosis.
- Flashing/curtain vision occurs, for example, with a detached retina.
- Disturbing elements (soot rain, “flying mosquitoes” = mouches volantes) can indicate a retinal detachment or vitreous detachment, for example.
- Visual field defects (tunnel vision) are caused by glaucoma or tumors, for example.
- Disorders of color vision are either congenital (as in red-green deficiency) or acquired (for example due to a glaucoma attack or poisoning with digitalis).
Visual disturbances: Diagnosis
Various examinations can reveal the cause of visual disturbances, including in particular:
- Ophthalmologic examination: In the case of eye problems such as visual disturbances, an examination by an ophthalmologist is routine. Among other things, he or she checks the visual performance and can thus, for example, identify defective vision as the cause of the visual disturbances. Other examinations include a slit lamp examination, ophthalmoscopy and intraocular pressure measurement (see below).
- Ophthalmoscopy (ophthalmoscopy): Ophthalmoscopy can be used to examine the back of the eye. This is important, for example, if the doctor suspects a retinal disease (such as vascular occlusion) or an eye tumor as the cause of the visual disturbances.
- Intraocular pressure measurement (tonometry): This is mainly carried out if the doctor suspects glaucoma (glaucoma) is behind the visual disturbances.
- Neurological examinations: If certain neurological disorders or diseases (e.g. multiple sclerosis, optic neuritis) are a possible explanation for the visual disturbances, the doctor will check the condition and function of nerve pathways.
- Ultrasound examination (sonography): An eye ultrasound is indicated, for example, to clarify retinal detachment, eye tumors or optic nerve changes. In the case of visual impairment due to Graves’ disease, the doctor will also perform an ultrasound of the thyroid gland.
- Magnetic resonance imaging (MRI) and computed tomography (CT): These complex imaging procedures are used by doctors to treat visual disorders caused by tumors, brain aneurysms and cerebral hemorrhages (strokes), for example.
Visual disorders: Treatment
If the underlying cause is successfully treated, the visual disturbances usually disappear. Some examples:
Glaucoma patients with increased intraocular pressure also receive medication to prevent or delay further damage to the optic nerve and thus a worsening of the visual impairment. Surgical intervention is sometimes also necessary. Surgery is usually also performed for cataracts.
Vision problems: Tips – what you can do yourself
Some illnesses and injuries that cause vision problems cannot be prevented. Nevertheless, you can do a lot for the health of your eyes:
- If experience has shown that certain foods (e.g. alcohol, coffee, chocolate, cheese) can trigger a migraine attack, you should avoid these products.
- Avoid smoking because, among other things, it impairs blood flow to the optic nerve.
- Make sure you get enough physical exercise, as this improves blood circulation – which also benefits the eyes.
- Use sunglasses with adequate UV protection, as UV rays cause permanent damage to the retina and lens of the eye.
- Do not expose your eyes to draughts. It draws moisture from the eyes and can irritate them.
- Do frequent exercises such as circling your eyes or looking back and forth. This relaxes the eye muscles.
- Place your hands over your eyes from time to time (e.g. in the office) – darkness relaxes.
- Massage the area around your eyes by tapping them with two fingers. This stimulates blood circulation and tear flow.
You can prevent visual problems caused by frequent computer work with the following tips:
- Position the monitor (preferably a flat screen) at right angles to the window surface and ceiling lighting so that the distance between your eyes and the monitor is 50 to 80 centimeters.
- Provide indirect lighting to avoid eye-straining reflections or glare on the monitor.
- Regularly look up from the screen and into the distance. This trains your eyes to switch from near to far vision and vice versa.
- Take regular breaks from your PC work.
Visual disturbances: When do you need to see a doctor?
You should definitely see a doctor in the following cases:
- new onset of visual disturbances
- sudden visual disturbances such as acute deterioration of vision, sudden loss of vision or sudden double vision
- Visual disturbances in the form of flashes of light or colored rings around light sources or in the form of “soot rain”
- Visual disturbances that cannot be explained by a known visual defect (such as short-sightedness or long-sightedness).
