Visual disturbances
The term visual disturbance refers to pathological changes in optical perception. These include reduced visual acuity, restricted field of vision, eye twitching, and ‘double vision’.
There are numerous triggers of these kinds of visual disturbance such as eye diseases, neurological disorders or tumours.
Symptoms
But what are the symptoms of a visual disturbance?
- ‘Double vision’ (known as diplopia) can be caused, for example, by excessive alcohol consumption, by disorders of certain cranial nerves or in connection with multiple sclerosis.
- Seeing lightning flashes or even the feeling of seeing through a curtain usually occurs in conjunction with detachment of the retina.
- If, for example, you feel you have a veil in front of your eyes or you see everything around you as blurred, these symptoms may be due to glaucoma , weak eyesight, excessive strain on the eyes or retinal detachment.
- Certain 'disruptive elements’ such as a ‘shower’ of floaters or ‘flying mosquitoes’ (known by the medical term ‘mouches volantes’) in front of the eyes may indicate conditions such as retinal detachment or vitreous detachment.
- Visual field defects (commonly known as ‘tunnel vision’) may also be caused by glaucoma or tumours.
- Disorders of colour vision can either be congenital (as in the case of red-green colour blindness) or acquired (e.g. as a result of a glaucoma attack – a sudden increase in intraocular pressure caused by an impaired flow of the aqueous humour – or poisoning by digitalis, a strong heart remedy derived from the leaves of the digitalis (foxglove)).
Causes
There are many causes of visual disturbances. However, a distinction must be made between more harmless and more severe, more serious causes. The key causes of visual disturbances include:
- Short-sightedness (myopia)
- Far-sightedness (hyperopia, hypermetropia)
- Age-related far-sightedness (presbyopia)
- Squint (strabismus)
- Astigmatism, also known as corneal irregularity
- Age-related macular degeneration (abbreviated as AMD)
- Glaucoma
- Cataract
- Vitreous opacity
- Vitreous detachment
- Vitreous haemorrhage
- Retinal tear/retinal detachment
- Inflammation of the vascular layer (uveitis)
- Inflammation of the optic nerve
- Stress-related visual disturbances
- Multiple sclerosis (MS)
- Graves’ disease
- Migraine
- Inflamed arteries
- Vascular occlusion in the retina
- TIA (transient ischaemic attack)
- Widening of a cerebral artery (brain aneurysm)
- Bleeding in the area of the brain
- Brain or eye tumour
- Pathological muscle weakness
- Consumption of alcohol, tobacco or illegal drugs
- Side effects of other medicines
Diagnosis
Visual disturbances are diagnosed by an ophthalmologist. He or she will first of all ask you about your medical history in detail (case history). He or she will then ask you a wide range of questions to find out when the visual disturbances occur, how they manifest themselves (e.g. through eye twitching or double vision) and whether you have any other complaints (e.g. eye pain, headaches, nausea). The ophthalmologist will then carry out various examinations to uncover the cause of your visual disturbance and then be able to treat it accordingly:
- Ophthalmological examination: In the case of eye problems such as impaired vision, an eye examination by an ophthalmologist is a routine course of action. Among other things, the ophthalmologist will check vision and can therefore identify a refractive error in the eyes as the cause of the visual disturbances, for example.
- The slit lamp examination: Using an ophthalmological instrument – the slit lamp – the ophthalmologist can examine the anterior (front) segment of the eye to diagnose cataracts or inflammation of the middle layer of the eye (known as uveitis).
- Ophthalmoscopy: The back of the eye is examined with the aid of an ophthalmoscopy. This is important, for example, if the reason for the visual disturbance is a retinal disease or an eye tumour.
- Measurement of intraocular pressure (tonometry): It is mainly performed when glaucoma is suspected as being the cause of the visual disturbance.
- Blood tests: If an infectious inflammation of the optic nerve or Graves’ disease is suspected, a blood test often provides the information needed.
- Neurological investigations: If certain neurological disorders or diseases (e.g. multiple sclerosis, inflammation of the optic nerve) could explain the visual disturbances, the condition and function of the nerve pathways must be checked.
- Ultrasound examination (medical term: sonography): An eye ultrasound scan is necessary to diagnose retinal detachment, eye tumours or optic nerve changes.
- X-ray examination of the blood vessels (known as angiography): Vessels in the retina and in some cases in the choroid can be made visible and examined on X-ray images by injecting dyes. This vascular X-ray is particularly important if there is a suspicion of age-related macular degeneration (AMD).
- Magnetic resonance imaging (MRI) and computed tomography (CT): These complex imaging techniques are used, for example, for visual disturbances caused by tumours, brain aneurysms, and cerebral haemorrhages.
Treatments
If the underlying cause(s) of a visual disturbance are successfully treated, these conditions can usually be successfully remedied.
For example, visual disturbances resulting from short and far-sightedness can be corrected using glasses or contact lenses, sometimes also with the help of surgical procedures.
If, on the other hand, inflammation is responsible for your visual disturbances, then the appropriate medication will usually help to alleviate the relevant inflammation effectively and permanently.
If you suffer from increased intraocular pressure (i.e. glaucoma), your ophthalmologist will first prescribe medication for you to prevent or delay further damage to the optic nerve and therefore the increasing severity of the visual disturbances. Sometimes, however, a surgical procedure is required.
And in the case of a cataract, surgery is usually also carried out.
Aftercare
It is important that you regularly have all the necessary check-ups carried out by your ophthalmologist. This is the only way to ensure that your eyes are properly healthy.
The frequency and duration of the check-ups, or the time interval between the individual examinations, depend, of course, on the condition that is causing your visual disturbance, and also on its severity.
It is therefore essential that you coordinate your further, individual treatment plan with the ophthalmologist treating you.
FAQs
Which foods are good for the eyes?
Foods that are good for your eyes include peppers, carrots, beetroot, broccoli, citrus fruits and green vegetables such as lamb’s lettuce, spinach, peas and kale. Overall, a balanced diet is the determining factor for your health.
Why is it sensible to wear sunglasses?
UV rays cause lasting damage to the retina and the eye lens, which is why wearing sunglasses with sufficient UV protection is an absolute must in excessive sunlight.
How can I prevent vision problems when working frequently with a computer screen?
- Position the monitor (preferably a flat screen) at a right angle to the window surface and the ceiling lighting – the distance between the eye and the monitor should be 50 to 80 centimetres
- Provide indirect illumination to prevent reflections or glare on the monitor that may strain the eyes
- Regularly looking up and out into the distance – i.e. away from the screen – is a good exercise for training the eyes’ ability to switch from near to far (and vice versa)
- A deliberate frequent blink keeps the surface of the eye moist
- Regular breaks from work on the screen are essential to protect the eyes from a visual disturbance for as long as possible
