Dry eyes

siehe auch --->> Behandlung von erhöhtem Augendruck mit Akupunktur und chinesischer Medizin

 

Today, the clinical picture "dry eyes" is regarded as the most frequent disease in ophthalmology. Recent findings show that approximately every 5th patient examined by an ophthalmologist suffers from dry eyes. This disease has increased considerably within the last years.  This page is to inform you on dry eyes, explain the causes and therapeutic options of the disease and to give you tips what you can do to reduce your complaints in addition to the use of tear substitutes.

What is meant by the term "dry eyes "?


The tear liquid has many responsibilities. The moisture of the sensitive cornea and conjunctiva must be maintained, the cornea and conjunctiva must be supplied with oxygen and uneven spots of the corneal surface must be smoothed or leveled out. Tears contain enzymes and antibodies to resist dirty particles, bacteria and viruses getting into the tears. They flood out foreign bodies. They are regularly distributed on the ocular surface by blinking every 5 to 10 seconds.

To be able to maintain all these functions, the composition of the tear fluid is very complicated. Tears consist of three components: a mucous, an aqueous and a fatty layer. The mucous layer is located directly on the ocular surface to even out fine uneven spots on the cellular surface or the cornea and of the conjunctiva. In addition, it renderes the water-rejecting corneal surface hydrophilic, so that the subsequent aqueous layer is able to better adhere to the cornea. The aqueous layer forms the greatest part of the tear fluid. It contains proteins, enzymes and antibodies. The external layer is fatty. It is responsible for the tear liquid not to be drained off via the lid margin and not to evaporate.

The three components of the tears are produced in the large lacrimal gland located below the external portion of the eyebrows and in several smaller glands of the conjunctiva and of the lid margin.

The glandular secretion is controlled by nerve impulses and emotions. With a malfunction of this sensitive system of tear production and distribution, alleged "dry eyes" originate. Here, either the total volume of the tears is reduced or the share of single components is reduced compared to the other components.


Ophthalmology knows different terms for this disease:

    • dry eyes sicca syndrome (sicca = dry)
    • keratoconjunctivitis sicca, KCS (=dry inflammation of the cornea and conjunctiva)
    • Morbus Sjörgen (Sjörgen´s disease,named after the man who first described the disease, however, several other physical complaints are also found here,such as dry mouth and/or rheumatism).

The most appropriate term is "wetting impairment", since this term describes the functional disorder most clearly. Dry eyes very often are a chronic disease which requires constant treatment.

How do you know that you have this disease?

A variety of symptoms may indicate dry eyes.

The most frequent complaints of patients with dry eyes are:

  • dryness sensation
  • sand grain sensation
  • pressure sensation of the eyes
  • smarting adherence of the lid to the eyeball when the lids are closed
  • light sensitivity

A part of the patients also suffer from increased watering of the eyes, especially outdoors, in windy weather and also in closed rooms. In addition to the tear flow impairment, also a change in the tear film components may exist here, mostly a decrease in the fatty components, so that the aqueous component relatively predominates and, as already explained above, cannot be kept back any longer by the fatty layer and is dripping down over the lid margin.

Also in this case, the result is that a sufficient volume of liquid is no longer available for the cornea and the conjunctiva, thus leading to dry eyes.

Different from wetting impairments are allergies, where, however, the major complaints are swelling and itching of the conjunctiva. Also here, frequently a course of the complaints depending on the time of the year is typical (hay fever).

Causes of dry eyes

Dry eyes may originate due to different factors. The most common causes are:

  • decreasing tear production
  • in old age rheumatic or internal diseases,
    such as polyarthritis, diabetes, thyroid diseases Ediseases where antibodies against kendogenic substances are formed (Sjörgen´s disease, lupus erythematodes, sclerodermia)
  • skin diseases hormonic changes (menopause) neuroparalysis, e.g. after a stroke
  • consumption of certain drugs,
    such as ß-blockers, contraceptive pill,
    narcotics and tranquilizer malnutrition climatic influences (hot and dry environmental air, time of the year, air-conditioning)
  • environmental strain (ozone, dust, solvent fumes etc.)
  • monitor work
  • chronic use of vasoconstricting eye drops (alleged whiteners)


Frequently, there are several causes for dry eyes, which cannot always be determined. Therefore it is important that you inform your ophthalmologist if you are taking drugs and if so which ones, which diseases and which complaints you have in addition to dry eyes.

Consequences of the disease

First, the increase in complaints is most obvious. The foreign body sensation can increase to smarting and pain. The eyes are almost permanently red. After sleep, it is hard to open the lids. Chronic blepharitis can turn the pathological picture more severe. In addition to these subjectively disturbing complaints, the sensitive tissue layers of the ocular surface can also be damaged objectively. This is due to the fact that the hydrochloride content of the tears, which is assumed to be responsible for corneal damage, is increased in dry eyes. The consequence of an impairment of the tear film is the insufficient moisturing and drying out of the cornea and of the conjunctiva. As a result, first fine defects in the superficial corneal and conjunctival layer occur. The eye turns increasingly red, a chronic corneal and conjunctival inflammation originates.

In severe cases, the cornea may lose its transparency and turn cloudy, thus impairing the process of vision. In the worst case and without treatment this may lead to blindness.

Diagnostic options

First, your ophthalmologist will ask whether there are complaints such as dryness or foreign body sensation, smarting etc. Furthermore, you should inform him or her of all other potential complaints or diseases as well as of all drugs consumed. Then the ophthalmologist will examine your eyes with a slit lamp, where he or she can view the cornea, the conjunctiva and single areas of the anterior segment of the eye down to the lens under magnification. Here, redness of the conjunctiva and corneal opacification can already be determined. To detect smaller defects, the ophthalmologist may instill some stain, either green or red, dropwise into your eye. The stain will color small defects and exfoliated cells.
Next, the ophthalmologist will possibly determine the stability of your tear film. Again, some stain will be instilled dropwise, then you will be asked to blink several times to distribute the stain and to keep your eye open thereafter without closing the lid.

The ophthalmologist will then determine the time from the last blink to break-up of the tear film - marked through dark spots on the corneal surface - with a stopp-watch or by counting.
The longer this period is, the more stable is the tear film and the longer is the eye protected by an intact, closed surface film.
This method is called BUT determination (break-up time) or determination of the time required for the tear film to break up. The tear break-up time in healthy eyes is at least 10 seconds.
The alleged Schirmer´s test is another option for the ophthalmologist to detect dry eyes.

Therapeutic possibilities

The most important aspect in treating dry eyes is to find the reason for the wetting impairment and to treat it.
In many cases this is not possible, since the disease behind the problem itself is often not diagnosed or found and thus cannot be treated, which results in a stillstand of the disease, as is the case, for example, in rheumatism. Here, the pain is treated, however, the alterations of the joints cannot be influenced by administration of drugs.
In some cases it is not possible to remove the cause, such as administration of specific drugs which may cause dry eyes. In all these cases there is only the possibility to treat the symptoms of dry eyes by administering artificial tears to prevent a dehydration of the cornea and of the conjunctiva and to mitigate the complaints.
There is a whole series of different tear substitutes. Basically, they consist of water and a thickening agent designed to make the tear substitute adhere longer to the ocular surface and not to be flooded out so fast via the nasolacrimal duct.
In addition, preserving agents and other substances which, for example, are designed to adjust the hydrochloric content and the pH to those found in natural tears may be contained.
For very sensitive eyes or patients with allergies against preservatives, preservative-free preparations filled into alleged single-dose ophthalmic vials are available.
The efficacy and tolerance of tear substitutes are experienced very differently by the individual patients. Therefore, it is often required to try several different preparations. The choice of the right tear substitute among other things depends on the severeness of the disease. For someone who only occasionally has complaints, e.g. in air-conditioned rooms, a thin preparation will be sufficient. Patients with permanent complaints will prefer thick preparations.
Your ophthalmologist knows the different artificial tears and will discuss therapeutical changes with you if you have problems with a preparation. If your syndrome does not improve or turns worse, a second readjustment of therapy will be necessary.
Your ophthalmologist will inform you how many times you should administer the artificial tears. Usually it is left up to you to aupply drops of your drug whenever you have complaints.

Apart from very rare allergies against preserving agents, there are no side-effects accompanying artificial tears. You may thus use the preparations frequently without causing side-effects. With a consistent use of artificial tears, you can influence your disease vitally and prevent persisting defects.
In rare cases, such as lid deformation following accident or stroke, a medical treatment alone is not sufficient. Here, there is the possibility to remove the cause of the dry eye with a lid operation.
An additional alternative, which, however, is only rarely used, since it is not equally suitable for all patients, is the mechanical closure of the lacrimal point. Here, small artificial or silicone stoppers are inserted into the lacrimal point, so that the tear fluid remains at the eye because it cannot be flooded off via the nasolacrimal canal.

However, the precondition for this kind of treatment is that at least a minimum quantity of tears still exists.

Questions which are frequently asked by patients with dry eyes

I am wearing soft contact lenses. Can I use artificial tears to apply and rewet the contact lenses?


Yes, you may also use tear substitutes if you are wearing soft contact lenses. However, they should not contain any preserving agents, since they are absorbed by soft contact lenses and may damage the cornea in this way. A suitable preparation for soft contact lenses is e.g. Artelac EDO sine.

Are hard contact lenses and artificial tears compatible?


In very dry eyes, hard contact lenses should not be applied, because contact lenses need a certain quantity of tears to be able to move on the cornea when the lid is closed. A contact lens must never adhere to the cornea, since the cornea can no longer be nourished and moistened by the tears in such cases. If you occasionally feel the need to supply additional moisture, e.g. for rewetting, you can use artificial tears without hesitation. With hard lenses, preserved and non-preserved ones, such as Vidisept N or Artelac, are possible.

My eyes often water and my ophthalmologist prescribed artificial tears. Is that reasonable?


 Your ophthalmologist has chosen the absolutely right therapy for your, since you have a special form of dry eyes. The watering of the eyes is also called "paradox dacryorrhea".

In your case, the composition of the tears is changed. Even though you have a sufficient liquid portion in your tears, the outmost layer, the fatty layer, is reduced.

The fatty components create a certain surface tension, which guarantees that the tears are not drained off via the margin of the eyelid. If there are not enough fatty components, dacryorrhea and thus dry eyes originate, since there is a lack in liquid to moisture the cornea and the conjunctiva.

By administration of a tear substitute which is as thick as possible, the symptoms can be improved.


How dangerous are dry eyes?


Very severe untreated dry eyes may eventually lead to a complete corneal opacification and as a consequence to blindness.

By consequent treatment, this can be avoided in any case. You should therefore regard discomfort such as foreign body sensation or smarting as warning symptoms to remind you to supply your eye with additional artifical tears.

What else can be done to improve your complaints?

  • Make sure there is sufficient humidity in your rooms let sufficient air in
  • several times a day frequently go outside into the fresh air
  • do not direct blowers into your face when driving
  • do not consume alcohol and cigarettes
  • drink a sufficient quantity (at least 2 liters a day)
  • regular control of the visual acuity
  • regular control by an ophthalmologists


For prescription of the right eye drops, please ask your ophthalmologist.