symptoms

Intraocular pressure - normal values, symptoms and causes

Intraocular pressure - normal values, symptoms and causes / symptoms

Increased and too low intraocular pressure

The right pressure conditions in the eye are essential for trouble-free vision. It can be all the more dangerous if the intraocular pressure (Tensio) is impaired by health problems. Behind this are usually pathological changes of the eye, which hinder the correct outflow of the eye's aqueous humor.


contents

  • Increased and too low intraocular pressure
  • definition
  • Causes of increased intraocular pressure
  • Causes of low intraocular pressure
  • diagnosis
  • Treatment for changes in intraocular pressure
  • Naturopathy
  • Self-help and home remedies with increased intraocular pressure

definition

The internal pressure in the eye (Oculus) is crucial for many factors that affect ocular function as well as its anatomy. For example, the intraocular pressure ensures a constant distance between

  • cornea (Cornea)
  • eye lens (Phakos)
  • and retina (Retina),

which on the one hand ensures optimal ventilation of the epidermal layers of the skin and on the other hand also prevents these layers from interfering with one another in their visual function by sticking together.

Among other things, the intraocular pressure ensures that the eyeball retains its round shape. (Image: sakurra / fotolia.com)

The function of these skin layers is also influenced by the intraocular pressure. For example, it ensures an accurate alignment of the photoreceptor cells (Facet receptors), which are located in the retina and are responsible in the eye for the absorption of light. Without adequate pressure conditions in the eye, people have problems with the light-dark-vision.

In addition, the intraocular pressure is also responsible for an adequate curvature of the inner wall of the eye, which is necessary to ensure perfect vision and also to be able to perceive visual impressions on the left and right of the central field of vision.

The natural intraocular pressure is between 10 and 21 mmHg. This comes through the so-called aqueous humor (Humor aquosus). As the name suggests, she is in the eye fluid chamber of the eye (Camerae bulbi), which can be divided into a front and a rear chamber of the eye. The anterior chamber of the eye forms the hollow vault of the eye directly behind the cornea, while the posterior chamber of the eye around the lens between the Iris (Iris) and the vitreous (corpus vitreum) located in the skull.

The aqueous humor is formed in the ciliary (Corpus ciliare). They are located laterally behind the pupil and produce the ocular fluid of components which, with the exception of the red blood pigment, are very similar to those of the blood serum and consist essentially of the following:

  • water
  • amino acids
  • antibody
  • ascorbic acid
  • electrolytes
  • lactic acid
  • proteins

Every day, between 3 and 9 ml of aqueous humor is produced in the ciliary bodies, which, after it has formed, first pours into the eye chamber, regulating the intraocular pressure and adequately moisturizing the eye. Then the eye fluid flows over the chamber angle (Angulus iridocornealis) in the Schlemm's canal (Venous plexus) again. Named after the German physician and anatomist Friedrich Schlemm, this channel transfers the aqueous humor back into the bloodstream via a fine network of eye veins.

If the pressure in the eye is elevated or too low, it is important that treatment be taken as soon as possible to avoid irreparable eye damage. (Image: YakobchukOlena / fotolia.com)

And this is exactly where the most common cause of increased intraocular pressure lies. For if the aqueous humor can no longer flow away completely, for example due to obstruction of the chamber angle or Schlemm's canal, the pressure in the eye chambers increases.

Likewise, it may come to a low intraocular pressure when the aqueous humor drains too fast. In both cases, the patient's vision is at great risk. Also, irreparable eye damage can threaten, which is why a timely treatment of a disturbed intraocular pressure is very important.

Causes of increased intraocular pressure

As already indicated, the intraocular pressure is due to the amount of aqueous humor, which is located in the front of the eye in the eye chamber. Consistent intraocular pressure is therefore essential for vision, since only then all eye structures involved in vision can perform their tasks adequately. On the other hand, if too much pressure prevails inside the eye, the functionality of the fine and sensitive eye elements is enormously impaired. Corresponding pressure increases usually result from one of two influencing factors:

  • Either because of a pathological change in the eye, more aqueous humor is produced than can drain away,
  • or because of a pathological change in the eye, less aqueous humor is removed than is produced.

In both cases, the imbalance of increased production and / or decreased drainage results in increased levels IOD (intraocular pressure), how the intraocular pressure is called in professional circles.

As a cause for example constrictions (Stenosis) in the chamber angle, or in the Schlemm Canal in question. This may be the case, for example, due to vascular changes or malformation. Other diseases that can not be ruled out as the cause of increased eye pressure due to impaired aqueous humor drainage are cysts, tumors and inflammations in the area of ​​the chamber angle.

In addition, injury trauma to the eye, foreign bodies, adhesions in the eye tissue (e.g., by surgical scars) as well as a long-standing diabetes illness to be able to narrow the vessels of the drainage system in the eye so that accumulates more aqueous humor and so the intraocular pressure rises.

Often underestimated as a cause of elevated intraocular pressure, sometimes stress and drugs. Stress influences do not only arise for the eye from hectic everyday situations. Likewise, environmental pollutants, the continuing quake of heavy loads (due to increased pressure load) and diseases such as high blood pressure increase the stress burden of the eye.

Increased blood pressure can also affect intraocular pressure. (Image: stokkete / fotolia.com)

In the field of drug substances, numerous drugs can also increase the IOP as a side effect. Very often this happens, for example, in the treatment with cortisone. For this reason, it is recommended to have the eyes checked by a doctor before and during extended cortisone therapy.

Medicines used to treat cancer are also known to increase intraocular pressure. In addition, decongestant nasal sprays are currently at least suspected of provoking increased pressure levels.

Attention: In all these cases can from the permanently elevated intraocular pressure untreated a so-called glaucoma arise. Better known as "the green star" hides behind this disease irreparable damage to the optic nerve. The risk of developing glaucoma is not exactly low. In Germany alone, about 5 million people have an increased risk of glaucoma and about 800,000 people have glaucoma. In fact, this disease is quite often preceded by an elevated intraocular pressure.

Causes of low intraocular pressure

Also, too low intraocular pressure, which is due to insufficient aqueous humor in the eye chamber, can lead to serious health consequences for the eyesight of the eye. The underlying mechanism is the exact opposite of the mechanism of elevated intraocular pressure. This means a reduced pressure in the eye

  • either by a reduced production of aqueous humor,
  • or by increased drainage of aqueous humor arises.

Among other things, a reduced production of aqueous humor may occur due to a pathological change in the ciliary body. Again, there are stenoses in the area of ​​the corpus ciliare, (for example due to cysts, injuries or inflammations) to name as conceivable causes.

An excessive outflow of aqueous humor, on the other hand, can also occur unintentionally after interventions on the eye, for example in glaucoma patients. In this case, an operation to improve the outflow of ocular fluid leads to an unwanted lowering of intraocular pressure beyond the desired standard.

Warning: Prolonged or prolonged reduction of the IOP may result in detachment of the retina from the underlying choroid. In the worst case, this retinal detachment provokes complete vision loss and blindness!

diagnosis

Changes in intraocular pressure are often creeping processes, the consequences of which become noticeable only very late in the advanced stage of the disease. Since however the green star manifests itself predominantly from the second half of life and disturbances in the outflow or the production of aqueous humor are often due to age-related remodeling processes of the eye, it is recommended that from the age of 40 about every one to two years Eyes for vision and intraocular pressure should be checked as a precaution.

Important: It should be noted, however, that these are not examinations, the costs of which are generally borne by the health insurance funds, but so-called individual health services (iGeL), which must be self-financed or only subsidized. Only with an existing increased risk profile or the follow-up of existing illnesses, the benefits will be covered by the health insurance.

A primary suspected diagnosis of falling within the normal range intraocular pressure, the family doctor often alone because of the presence of characteristic symptoms and risk factors. As soon as they come up in a medical history and a suspicion hardens, GPs usually refer the person to a local ophthalmologist or ophthalmic hospital (concerning the eye) Department. Here are the appropriate equipment for the diagnosis of eye diseases available and can reliably detect even the smallest inconsistencies.

Regardless of which way the patient comes to the ophthalmologist, the diagnosis of intraocular pressure changes involves several steps. Which includes:

  • Measurement of intraocular pressure (Tonometry)
  • ophthalmoscopy (Ophthalmoscopy)
  • Testing of eyesight (Visual Acuity Test)

Measurement of intraocular pressure

For the measurement of the IOD the ophthalmologist has several measuring methods available. In healthy people, the standard is between 10 and 21 mmHG, whereby the age, body constitution, blood pressure, pulse and even the time of day can generate a wide range of variation, which must be considered by the examining physician. To measure as accurately as possible, therefore, there are different approaches that are constantly evolving:

1. Goldmann applanation tonometry: In Goldmann applanation tonometry, the ophthalmologist presses the previously anesthetized cornea of ​​the eye for a short time with a 3 mm wide pressure sensor to a certain depth. The more force needed to flatten the cornea at the desired depth (to applaud), the higher is the existing intraocular pressure.

2. Non-contact Tanometry: A slightly newer method does not involve direct contact with the cornea and is therefore also called non-contact tonometry. Here, a device blows a jet of air at the cornea of ​​the opened eye and determined from the measured time, which requires the air pulse to flatten the cornea at a certain depth, the pressure prevailing inside the eye.

3. Measurement with contact lens microsensor: The research is very intensively concerned with the development of better measuring techniques. Among other things, contact lenses with microsensors are currently being developed, which should be able to measure the IOD continuously over a longer period of time.

During the ophthalmoscopy, the doctor looks into the eye from outside through an ophthalmoscope. (Image: Henrik Dolle / fotolia.com)

ophthalmoscopy

During ophthalmoscopy, the ophthalmologist uses an ophthalmoscope to examine the normal outside of the eye. Here he can check several structures for pathological changes. For example, the light incidence of the ophthalmoscope allows the optic nerve head located in the background of the eye and the yellow spot to be inspected more accurately. And also fine tissue layers such as the retina and the choroid, together with their fine blood vessels for the care of the eye are visible thanks to the ophthalmoscope.

With the help of this approach, the ophthalmologist can assess whether damage to the optic nerve has already occurred as a result of a pathological change in the IOP (with increased intraocular pressure) or on the retina (at low intraocular pressure) have set and control their course exactly.

The examination method itself is painless, but it must be remembered that the eye is previously treated with atropine drops, which cause a dilation of the pupil for better viewing of the fundus. Because of their effect, the eye drops are also called "wide drops. This process affects eyesight for several hours and therefore the person concerned may not operate machinery, or use a vehicle or bicycle on the day of the examination. It is therefore common practice to free yourself for the day of the examination.

Testing of eyesight

Although the performance of eye tests during the diagnosis in no direct relation to the intraocular pressure, but can be assessed so that whether pathological changes in the eye have already led to impairment of vision or if in addition there are other visual impairments. In order to perform the test, the ophthalmologist has various measuring and comparative methods that can be used to assess and assess visual acuity as well as contrast, color and 3D vision.

Danger: In contrast to the routine check-up, or to diagnose existing risk factors, an acute glaucoma case is always an emergency situation, an immediate ophthalmological examination and treatment needs!

Treatment for changes in intraocular pressure

Which treatment measures are necessary to remedy the internal pressure changes in the eye, must be decided on a case-by-case basis individually by the responsible ophthalmologist. Usually, however, is usually a drug therapy underlying diseases. There are also some herbs and home remedies that provide help with increased or decreased intraocular pressure. Nevertheless, eye surgery can never be completely ruled out if the procedure is unfavorable.

Medication

The drug therapy consists in changed intraocular pressure primarily from a combination therapy of different eye drops with different drugs and therapeutic approaches. Eye drops containing prostaglandins as an active ingredient are useful, for example, to improve the outflow of aqueous humor. Beta-blocker eye drops are again used to reduce aqueous humor production.

On the other hand, eye drops that contain carbonic anhydrase inhibitors are suitable for regulating aqueous humor production by promoting blood circulation. A mere regulation of aqueous humor production without a circulation-promoting background can be achieved with alpha-agonists as an eye-dropping agent.

Which eye drops are to be used in which combination, the doctor decides depending on the underlying cause and progress of the disease process. It should be noted, however, that eye drop therapy for abnormally altered intraocular pressure often takes a lifetime, unless surgical therapy is considered.

Eye drops usually accompany patients with pathologically changed intraocular pressure for a lifetime. (Image: Stefano Garau / fotolia.com)

Operative therapy

If a retinal detachment is due to a too low IOP or threatens to develop, can be achieved using various surgical and laser techniques, an adhesion of the detached retina with the underlying choroid. If the drug therapy is exhausted with elevated IOP, often only the way remains over operative measures, in order to avoid a blindness by the arising glaucoma. The surgical approaches depend entirely on the causative mechanism.

If the cause lies in an overproduction of aqueous humor in the ciliary body, it can be treated by means of cyclophotocoagulation. The term describes a special laser technique that ensures that the parts of the ciliary body stop working and consequently less aqueous humor is produced.

If a drainage dysfunction is the cause of the altered intraocular pressure, it can be treated with surgical methods such as viscocanalostomy or a drainage implant. In both cases, the operation aims at an additionally introduced drainage device.

Naturopathy

Pathological changes in intraocular pressure can rarely be completely treated by the medicinal plant and homeopathic approach alone. However, the person concerned has some resources at his disposal which support the metabolic processes in the eye and thus also serve conventional medical therapeutic measures.

For example, in homeopathy, the use of the common cowbell has (Pulsatilla Vulgaris), Eyebright and the Bach flower Rock Rose, Rock Water and Walnut so far brought good results. Also, teas or mother tinctures with the components of the horse chestnut are considered to be good helpful hasumittel to reduce intraocular pressure, as are pansies and violets supportively used successfully for the therapeutic reduction of IOP.

Self-help and home remedies with increased intraocular pressure

Since stress at elevated intraocular pressure is discussed not only as a facilitator, but even as a triggering factor, high-risk patients can also help themselves to keep their IOD within the normal range by avoiding stress or to bring it back into the normal range.

Regular and adequate sleep is especially important for your eyes to recover during this time. (Image: F8studio / fotolia.com)

Important here is learning and applying a stress-reducing everyday behavior. This can, for example, consist of the correct planning of the daily routine with sufficient rest periods and a regular sleep rhythm. The latter is especially important because the eyes can rest intensely while sleeping. Targeted relaxation training, such as yoga, meditation or progressive muscle relaxation, can help with stress relief.

Another important point in the private support of the therapy is a balanced diet. Above all, a diet rich in magnesium, carotene and vitamins is unlikely to be important here, since these nutrients particularly enhance ocular function. This is especially true of magnesium, which is found abundantly in cereals and legumes such as peas, beans, corn, sesame, linseed, amaranth, quinoa, sunflower and pumpkin seeds and bananas. Furthermore, the enjoyment of green tea should promote blood circulation in the eyes.

Adjust or at least reduce patients with unhealthy (especially too high) Eye pressure, however, coffee and other caffeinated foods. Because caffeine raises blood pressure, which in the case of excessive IOP can aggravate the symptoms. (Ma)