Glaucoma usually takes years to develop and does not give any signals. Sometimes 30 years pass and suddenly it turns out that the disease has almost completely destroyed the optic nerve. The patient's eyesight is irreversibly lost. And you don't need much to keep your eyesight despite your illness.
Why is glaucoma diagnosed so late and can it be otherwise? What are the chances of a sick person to maintain their eyesight? We talk toprof. Marek Rękas , head of the Ophthalmology Clinic of the Military Medical Institute in Warsaw, as well as a national consultant for ophthalmology.
What exactly is glaucoma?
Prof. Marek Rękas : This is a group of diseases characterized by a progressive atrophy of the optic nerve, which gradually leads to loss of vision. There are two primary types of glaucoma - open angle and closed angle glaucoma. If the angle is closing, the outflow of the aqueous humor may suddenly become blocked. The pressure in the eye rises sharply, there is severe pain in the head and eye, vision hazy, even nausea. This speeds up the diagnosis if, of course, the patient goes to an ophthalmologist or the emergency room. This applies to 20% of patients, in the remaining 80% of cases the angle is open, but the progressive lesions in it make it difficult for the aqueous humor to escape. The pressure in the eye rises slowly - we often notice the effects only after many years, when the optic nerve is almost completely destroyed.
Can you have advanced glaucoma and not know it?
M.R.:Let's start with the question: what do we call seeing? First of all, we distinguish central vision - we see objects, colors, letters. But we also have peripheral and peripheral vision, which is ensured, among others, by orientation in space. This is what glaucoma takes first. People think they can see well, because they can read etc. Defects in the peripheral vision may not be noticed for years, or they do not associate certain events with progressive blindness. This applies, for example, to seniors who stumble over something more and more often. In the first place, glaucoma takes away the primary, "unconscious" vision of details on the periphery, not registered by the central vision, but for example warning of danger.
What are the risk factors for glaucoma?
M.R.:First, glaucoma oftenit runs in families, i.e. it may have a genetic condition. Race is important (in Asians, the closing angle is more common) and myopia (for anatomically weaker eyes). Age, cardiovascular disorders and many other he alth problems also play a role. But the current view is that the causes of glaucoma lie in the structure of the sclera and other eye structures.
Disease progresses as untreated high pressure destroys optic nerve?
M.R.:Yes. Therefore, one treatment option is to administer drops that reduce the production of aqueous humor. When there is less of it, the pressure in the eye drops. But this type of conservative therapy also has side effects, such as weaker nourishment of the eye structures. This is one of the reasons why patients with glaucoma are more likely to develop cataracts. Moreover, the drops are not effective in regulating intraocular pressure throughout the day in all cases. And one more thing - they work on the surface of the eye and with prolonged use of them, chronic inflammation of the eye often develops, which in the future may affect the effectiveness of the surgery.
So there are also other methods of lowering eye pressure …
M.R.:That's it. The second direction of treatment is to increase the outflow of aqueous humor and thus equalize the intraocular pressure. For this purpose, lasers or operations are used. The current tendency is to introduce them as soon as possible - even before drug treatment.
Proper prophylaxis, i.e. regular visual field tests and eye pressure tests, as well as more and more perfect therapies, allow to slow down the development of glaucoma enough to maintain vision for the rest of a long life.
What determines the choice of therapy?
M.R.:First of all, its effectiveness and safety. In the case of glaucoma, unfortunately, high efficiency often goes hand in hand with an increased risk of complications. Remember that the goal of glaucoma treatment is to keep your vision as long as possible and of the best possible quality. The essence of this disease is that it progresses and the changes are irreversible. Therefore, untreated glaucoma deprives vision completely over time.
What treatments are used in Poland?
M.R.:Same as in the world. The safer ones include, for example, sclerectomy, which, in simplified terms, consists in exposing the outer wall of the Schlemm's canal, which improves the outflow of aqueous humor. Trabectuloctomy is the preparation of an opening in the eye through which the aqueous fluid is drained under the conjunctiva. Canaloplasty involves inserting a drain into the Schlemm's canal through which a special substance is introducedincreasing its volume. We were the first in Poland to perform it in our clinic. It is a procedure comparable to trabectuloctomy, but with a much higher degree of safety. A novelty are micro-invasive procedures - e.g. insertion of a stent into the Schlemm's canal (as in cardiology, only in the microscopic version), extending the place of the outflow of aqueous humor.
In the world, 60 million people suffer from glaucoma, of which 7 million are blind. Accelerated aging of the optic nerve as a result of this disease is an epidemic of the 21st century.
What awaits us in the future?
M.R.:The future is in controlling the pressure inside the eyeball with the help of electronic sensors, e.g. placed in intraocular lenses. It takes place, for example, every three minutes. Such a measurement is invaluable for an ophthalmologist. The increase in eye pressure is the only confirmed risk factor for glaucoma, which is why monitoring it is so important. Even incidental pressure surges (e.g. when the eyelids rub or compress) in the eyeball can initiate degenerative changes in the optic nerve. Telediagnosis is also the future, for example, examining the field of view at home in front of a computer and sending the collected material for analysis by electronic means, without leaving your home.
How to wisely conduct prophylaxis?
M.R.:You need a system as developed by AMD (Macular Degeneration). The Americans provide a good example. 2% of the population are treated, i.e. diagnosed, but as much as 10% are covered by screening (a program of regular checkups). This often applies to entire families due to a genetic factor. The point is to show the progression of changes in the visual field, i.e. accelerated aging of the optic nerve. This is a prerequisite to start treatment early enough.
What should a visit to an ophthalmologist look like?During one visit, the ophthalmologist should check not only visual acuity. He must examine the anterior segment of the eye, examine the fundus, assess the condition of the retina and optic nerve, measure the pressure in the eyeball. These are studies that allow to determine the degree of risk, among others glaucoma, cataracts or AMD.
If you suspect glaucoma, you must additionally perform a visual field examination. The most important thing is monitoring, i.e. regular check-ups: measuring the pressure in the eye every 2-3 months and examining the visual field every six months if glaucoma is suspected.
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