El glaucoma it is one of the eye diseases that still today presents serious problems, especially because it ultimately leads to blindness. Currently, it is estimated to be the second leading cause of blindness in the Western world.
What is glaucoma and what are its consequences?
El glaucoma defined as a disease in which there is a optic nerve damage, generally due to ischemic cause (lack of blood supply), and which manifests itself with irreversible loss of vision. We know that it has a hereditary pattern, with a genetic basis and that it usually manifests after the age of 40 (its most common form, open angle).
We also know that it is related to many general diseases, such as high blood pressure and low blood pressure, diabetes, circulatory disorders, immune diseases and much more. As if this were not enough, there is also a ampThe number of drugs that can induce or decompensate glaucoma, especially anxiolytic and antidepressant drugs.
In most cases there is a decrease in the output of the liquid that circulates inside the eye (aqueous humor), accumulates inside and causes a increased eye pressure (Figure 1). The increased pressure compresses the blood vessels supplying the retina and, very especially to the Optic Nerve in its intraocular portion (Papilla).
This effect is accompanied by a deficit in the supply of oxygen, ischemia and cell death. The consequence of this process is the interruption in the electrical signal that goes from the eye to the brain, where the visual sensation is generated; it is as if "the cable of the current that goes from the plug to the lamp is peeled, although there is electricity and the bulb is good, there will be no light.
In the case of glaucoma, vision loss occurs, irreversibly, since the damaged Optic Nerve never recovers, it is an extension of the brain and its neurons do not have regenerative capacity.
How glaucoma manifests
In most cases, the increase in Intraocular pressure it does not produce apparent discomfort, the patient does not notice anything, that is why we say that it is a “silent disease”, “treacherous”, because it does not warn. The ischemia that occurs in the NO will injure the internal tissues until vision loss begins, first in the peripheral area of the campor visual, reduction of contrasts, alteration of colors and finally loss of central vision.
Only in the acute forms of angle-closure glaucoma, there is intense pain that prompts the patient to go to the ophthalmologist, although it only represents 1% of cases.
What can we do to prevent glaucoma
The most important thing is to carry out regular check-ups by the ophthalmologist. As it is, in most cases, an increase in intraocular pressure, the simple measurement of this pressure helps us to reveal a possible glaucoma at the beginning.
There are also some risk factors that need to be considered, in order to establish screenings more rigorously: age over 50, Caucasian or African-American race, vascular disorders, and a family history of glaucoma.
How glaucoma is treated
In most cases, the glaucoma treatment It is aimed at reducing intraocular pressure. As the cause is usually a deficit in the evacuation of intraocular fluid (aqueous humor), the first action is to partially "close" the faucet that synthesizes aqueous humor.
For this we use eye drops that have a high degree of efficacy although they are not exempt from side effects, some produce alterations in the heart or at the respiratory level (Beta blockers). For this reason, it is necessary to carry out, in addition to a strict ophthalmological control, a systemic study by the internist.
to open an orifice and restore the outflow of aqueous humor.
When eye drops are insufficient to control the disease or there is a contraindication to use, we resort to measures aimed at improving the outflow of aqueous humor, basically we can make a glaucoma laser treatment (Figure 2), or filtering surgery (Figure 3). Laser has not been shown to be definitive in the long term, which is why it is usually recommended glaucoma surgery.
performs a "filter" that improves the outflow of aqueous humor, without the need to penetrate inside the eye.
What are the news around glaucoma
In recent years we have learned more about glaucoma and there have also been technological advances that help us diagnose, prevent and treat this disease. Perhaps the most significant is the fact that the simple taking of intraocular pressure, although it is a first diagnostic factor, is not enough to reveal an incipient glaucoma.
Today we know that the 30% of glaucomas occur without elevation of pressure and that the methods we used to measure this pressure are not as accurate as they should be since there are anatomical and biomechanical factors that induce errors in the values obtained.
For an accurate diagnosis we must resort to the combination of several tests: pressure taking with non-contact systems and with individual adjustment of corneal biomechanics (corneal hysteresis),campSensitivity threshold imetry, especially with dual-frequency stimuli, and analysis of the Optic Nerve head and nerve fibers using polarimetry. With these three tests we can make an early diagnosis of the disease and establish a very precise follow-up to see if the prescribed treatment is effective.
Another of the great advances refers to the treatment of the disease, we have new eye drops with very effective active ingredients to reduce intraocular pressure and not cause collateral damage, are the derivatives of prostaglandins.
When surgical treatment is required, things have also improved, we have gone on to use less invasive techniques, it is no longer necessary to enter "inside the eye", we can make a valved filtration system with the procedures we call: "Deep non-perforating sclerotomy" "(Figure 3). These techniques are very effective and much safer. The complication rate has been drastically reduced and patients' recovery is much faster.
What the Advanced Ophthalmology Area contributes
In our Ophthalmology Department we have always been very sensitive to this disease and we have created the Glaucoma Unit equipped with specialists in this disease with a ampHe has experience in diagnosis and treatment, both medical and surgical.
This Unit is equipped with new non-contact intraocular pressure measurement systems and corneal biomechanics adjustment (ORA), campcomputerized imetry, topography of papilla (OCT), polarimetric study of retinal fibers (GDx) and ultrasound high resolution for study anterior segment (UBM).
In surgery we bet on non-perforating techniques that in recent years have become the techniques of choice. Our Department of Ophthalmology was one of the pioneers in introducing this surgery in Spain, with new contributions that have improved results.
To conclude this review on glaucoma, I would like to insist on the importance of prevention, since it is a disease that does not warn and the final consequence is blindness, so it is necessary to go to the ophthalmologist periodically, especially in the patients with risk factors. I would recommend that the revisions be made in Centers where they have glaucoma specialists and where they can prove that they have the new technologies for a better diagnosis and treatment of the disease.
