Glaucoma

Glaucoma is a condition that leads to progressive and irreversible damage to the optic nerve.

It is the most common cause of blindness worldwide after cataracts. Because usually the patient has no symptoms except in advanced forms, it is very often diagnosed when it has already caused significant damage. It is an insidious disease that can even lead to absolute blindness, if not treated in time.
The optic nerve is the cable containing the fibers that transfer the image from the retina to the brain. When part of the fiber optic is destroyed, the part of the field of vision that these fibers correspond to is also lost. Initially, the peripheral field of vision is affected.
Glaucoma is usually due to high pressure of fluid, inside the eye. This pressure, called intraocular pressure, increases the risk of progressive destruction of the optic nerve, resulting in loss of vision.
It is a disease that has evolved for years without symptoms. Increased intraocular pressure (usually above 20-22 mmHg) is the first indication of the disease, although there are cases where we have glaucoma even with normal pressure. That’s why we all need to do our annual eye check after 40, even if we don’t have any eye symptoms, even if we see well, by measuring the intraocular pressure and checking the optic nerve.

What is the cause of glaucoma?

Glaucoma is caused by the inability to kidnap the fluid that is normally produced inside the eye. This leads to an increase in intraocular pressure. Over time, pressure on the optic nerve can lead to progressive and irreversible damage and permanent vision loss. Note that an increased intraocular pressure does not mean glaucoma if at the same time there is no damage to the optic nerve. In this case, it is called ocular hypertonia.

What are the predisposing factors for the development of glaucoma?

There are many different causes that can cause glaucoma. Most causes create an increase in pressure inside the eye at levels above the ‘strength limits’ of the optic nerve. These limits are not the same for everyone, resulting in pressure values, considered “normal” for some people, being harmful to others.
Conditions such as hypertension, diabetes, hypothyroidism may predispose to glaucoma, and patients taking cortisone for long periods in any form (pills, eye drops, even inhalations for asthma) show an increase in pressure in the eyes. Also people who had been hurt in the eye, who had inflammation and people who snore and sometimes stop in sleep to take inhalation (sleep apnea syndrome) may have glaucoma. An important predisposing factor is heredity, so people who have relatives with glaucoma should be carefully checked.

An essential element of any surgical procedure, especially cosmetic surgery, is providing the patient with sufficient time for information.

What types of glaucoma are there?

Chronic simple glaucoma
It is the most common form, and because it does not give symptoms, it is the most insidious form of glaucoma. The patient has no pain, redness or other discomfort. In this type of glaucoma the eye fluid can not drain well from the angle, which malfunctions, but remains open.

Glaucoma of normal pressure
Intraocular pressure is normal, but there is a loss of nerve fibers in the optic nerve. New technologies such as OCT can easily detect even small losses of optic nerve fibers, putting the diagnosis in time.

Acute glaucoma
In some individuals (with small-sized eyes and hyperopia) with a narrow angle and under certain conditions (such as in the dark or in the half-light) the iris can move even further forward and occlude the angle completely (angle-closure glaucoma). The symptoms are severe pain in the affected eye, blurred vision and colored circles like rainbows around the lights. Headache, nausea and/or vomiting may coexist. Acute glaucoma is an emergency condition and, if not treated immediately by a specialist ophthalmologist, can even lead to blindness within a few hours.

Glaucoma from cortisone use
The use of cortisone drugs in any form can within a few days or weeks raise the pressure of the eye due to the direct action these drugs have on the sewage system of the eye. These are mainly eye drops for chronic conjunctivitis and other eye inflammations, but also inhalations for asthma or nasal congestion or allergic rhinitis, cortisone creams for the skin, injections, etc. Intraocular pressure returns to normal levels with the discontinuation of medications, although in long-term use it can remain elevated, even for months after their discontinuation, contributing to the loss of nerve fibers of the optic nerve.

Other forms of glaucoma
Glaucoma is caused by many causes and by various mechanisms. In pseudoexfoliation syndrome and pigment dispersion syndrome particles are deposited in the corner occluding it resulting in increased intraocular pressure.
In the overmature cataract, “material” can be released from the lens and the angle clogs with a painful increase in intraocular pressure, and this is called a faclytic glaucoma. In factorial anaphylactic glaucoma the pressure increases due to an inflammatory reaction of the body against the lens. In phacomorphic glaucoma, the swelling of an overripe cataract lens pushes the iris forward by blocking the angle, while the same can happen in cases of displacement or dislocation of the lens from its position.
Various causes of ischemia, such as diabetes, carotid stenosis, etc. create new pathological vessels, which obstruct the angle, causing neovascular glaucoma.
Glaucoma can also be caused by trauma, eye tumors, surgery, etc.

Congenital glaucoma
Congenital glaucoma affects children in the first 3 years of life and occurs in 1:10000 births. The increased pressure causes swelling of the eye, with the child having a buphthalmos, because the eye looks like a “boar eye”. In addition, the child has lacrimation, photophobia, is restless, and closes or rubs his eyes. Parents should immediately rush to the ophthalmologist for a thorough examination. Lacrimation may not be due to an increase in intraocular pressure, but to a blockage of the nasolacrimal duct.

How is glaucoma diagnosed?

Dr. Nikolaos Trakos applies the most modern methods of diagnosis of glaucoma at the Ophthalmology Center EYLID he created, with the aim of better quality services. These are the CT of the optic nerve, control of the visual fields, corneal pachymetry, gonioscopy, anterior chamber OCT, measurement of intraocular pressure, and fundoscopy by photographing the optic nerve.
With these 7 testing techniques that are done on a visit to the EYD-LID Ophthalmology Center, the data are collected and the diagnosis is made through sophisticated algorithms.
In some cases, it may be necessary to measure intraocular pressure throughout the day, and be performed on each eye separately, and often at different times of the same day, to record its 24-hour variation (tonometric curve). Usually the intraocular pressure is higher in the early hours and then decreases to return the next morning. This is why most anti-glaucoma eye drops are administered in the evening, so as to prevent morning increase.
22 mmHg is considered to be the upper limit of normal for intraocular pressure. The blood pressure alone is not enough to make a diagnosis, and all clinical and laboratory data should be taken into account to decide whether the patient needs treatment or not. In addition, as already mentioned, values “within normal limits” are not necessarily safe and do not exclude the possibility of damage to the optic nerve. The measured pressure needs to be corrected based on the thickness of the central area of the cornea, in order to calculate the actual intraocular pressure. Corneas with a thicker than what is considered a mean value in the general population (545 µm) overestimate intraocular pressure (the actual pressure is proportionally less), while thinners underestimate it (the actual pressure is proportionally greater).

Central corneal thickness	490	505	515	530	545	560	575	585	600
Correction in mmHg	+4	+3	+2	+1	0	-1	-2	-3	-4

Central corneal thickness

Correction in mmHg

490

505

515

530

545

560

-1

575

-2

585

-3

600

-4

Gonioscopy is the direct control of the angle (the drainage of the eye) by the ophthalmologist using a special lens. With this examination, the range of angle as well as any pathological findings that may obstruct it can be unequivocally determined.
There are several calibration systems for angle amplitude, but the term narrow angle is generally used to describe the small distance between the iris and the inner surface of the cornea that anatomically limits the outlet of the aqueous humor and can lead to an increase in pressure. Evolution of this examination in the most modern imaging way is the OCT anterior chamber, done by Dr. Nikolaos Trakos, by which the angle is measured in a precise way.

Why choose Dr. Trakos?

Dr. Trakos’ contribution to the field of anterior segment and cataract surgery, as well as to the treatment of vision problems, has changed the lives of many people by improving their sight and quality of life.

What is the treatment of glaucoma?

The goal of treatment is to reduce intraocular pressure. The treatment varies depending on the type of glaucoma and is individually tailored to each patient. In the early stages, topical medication with drops that are instilled by the patient is sufficient. Other patients need a combination of eye drops.
The medication is carefully selected based on the patient’s systemic health profile and the condition of the ocular surface in relation to the pre-existing Dry Eye Syndrome. So many times drops are selected without preservatives.

The patient at the EYE-LID Ophthalmology Center is trained to correctly drop the drops. In some other cases, Laser surgery is required which may help to further reduce intraocular pressure.
Cataract removal also has an important place in reducing eye pressure and controlling glaucoma.
Finally, in advanced stages or in rapid progression, where conservative treatment can not control the progressive damage of the optic nerve, the surgical intervention has its place. The range of surgical procedures for glaucoma is very wide. The term MIGS (Minimally Invasive Glaucoma Surgery) includes a series of microinvasive methods (e.g. stent placement) in the anterior chamber of the eye that lead to a significant reduction in intraocular pressure. Trabeculectomy surgery is the conventional method that requires intensive postoperative follow-up, but is the most effective method in long-term disease control.
Dr. Nikolaos Trakos applies the most modern techniques of glaucoma diagnosis and treatment. An important role is played by the administration of neuroprotective agents such as citicoline, the latest development in the field of glaucoma.
But at a microinvasive level the most important development is the SLT (Selective Laser Trabeculoplasty). This Laser regulates the glaucoma of patients and does not need to drop drops. This technique is applied with one of the most modern Lasers available at the Eye-Lid Ophthalmology Center.