Glaucoma

Our eyes are our unique windows that allow us to perceive the world and witness all the beauties of life. However, this unique system can sometimes be threatened by diseases that progress silently and deeply without any symptoms. Described in the medical world as the "silent thief" of sight, Glaucoma (Eye Pressure) is one of the most dangerous eye diseases that can lead to permanent and irreversible blindness if not diagnosed early.

What is Glaucoma (Eye Pressure)?

To maintain the vitality and spherical shape of the eyeball and to nourish avascular tissues like the cornea and lens, a special fluid called "aqueous humor" is constantly produced inside the eye. In a healthy eye, this fluid leaves through microscopic channels called the "trabecular meshwork" in the anterior chamber and enters the bloodstream. There is a perfect balance between production and drainage, which keeps the intraocular pressure (IOP) at normal levels (usually between 10-21 mmHg).

Glaucoma is a disease where fluid accumulates inside the eye due to blockage or resistance in these drainage channels. The accumulated fluid gradually increases the pressure within the closed system of the eyeball. This elevated pressure exerts mechanical stress on the optic nerve, which consists of millions of nerve fibers and provides communication between the eye and the brain, while also compressing the capillaries that nourish it. Nerve fibers that are deprived of oxygen and crushed begin to die over time. Since dead nerve cells cannot regenerate, vision loss caused by glaucoma is strictly permanent and irreversible.

What are the Subtypes of Glaucoma?

Glaucoma is not a single type of disease; it is divided into different subgroups based on the anatomical cause preventing drainage:

1. Primary Open-Angle Glaucoma: The most common type worldwide (about 90% of cases). Although the drainage angle is open, there is resistance at the cellular level in the microscopic channels. Pressure rises very slowly and stealthily, destroying the optic nerve over years without symptoms.
2. Angle-Closure Glaucoma (Closed-Angle Glaucoma): This occurs when the iris (the colored part of the eye) suddenly and completely covers the drainage angle. Like a drain being blocked by a stopper, fluid is trapped, and pressure can soar to dangerous levels (40-60 mmHg) within minutes. This is a medical emergency characterized by severe pain and sudden vision loss.
3. Normal-Tension (Normotensive) Glaucoma: A stealthy type where the optic nerve is damaged and the visual field narrows despite intraocular pressure appearing within "normal" limits (21 mmHg and below). This is often due to genetic sensitivity of the optic nerve or vascular insufficiency.
4. Secondary Glaucomas: High eye pressure resulting from other conditions or external factors such as eye trauma, advanced diabetic retinopathy, intraocular inflammation (uveitis), tumors, or long-term uncontrolled steroid use.

Risk Factors: Who is at Risk?

While glaucoma tends to appear after the age of 40, individuals with specific risk factors must be extra vigilant:

1. Genetics and Family History: People with a family history (parents, siblings) of glaucoma have a 6 to 8 times higher risk than the general population.
2. Advanced Age: Risk increases gradually after 40 and is significantly higher over 60.
3. Thin Cornea Structure: A naturally thin central cornea is an important indicator that the optic nerve may be more fragile against pressure.
4. High Myopia and Hyperopia: High myopes are at risk for open-angle glaucoma, while high hyperopes (due to smaller eye structure) are at risk for closed-angle crises.
5. Systemic Diseases: Diabetes, hypertension, severe migraines, and blood circulation disorders are primary medical conditions that increase risk.

What are the Symptoms of Glaucoma?

The most frightening feature of open-angle glaucoma is that it creates no pain or blurring until the advanced stages. The disease slowly narrows the visual field from the edges (peripheral vision) toward the center. Due to the brain's ability to "fill in" images, a person may not notice this loss for years. By the time the patient experiences "tunnel vision," more than 80% of the optic nerve fibers may already be dead.

However, in an acute Angle-Closure Crisis, the following severe symptoms appear within seconds:

1. Unbearable pain in the eye and the corresponding side of the head.
2. Sudden blurring and loss of vision.
3. Seeing rainbow-colored rings (halos) around lights.
4. Extreme redness in the eye.
5. Severe nausea and vomiting due to high pressure.

Early Diagnosis with the World's Most Advanced Technologies

Since vision lost to glaucoma cannot be restored, our only weapon is "early diagnosis." At our clinic, we apply advanced structural and functional tests:

1. Tonometry: Precise measurement of intraocular pressure.
2. Pachymetry: Measurement of corneal thickness, which is essential to calculate the true impact of the measured pressure.
3. Optical Coherence Tomography (OCT): A 3D, high-resolution scan of the optic nerve head and Retinal Nerve Fiber Layer (RNFL). This technology can detect nerve thinning years before visual field loss begins.
4. Computerized Visual Field Test (Perimetry): Functional mapping that detects blind spots (scotomas) in peripheral vision that the patient cannot yet perceive.
5. Gonioscopy: Microscopic examination using special lenses to determine if the drainage channels are open or closed.

Treatment Methods for Glaucoma

The sole aim of glaucoma treatment is to protect current vision for life by lowering intraocular pressure to a safe level (target pressure) that will not damage the optic nerve.

1. Medical (Drug) Treatment

The first step usually involves special eye drops that must be used regularly every day for life. These drops lower pressure by either reducing fluid production (e.g., beta-blockers) or increasing fluid drainage (prostaglandins).

2. Laser Treatments

Effective and painless methods used when drops are insufficient or cause side effects:

1. Selective Laser Trabeculoplasty (SLT): In open-angle glaucoma, a low-energy laser is applied to the drainage channels to help the fluid filter out more easily.
2. YAG Laser Iridotomy: To eliminate the risk of closed-angle glaucoma, a microscopic hole is created in the iris to form a bypass for fluid circulation.

3. Surgical Treatments (Surgery)

If pressure cannot be lowered despite drops and lasers, surgery is the only option. Methods successfully performed by Dr. Ayşe Öner include:

1. Trabeculectomy: The gold standard of glaucoma surgery, creating a new drainage window through microsurgery.
2. Tube Implants (Seton Surgery): Preferred in resistant or secondary glaucoma cases, placing a biocompatible silicone tube (e.g., Ahmed Glaucoma Valve) to drain fluid.
3. Minimally Invasive Glaucoma Surgery (MIGS): A next-generation approach using smaller incisions and modern devices, often combined with cataract surgery for early-stage patients.

Do not allow your visual field to darken or the colors of the world to disappear. In the fight against glaucoma, there is not a single day to lose. Contact our patient unit immediately to control your eye pressure with the most advanced technology and unique health comfort.