Glaucoma (Eye Pressure)

What is Glaucoma?
Glaucoma is a condition characterized by progressive damage to the optic nerve and a gradual loss of peripheral vision, often due to elevated or normal intraocular pressure.

Is Glaucoma a Dangerous Disease?
Glaucoma affects about 3 out of every 100 people. It can occur at any age but is often insidious, showing no symptoms until irreversible vision loss has occurred. It is a dangerous disease because it can lead to permanent blindness if untreated.

What Causes Glaucoma?
There are various types of glaucoma, but the common factor among all is that untreated cases will result in optic nerve damage and vision loss. While the exact causes remain unclear, the most significant risk factor known is high intraocular pressure. However, some people with normal eye pressure may still develop glaucoma due to poor circulation to the optic nerve, which may impair its nutrition. Therefore, normal eye pressure does not rule out the possibility of glaucoma, and further tests are required to diagnose it.

Types of Glaucoma:

• Primary Glaucoma Types:

  1. Primary Open-Angle Glaucoma: The most common and slow-progressing form of glaucoma, caused by resistance in the drainage channels within the eye. Often, there are no symptoms until later stages when blurry or reduced vision may occur.
  2. Normal-Tension Glaucoma: This type has no symptoms and normal intraocular pressure, but optic nerve damage and vision loss still occur.
  3. Ocular Hypertension: The eye pressure is elevated, but the optic nerve remains unaffected. Patients with thinner corneas need closer monitoring.
  4. Primary Angle-Closure Glaucoma: This form occurs when the drainage angle of the eye narrows, leading to acute pressure spikes, particularly in dark environments. It can lead to chronic damage if untreated. A procedure called YAG laser iridotomy is often used to open the angle and prevent pressure buildup.

• Secondary Glaucoma Types:

  1. Pseudoexfoliative Glaucoma: This type occurs when flakes of material from the eye's tissue block the drainage angle.
  2. Pigmentary Glaucoma: Pigment cells from dark-colored eyes accumulate in the drainage angle, obstructing fluid flow.
  3. Lens-Related Glaucoma: Cataracts can cause the lens to swell, blocking the drainage angle.
  4. Uveitic Glaucoma: Inflammation from uveitis causes the drainage angle to close.
  5. Tumor-Related Glaucoma: Intraocular tumors can block fluid drainage.
  6. Medication-Induced Glaucoma: Prolonged corticosteroid use can lead to increased intraocular pressure.
  7. Post-Hemorrhagic Glaucoma: Glaucoma caused by eye hemorrhage.

How is Glaucoma Treated?
Glaucoma requires lifelong monitoring. Treatment can reduce intraocular pressure, but it does not cure the disease. The goal of treatment is to slow or stop the damage to the optic nerve.

Treatment options include:

1. Medications: There are many medications to lower intraocular pressure, typically starting with one drug. If pressure is not sufficiently lowered, additional medications may be added.
2. Laser Therapy: Selective Laser Trabeculoplasty (SLT) is a recent, non-invasive treatment that can reduce intraocular pressure by up to 30%. SLT can be repeated and is commonly used for open-angle glaucoma. For angle-closure glaucoma, YAG laser iridotomy is performed to create a hole in the iris to alleviate pressure.
3. Surgical Treatment: If medication and laser therapies fail, surgery may be required. Trabeculectomy is a procedure where a small hole is created in the eye to allow fluid to drain, reducing pressure. However, surgery is considered a last resort due to its risks and lower success rate. In cases where surgery is unsuccessful, additional surgeries or drainage tubes may be needed.

Can Glaucoma be Prevented or Cured?
While glaucoma cannot be cured, it can often be controlled with early diagnosis and appropriate treatment. Regular eye exams are essential for detecting glaucoma, especially for individuals with risk factors such as family history, age, or high intraocular pressure.