Glaucoma is a group of diseases caused by degeneration of the optic nerve, characterized by increased intraocular pressure and loss of peripheral vision, which can severely affect sight. It is a significant cause of permanent blindness that cannot be reversed, even with surgical treatment. Currently, the most effective approach is to control the progression of the disease from the time of diagnosis. However, glaucoma can be prevented if detected early; the sooner it is diagnosed, the better the chance of preserving vision.
Understanding glaucoma
Glaucoma can affect individuals of any age, but it is more commonly found in older adults, particularly those between 40 and 60 years old, especially if there is a family history of glaucoma, high myopia or hyperopia, diabetes, or vascular diseases. Individuals using steroid eye drops should also have their intraocular pressure and optic nerve health monitored regularly, ideally every 1 to 5 years. Glaucoma is the second leading cause of blindness, following cataracts, and is caused by high intraocular pressure that damages the optic nerve, leading to vision loss.
Types of glaucoma
- Angle-closure glaucoma: This type is less common than open-angle glaucoma. It occurs when the iris blocks the drainage angle of the eye, causing a sudden increase in intraocular pressure. Symptoms include severe eye pain, blurred vision, red eyes, inability to open the eyes, rainbow halos around lights, and gastrointestinal symptoms like nausea and vomiting. This type can be treated effectively if medical attention is sought quickly; however, if left untreated for more than 2-3 days, it can lead to blindness.
- Primary open-angle glaucoma: This is the most common type, characterized by gradual loss of the optic nerve. It is caused by blockage of the trabecular meshwork, leading to increased intraocular pressure without initial symptoms. Most patients are unaware they have it until significant vision loss has occurred. Early diagnosis is crucial to preserving remaining vision, but currently, there is no definitive cure for this type of glaucoma.
Many individuals do not realize they have glaucoma until they see an ophthalmologist, especially in chronic cases that progress slowly.
Risk factors for glaucoma
- African American descent, which is 6-8 times more likely to develop glaucoma compared to Caucasians.
- Age over 40.
- Family history of glaucoma.
- Previous eye injuries.
- Use of steroid medications. Other risk factors include high or low myopia, thin corneas, diabetes, and migraines.
Treatment for glaucoma
As glaucoma causes permanent damage to the optic nerve, treatment aims to preserve existing vision and prevent further damage. The approach depends on the type and stage of the disease. For acute glaucoma, prompt treatment by an ophthalmologist is essential to lower eye pressure to normal levels before irreversible changes occur in the optic nerve.
Treatment options include
- Medications: Various eye drops are available to reduce intraocular pressure by decreasing fluid production or improving drainage. Patients must use these drops consistently as prescribed, with follow-up appointments to monitor progress and side effects.
- Laser treatment: The type of laser used depends on the glaucoma type and stage.
- Surgery: This is considered for patients whose pressure cannot be controlled with medications or laser treatments. Surgical options include creating a new drainage pathway or inserting drainage tubes.
Monitoring and follow-up
Monitoring frequency depends on the individual’s condition. If the treatment response is uncertain, follow-up appointments may be scheduled every 1-2 months. For those whose condition is well-controlled and stable, appointments may be spaced out to every 4 months.
Precautions with glaucoma medications
Most eye drops are prescribed to be used once daily at bedtime, as newer medications are effective for 24 hours. Using more than the prescribed amount can lead to complications, including inflammation and worsening intraocular pressure. The ophthalmologist will tailor medication choices based on the patient’s condition, aiming to use the simplest regimen to encourage long-term adherence. Additionally, regular monitoring of intraocular pressure is essential to ensure the effectiveness of the chosen treatment and to watch for any potential side effects.
