Glaucoma – particularly Primary Open-Angle Glaucoma (POAG) – is one of the leading causes of irreversible blindness globally. Known as the “silent thief of sight,” this chronic condition progresses without early symptoms, making regular eye examinations vital for early detection and vision preservation.
What Is Open-Angle Glaucoma?
Open-angle glaucoma occurs when pressure builds up inside the eye due to improper drainage of intraocular fluid. Over time, this pressure damages the optic nerve, which is essential for sending visual information from the eye to the brain.
Unlike angle-closure glaucoma, POAG develops slowly and painlessly, often without noticeable symptoms until significant vision loss has already occurred.
Signs and Symptoms
Because open-angle glaucoma affects peripheral (side) vision first, most people remain unaware of the condition in its early stages. As the disease progresses, symptoms may include:
- Loss of peripheral vision
- Tunnel vision in advanced stages
- Blind spots in the field of vision
- Frequent changes in eyeglass prescriptions
Unfortunately, central vision is only affected in the late stages, which is why many patients do not realise there’s an issue until extensive damage has occurred.
Who’s at Risk?
Everyone is at risk, but the following factors significantly increase the likelihood of developing POAG:
- Age: People over 60
- Family history of glaucoma
- African or Latino descent
- High eye pressure (intraocular pressure or IOP)
- Thin corneas
- Medical conditions such as diabetes, hypertension, and myopia
- Use of corticosteroid medications
- Previous eye injuries
Because the condition can be hereditary and progresses without pain, it’s essential to schedule eye exams at least annually—especially if you’re in a high-risk category.
Diagnosis and Monitoring
Detection of open-angle glaucoma requires a comprehensive eye examination, including:
- Tonometry to measure intraocular pressure
- Ophthalmoscopy to inspect the optic nerve
- Visual field testing to detect peripheral vision loss
- Pachymetry to measure corneal thickness
Monitoring these values over time helps eye care professionals determine disease progression and effectiveness of treatment.
Treatment Options
While there’s currently no cure for glaucoma, the damage can be significantly slowed or halted with appropriate intervention.
The main goal of treatment: Lower the intraocular pressure (IOP)
1. Medication (Eye Drops)
- Prostaglandin analogues: e.g., latanoprost, travoprost – often first-line treatment due to once-daily dosage and effectiveness
- Beta-blockers: e.g., timolol – useful in younger patients or unilateral glaucoma
- Alpha agonists, carbonic anhydrase inhibitors, and miotics are additional or adjunctive options
2. Laser Therapy
- Selective Laser Trabeculoplasty (SLT) is commonly used to enhance fluid drainage
3. Surgery
- In severe cases, surgical procedures like trabeculectomy or drainage implants may be considered
The Importance of Regular Eye Exams
Glaucoma doesn’t wait for symptoms to become obvious—it quietly progresses until the damage is permanent. That’s why routine eye check-ups, especially after age 40 or if you’re at high risk, are non-negotiable in preserving your sight.
“Vision lost to glaucoma cannot be restored, but early detection and consistent treatment can save what remains.”
