Glaucoma: Symptoms, Causes, Types & Treatment | Dream Savers Eye Clinic Lagos

Glaucoma is a group of eye disorders that damage the optic nerve, the key connection between your eye and brain and is a leading cause of irreversible blindness worldwide. The damage often occurs slowly and painlessly, so many people don’t notice vision loss until the disease is advanced. Early detection and consistent treatment dramatically reduce the risk of sight loss. This guide explains everything you and your patients need to know about glaucoma: how to recognise it, what causes it, the types you must watch for, how we diagnose it, and the full range of treatment options available today.

What is Glaucoma?

Glaucoma refers to a set of conditions characterized by progressive optic nerve damage, frequently associated with elevated intraocular pressure (IOP). Over time, the optic nerve fibers die and the visual field (peripheral vision) gradually shrinks, often without pain or early symptoms. Left untreated, glaucoma can lead to permanent vision loss and blindness. While raised eye pressure is a major risk factor, glaucoma can occur even at normal pressures.

Types of Glaucoma (Detailed)

1. Primary Open-Angle Glaucoma (POAG)

• Most common form, especially among adults over 40.
• The drainage angle (where aqueous fluid leaves the eye) remains open, but microscopic drainage channels become less efficient.
• Onset is slow and painless, often called the “silent thief of sight.”

2. Angle-Closure Glaucoma (Acute or Chronic)

• Occurs when the drainage angle becomes physically blocked, can be acute (sudden and painful, medical emergency) or chronic (slower but still dangerous).
• Acute angle-closure causes sudden severe eye pain, nausea, vomiting, and rapid vision loss, urgent treatment needed.

3. Normal-Tension Glaucoma (NTG)

• Optic nerve damage occurs despite normal measured eye pressure.
• Believed to result from poor blood flow to the optic nerve, structural susceptibility, or other systemic factors (e.g., low blood pressure at night).

4. Congenital & Developmental Glaucoma

• Present at birth or early childhood due to abnormal eye development.
• Signs include excessive tearing, light sensitivity, and enlargement of the eye (buphthalmos).

5. Secondary Glaucoma

• Caused by another eye condition, injury, inflammation, or medication (e.g., prolonged steroid use).
• Examples: neovascular glaucoma (from diabetes), pigmentary glaucoma, uveitic glaucoma, traumatic glaucoma.

Causes & Risk Factors

Glaucoma results from a combination of mechanical, vascular, and structural factors. Major causes and risk factors include:

• Raised intraocular pressure (IOP): most important modifiable risk factor.
• Age: risk rises after 40 and increases further after 60.
• Family history / Genetics: strong hereditary component.
• Race/Ethnicity: higher prevalence and more aggressive disease in people of African descent (higher risk of POAG), and in certain Asian populations for angle-closure glaucoma.
• High myopia (severe nearsightedness).
• Thin central corneal thickness: increases risk and affects IOP measurement.
• Systemic diseases: diabetes, hypertension, migraine, sleep apnea.
• Vascular factors: poor optic nerve perfusion, nocturnal hypotension.
• Ocular trauma, previous eye surgery, or inflammation.
• Prolonged steroid use (topical, inhaled, or systemic) can raise IOP and cause secondary glaucoma.

Symptoms

Glaucoma symptoms depend on type and stage. Many forms are initially asymptomatic, so screening is crucial. Here’s what to watch for:

Early/Chronic Symptoms (often subtle)

• Gradual loss of peripheral (side) vision, often unnoticed until advanced.
• Difficulty seeing in dim light.
• Frequent changes in glasses prescription.
• Mild eye discomfort or heaviness (uncommon).

Acute/Severe Symptoms (urgent)

• Sudden severe eye pain (especially with angle-closure).
• Severe headache, nausea, and vomiting.
• Blurred vision, seeing halos around lights.
• Rapid vision loss in one eye emergency.

Other signs

• Tunnel vision in late stages.
• Normal-tension glaucoma may present with progressive visual field loss without raised IOP.

Key point: any sudden visual changes, flashes, severe pain, or nausea with eye symptoms must be evaluated immediately.

Diagnosis & Tests (Comprehensive)

Accurate glaucoma diagnosis uses a combination of tests — no single test can diagnose glaucoma by itself.

1. Comprehensive Eye Exam: medical and family history plus symptoms review.
2. Visual Acuity: standard sight test.
3. Tonometry: measures Intraocular Pressure (IOP). Several devices available (applanation, non-contact).
   
4. Gonioscopy: examines drainage angle to classify open vs angle-closure glaucoma.
5. Optic Nerve Examination (Fundoscopy): direct visualization of the optic disc for cupping and nerve fiber loss.
6. Visual Field Testing (Perimetry):  maps peripheral vision loss, essential to track functional damage.
7. Optical Coherence Tomography (OCT): high-resolution imaging of the retinal nerve fiber layer and ganglion cell complex; detects structural loss before field defects appear.
8. Pachymetry: measures central corneal thickness (influences IOP interpretation).
9. Anterior Segment Imaging / Ultrasound Biomicroscopy: useful for angle assessment.
10. Blood pressure and systemic evaluation: to identify vascular contributors.
11. Additional tests for secondary causes (e.g., blood glucose for diabetic neovascular glaucoma).

At Dream Savers Eye Clinic we combine history, cutting-edge imaging (OCT), visual fields, and experienced clinical assessment for precise diagnosis and staging.

Treatment Options

Treatment goals

• Lower IOP to a target level that slows or stops optic nerve damage.
• Preserve vision and quality of life.
• Minimize treatment side effects.

1. Medical Therapy (Eye Drops & Systemic Meds)

• Prostaglandin analogues (e.g., latanoprost, travoprost),  often first-line; increase aqueous outflow.
• Beta-blockers (timolol):  reduce aqueous production.
• Alpha-agonists (brimonidine): reduce production and increase outflow.
• Carbonic anhydrase inhibitors (topical or oral):  reduce aqueous production.
• Miotics (pilocarpine):  sometimes used in angle-closure or to improve outflow.

Medication adherence is critical,  missed doses increase progression risk. Side effects vary per class; monitoring and counseling improve compliance.

2. Laser Treatments

• Selective Laser Trabeculoplasty (SLT)commonly used for open-angle glaucoma to improve drainage; can be first-line or adjunctive.
• Argon Laser Trabeculoplasty (ALT): older technique, similar aim.
• Laser Peripheral Iridotomy (LPI): creates a small hole in the peripheral iris to relieve pupillary block in angle-closure glaucoma (emergency or prophylactic for narrow angles).
• Cyclophotocoagulation (laser to ciliary body): used when other measures fail to reduce aqueous production.

Laser is minimally invasive, repeatable, and often reduces medication dependence.

3. Surgical Procedures

Reserved for uncontrolled glaucoma or when laser/meds aren’t enough.

• Trabeculectomy: creates a new drainage pathway (bleb),  gold standard for many years.
• Glaucoma Drainage Devices / Tubes (e.g., Ahmed, Baerveldt): shunt devices to divert aqueous to a reservoir.
• Minimally Invasive Glaucoma Surgery (MIGS): e.g., iStent, Hydrus, canaloplasty, safer, faster recovery, often combined with cataract surgery; best for mild-to-moderate glaucoma.
• Goniotomy / Trabeculotomy: used in congenital and some secondary glaucomas.
• Cyclodestructive procedures: reduce aqueous production in refractory cases.

Each surgical choice depends on disease severity, patient health, life expectancy, and risk tolerance. Post-op follow-up is essential to monitor pressure, bleb function, and complications.

4. Treatment for Secondary & Congenital Glaucoma

• Treat underlying cause (e.g., control neovascularization in diabetic eye disease).
• Early surgery in congenital glaucoma is often needed.

Monitoring & Long-Term Management

Glaucoma is chronic. Long-term management includes:

• Regular clinic visits with IOP checks, OCT scans, and visual fields.
• Medication adherence and side-effect monitoring.
• Lifestyle advice (avoid excessive Valsalva, maintain cardiovascular health).
• Education about symptoms requiring urgent review.
• Family screening, first-degree relatives have higher risk.

Prevention & Risk Reduction

While some risk factors (age, genetics) are fixed, you can reduce risk/progression by:

• Getting regular eye exams (especially if age >40, family history, diabetic).
• Controlling systemic conditions (diabetes, hypertension).
• Avoiding long-term unmonitored steroid use.
• Protecting eyes from injury and UV exposure.
• Maintaining a healthy lifestyle (diet, exercise, smoking cessation).

When to See an Eye Doctor (Urgent Red Flags)

Seek immediate care if you experience:

• Sudden severe eye pain with vomiting or headache.
• Sudden loss of vision or rapid change in vision.
• Seeing halos, severe redness with blurred vision.
• Sudden increase in floaters or flashes (possible retinal detachment).

Otherwise, routine glaucoma checkups depend on severity, often every 3–12 months.

Living with Glaucoma (Practical Advice)

• Set medication reminders and review prescriptions regularly.
• Bring a list of meds and allergies to visits.
• Inform other healthcare providers about glaucoma meds (some systemic meds interact).
• Get family members screened.
• Consider low-vision services if visual field loss affects daily life.

Glaucoma is treatable, if detected early. Regular screening, proper diagnosis, and an individualized treatment plan can preserve vision and quality of life.

If you or a family member have risk factors or any concerns about vision, contact Dream Savers Eye Clinic for expert glaucoma screening, modern diagnostic imaging (OCT, visual fields), and full-spectrum glaucoma care, from medical management and laser to advanced surgical options.

Book your glaucoma screening and comprehensive eye exam today:

Protect your sight, early detection saves vision.