Glaucoma : What is Eye Pressure and Why We Need Eye Pressure Testing?
Eye pressure, also known as intraocular pressure (IOP), refers to the fluid pressure inside the eye. The eye maintains a balance between the production and drainage of a clear fluid called aqueous humor. When this balance is disrupted, pressure can build up, potentially damaging the optic nerve, which is crucial for vision.
What is Eye Pressure?
Eye pressure, also known as intraocular pressure (IOP), refers to the fluid pressure inside the eye. The eye maintains a balance between the production and drainage of a clear fluid called aqueous humor. When this balance is disrupted, pressure can build up, potentially damaging the optic nerve, which is crucial for vision.
Why is Eye Pressure Important in Glaucoma?
Glaucoma is a group of eye diseases that cause progressive optic nerve damage, often due to high intraocular pressure. If left untreated, it can lead to permanent vision loss. However, some people develop glaucoma even with normal eye pressure (normal-tension glaucoma), while others have high IOP without damage (ocular hypertension).
What is Glaucoma?
Glaucoma is a group of eye diseases that cause progressive optic nerve damage, often due to high intraocular pressure. It is one of the leading causes of irreversible blindness worldwide.
Types of Glaucoma:
Primary Open-Angle Glaucoma (POAG)
- The most common type (90% of cases).
- Drainage channels gradually clog, raising pressure slowly.
- No early symptoms—vision loss occurs silently.
Angle-Closure Glaucoma (Acute Glaucoma)
- Sudden blockage of fluid drainage, causing a rapid IOP spike.
- Symptoms: Severe eye pain, headache, nausea, blurred vision.
- A medical emergency requiring immediate treatment.
Normal-Tension Glaucoma (NTG)
- Optic nerve damage occurs even with “normal” IOP.
- Causes may include poor blood flow to the optic nerve.
Secondary Glaucoma
- Caused by other conditions (diabetes, eye injuries, steroids).
Why is an Eye Pressure Test Necessary?
Since glaucoma often has no early symptoms, regular eye pressure checks are crucial for early detection and prevention of vision loss.
Key Reasons for Eye Pressure Testing:
Early Detection of Glaucoma
- Many people with high IOP feel no pain or vision changes until significant damage occurs.
- Regular screenings help catch glaucoma before irreversible harm.
Monitoring Glaucoma Progression
- If diagnosed, frequent IOP tests ensure treatments (eye drops, laser, surgery) are working.
Identifying Ocular Hypertension (High IOP Without Damage)
- Some people have elevated IOP but no optic nerve damage (yet).
- They may need preventive treatment to avoid future glaucoma.
Assessing Risk Factors
- Age (over 40), family history, diabetes, and thin corneas increase glaucoma risk.
- Regular pressure checks help manage these risks.
How is Eye Pressure Measured?
Several methods are used to check IOP:
A. Tonometry (Eye Pressure Tests)
- Goldmann Applanation Tonometry (GAT – Gold Standard)
- Uses a special device (attached to a slit lamp) to gently flatten the cornea and measure resistance.
- Requires numbing drops and a fluorescein dye.
- Non-Contact Tonometry (NCT – “Air Puff Test”)
- A quick, painless blast of air measures corneal resistance.
- Often used in routine screenings.
- Pascal Dynamic Contour Tonometry (DCT)
- More advanced, accounts for corneal thickness.
B. Additional Glaucoma Tests
- Optic Nerve Imaging (OCT, HRT) – Detects nerve damage.
- Visual Field Test – Checks for peripheral vision loss.
- Pachymetry – Measures corneal thickness (thinner corneas can underestimate IOP).
Treatment & Management of Glaucoma
While glaucoma damage is irreversible, early treatment can slow or stop progression.
Treatment Options:
✔ Medicated Eye Drops (Prostaglandins, Beta-blockers) – Reduce fluid production or improve drainage.
✔ Laser Therapy (SLT, ALT) – Helps open drainage channels.
✔ Surgery (Trabeculectomy, MIGS, Drainage Implants) – Creates new fluid drainage pathways.
LJ Eye Institute, Patiala – Advanced Glaucoma Care
LJ Eye Institute in Patiala is a leading center for glaucoma diagnosis and treatment, offering:
- Accurate IOP Measurement (Goldmann tonometry, NCT)
- Advanced Imaging (OCT, Visual Field Testing)
- Laser & Surgical Treatments (SLT, Trabeculectomy)
- Personalized Glaucoma Management Plans