What is Glaucoma?
Glaucoma is a serious eye condition that occurs due to damage to the optic nerve, commonly caused by increased pressure within the eye. Because it usually exhibits no symptoms in its early stages but can lead to permanent vision loss, glaucoma impacts millions of people around the world every year.
Types of Glaucoma and Their Symptoms
Primary Open-Angle Glaucoma
In this most common form of glaucoma, the drainage system of the eye known as the trabecular meshwork becomes clogged. Fluid builds up, resulting in increased intraocular pressure that can damage the optic nerve.
Symptoms: Usually none in early stages. Gradual vision loss starting from the periphery if left untreated.
Angle-Closure Glaucoma
This less common form of glaucoma arises when the iris blocks the drainage angle between the cornea and iris. Fluid can't circulate, leading to increased eye pressure.
Symptoms: Can range from severe headaches and eye pain in acute cases to minimal or no symptoms in chronic cases.
Additional Types
- Normal-Tension Glaucoma: Occurs even with eye pressure below 22 mmHg. Risk factors include family history, cardiovascular disease, and low night-time blood pressure.
- Congenital Glaucoma: Present in babies and children, rare but severe.
- Secondary Glaucoma: Caused by underlying conditions like eye injury or advanced cataracts.
- Glaucoma Suspect: Optic nerve or visual field appears at risk, requiring ongoing monitoring.
Mechanism Behind Glaucoma
The eye produces a fluid known as intraocular fluid or aqueous humour. This fluid should flow out through a drainage system, but in glaucoma, this system becomes blocked, causing high pressure inside the eye, damaging the optic nerve as a result.
Role of Eye Pressure in Glaucoma
Normal eye pressure ranges from 5-22 mmHg. Any pressure above this range is considered abnormally high and becomes a critical risk factor for developing glaucoma.
Risk Factors for Glaucoma
- Ethnicity: Higher risk in people of African, Asian, and Caucasian descent.
- Age: Those 40 years or older.
- Family history.
- Pre-existing high eye pressure.
- Previous eye injuries.
- Use of steroid medications.
- Other factors: High degree of myopia or hyperopia, thin cornea, diabetes, migraines.
Glaucoma Prevention Strategies
Though glaucoma can't be completely prevented, its impact on vision can be minimised through early diagnosis and treatment.
- Yearly eye examinations for people over 40.
- Eye protection to prevent injuries.
- Moderate exercise like walking or jogging to reduce eye pressure.
Treatment Approaches for Glaucoma
Medical Treatment
Medication is often prescribed to reduce eye pressure and prevent further optic nerve damage.
Laser Eye Surgery
The type of laser used for this treatment depends on the specific type and stage of glaucoma you have.
Surgical Options
Invasive surgical treatments may be considered for those who don't respond to medication or laser treatments.
Diagnostic Procedures
- Slit-lamp Microscopy Eye Exam
- Eye Pressure Test (Intraocular Pressure)
- Anterior Chamber Angle Exam
- Optic Nerve Examination
- Visual Field Test
