Glaucoma
This article is general health information for the selected condition. It is not a diagnosis and does not replace clinical judgement. If you have questions or need treatment advice, please consult a qualified healthcare professional.
What is glaucoma?
Glaucoma is a group of eye conditions that damage the optic nerve, usually in association with raised pressure inside the eye. The most common form is painless and takes peripheral vision first, so people often do not notice until substantial sight is lost. Vision already lost cannot be recovered, which is why screening and adherence to drops matter so much.
Causes
- Impaired drainage of aqueous fluid raising intraocular pressure
- Sudden blockage of the drainage angle in acute closure
- Optic nerve susceptibility even at normal pressures
- Secondary causes such as inflammation, trauma or steroids
Symptoms
- No symptoms in early chronic open angle glaucoma
- Gradual loss of peripheral vision
- Tunnel vision in advanced disease
- Severe eye pain and redness in acute angle closure
- Halos around lights
- Nausea and vomiting with acute attacks
- Sudden blurred vision in acute closure
Risk factors
- Age over 60
- Family history of glaucoma
- African or Caribbean ancestry for open angle disease
- East Asian ancestry for angle closure
- High myopia or hyperopia
- Diabetes
- Long term corticosteroid use
Diagnosis
- Measurement of intraocular pressure by tonometry
- Optic disc examination for cupping
- Visual field testing to map peripheral loss
- Optical coherence tomography of the nerve fibre layer
- Gonioscopy to assess the drainage angle
- Corneal thickness measurement
Treatment
- Prostaglandin analogue eye drops as usual first line
- Beta blocker or other pressure lowering drops
- Selective laser trabeculoplasty
- Laser iridotomy for angle closure
- Trabeculectomy or drainage device surgery
- Emergency pressure lowering for acute angle closure
Self care
- Use prescribed eye drops every day, even though vision feels unchanged
- Set reminders, since missed drops are the main reason treatment fails
- Learn correct drop technique and press gently on the inner corner afterwards
- Attend every scheduled eye appointment
- Tell any clinician about your glaucoma before starting new medicines
When to see a doctor
Book an appointment if:
- Difficulty tolerating or remembering your drops
- Any noticeable change in vision
- Family history of glaucoma, so relatives can be screened
- Before starting long term steroid treatment
- Routine eye tests at the recommended interval
Some symptoms need emergency care rather than an appointment. See the warning signs listed above.
Prevention
- Regular eye examinations, especially over 40 or with a family history
- Encourage first degree relatives to be screened
- Control blood pressure and diabetes
- Protect the eyes from injury
- Use corticosteroids only as directed and with monitoring
Outlook
Vision already lost cannot be recovered, but treatment that lowers eye pressure is highly effective at preventing further loss. Most people who are diagnosed early and use their drops consistently retain useful sight for life. Acute angle closure is different: it is an emergency, and sight depends on pressure being lowered within hours.
Common questions
Why is glaucoma called the silent thief of sight?
The common chronic form is painless and affects peripheral vision first. The brain compensates so effectively that people often notice nothing until a large proportion of nerve fibres has already been lost.
Can lost vision be restored?
No. Damage to the optic nerve is permanent. Treatment aims to lower pressure and preserve the vision that remains, which is why early detection through regular eye examinations is critical.
What is acute angle closure glaucoma?
A sudden blockage of eye drainage causing rapidly rising pressure, with severe eye pain, redness, blurred vision, halos and often vomiting. It is a medical emergency and needs treatment within hours to save sight.
References
Important: Dard AI is not a medical device and does not diagnose, treat, or replace clinician judgement. This article is general information only. Always consult a qualified healthcare professional about diagnosis and treatment, and seek emergency care for severe or rapidly worsening symptoms.