Glaucoma is one of the leading causes of blindness in the world. Around 2% of the population suffer from this disorder. Unlike cataract, visual loss caused by Glaucoma is not reversible. But fortunately early diagnosis and treatment can prevent visual loss.
What is Glaucoma ?
Glaucoma is a disease in which your optic nerve (nerve that transmits visual information to the brain) is damaged because of changes in the pressure inside your eyes. It may be 2 kinds : Open Angle and Angle Closure (Acute).
What causes it ?
The passages in your eye that normally drain the fluid out of your eyes become clogged. This pent up fluid now raises the pressure in your eye and on the optic nerve causing damage and hence loss of vision. An injury, infection or tumour in or around your eye can also cause the pressure to rise. The following factors put you at risk :
- Having a family history of Glaucoma
- High blood pressure or other diseases of the blood vessels
- Long term steroid use
- Above the age of 40 years
What are the symptoms ?
Usually Glaucoma is asymptomatic but following symptoms can be present in various cases :
- Heaviness or headache
- Gradual darkening at outer edge of vision
- Appearance of coloured rings around lights
- Pain and redness in eyes
Can glaucoma exist even if the patient feels his vision is normal ?
Glaucoma affects the peripheral vision first, i.e. the top, sides and bottom areas of vision and finally the central vision is affected. So the patient may feel that his vision is absolutely normal.
What is angle closure Glaucoma ?
Here the drainage angle is narrow and this can lead to increased intraocular pressure. Sometimes this angle may get closed leading to a sudden high rise in intraocular pressure called acute angle closer Glaucoma, a painful condition. This needs emergency medical treatment followed by laser procedure.
What is normal tension Glaucoma ?
It is a form of Glaucoma in which optic nerve damage occurs even though intraocular pressure within normal range.
What is secondary Glaucoma ?
Secondary Glaucoma can occur due to other disease processes in the eye or due to treatment of other eye conditions
How is Glaucoma diagnosed ?
Usually, Glaucoma is discovered during routine eye examination. The tests used to diagnose and monitor progression of Glaucoma include.
- Tonometry: To measure intraocular pressure
- Gonioscopy : To view the angle structure of the eye
- Ophthalmoscopy: To view the optic nerve head changes
- Pachymetry: To check the corneal thickness
- Perimetry / visual fiels test : To map the field of vision of each eye
- OCT (Optical Coherence Tomography) : to analyse in detail optic nerve changes, retinal nerve fibre layer loss , ganglion cell layer loss in all stages of Glaucoma.
What are the treatment options available ?
Medication: This includes eye drops which have to be used permanently as advised by the doctor. These either decrease the production of fluid in the eye or increase the drainage of fluid from the eye. Thus leading to a decrease in intraocular pressure.
Laser: Special laser is used to create a bypass channel for fluid communication between anterior and posterior chamber of the eye.
Surgery: This is necessary when eye drops can no longer control intraocular pressure.
What are the chances of recovery?
If one have open angle Glaucoma, proper treatment greatly decreases one’s risk of vision loss. If one have angle closure Glaucoma and it is neglected, one can become blind in that eye in 2 days or less. Timely treatment can return one’s vision to almost the previous level.
Does any particular diet help?
No, there is no evidence to prove that following a particular diet will treat or prevent Glaucoma.
If one have high eye pressure, does it mean that one have Glaucoma?
No, a high eye pressure without any optic nerve damage means that one are at a greater risk for Glaucoma and that one should undergo routine examinations.
Contact your doctor immediately if you have
Worsening of the vision
Severe pain with or without associated vomiting
Increasing redness of the operated eye
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