Front part of the eye, the anterior chamber, is filled with fluid (aqueous humor). Normally, the fluid drains out of the eye through a sieve (trabecular meshwork) located in the angle of the anterior chamber (the internal junction between the iris and the cornea). If the drainage of this fluid from the anterior chamber is restricted, pressure builds up within the eye causing irreversible damage to the optic nerve thereby causing a permanent loss of vision.

What are the types of Glaucoma?

There are several types of glaucoma all of which show an increased IOP and show damages on the optic nerve. Open angle glaucoma: There is an increase in resistance to the outflow in the drainage channel (trabecular meshwork) which causes a rise in the IOP. This type develops gradually and patient may have a loss of peripheral vision, leaving only central or ‘tunnel’ vision. This occurs more amongst people above 45 years of age. Angle closure glaucoma: There is a relative block to the flow of fluid by the iris blocking the drainage channel in the angle, which causes raised pressure. Stress, anxiety, and reading may also precipitate an attack, which may resolve on its own, but recur after some time. Developmental glaucoma: which may be further divided into: 1. Congenital glaucoma in infants from the time of birth) and 2. Juvenile glaucoma (occurs in children and young adults). Secondary Glaucoma: Occurs due to other causes such as the use of steroid drops without prescription, following trauma (injury) to the eye, or sometimes due to some conditions inside the eye (neovascular glaucoma due to venous occlusions)

What are the symptoms of Glaucoma?

Most types of glaucoma remain asymptomatic until advanced stage and that is why glaucoma is termed as the “silent thief of sight”. Hence periodical checkup, especially for those at risk, is necessary to detect glaucoma early. Some individuals, especially if there is a rapid buildup of eye pressure, may experience one or more of the following symptoms: