Eyes are the main organ of vision and a sense organ too.
Eyes have two chambers anterior chamber and posterior chamber. A Fluid called Aqueous humor circulates in eye and flows through channels that are formed like a mesh. It nourishes the eye tissues. Blockage of this channel; blocks proper drainage of this fluid rising intraocular pressure (pressure within the eyes called IOP).
Aqueous humor is produced by cilia of eyes (which are short microscopic hair-like vibrating structures which cause currents in the surrounding fluid). This fluid goes to the posterior surface bound by lens, enters the anterior chamber & finally gets drained by trabecular meshwork to the body's blood circulation.
This meshwork is located at the drainage angle of eye (where the clear surface of eye cornea is attached to the coloured part called iris). This angle can be very narrow in some people affecting the drainage.
Excess production or deficient drainage can increase the amount of Aqueous humor resulting in high IOP (Intraocular pressure). But it is important to remember that Glaucoma can happen even if IOP is normal.
Optic nerve is responsible for transmitting images to brain. It is the main nerve innervating the eye. It consists of millions of nerve fibres. Retina is the sensitive tissue of eye which is connected to brain via optic nerve. Constant high pressure can damage the optic nerve, which can result in permanent loss of vision. There is damage of retinal ganglion cells of optic nerve. Usually pressure more than 21 mm of Hg is significant.
Glaucoma is often addressed as 'Silent thief of sight' because initially there are no symptoms and gradually over a period of time, vision is affected.
Glaucoma can be primary or secondary. Primary Glaucoma is mainly due to rise of intraocular pressure, which can be further open angle or angle closure Glaucoma. While; Secondary Glaucoma is due to certain medicines like steroids, diabetes, trauma to eyes, blood circulation problems, intraocular haemorrhages, infections.
Also constitutional homeopathic medicines remove the predisposition towards Glaucoma.