It’s the result of high fluid pressure inside your eye. This happens when the liquid in the front part of the eye doesn’t distribute the way it should.
Normally, the fluid, called liquid humor, flows out of your eye through a mesh-like channel. If this channel gets obstructed, the liquid develops. That’s what causes glaucoma. The reason for the clog is unidentified, but medical professionals do understand it can be acquired, suggesting it’s passed from parents to children.
Hidden reasons for this imbalance usually connect to the type of glaucoma you have.
Simply as a basketball or football needs air pressure to preserve its shape, the eyeball requires internal fluid pressure to maintain its globe-like shape and ability to see.
However when something affects the capability of internal eye structures to manage intraocular pressure (IOP), eye pressure can rise to dangerously high levels – causing glaucoma.
What Are the Main Reasons of Glaucoma in Human?
Unlike a ball or balloon, the eye cannot alleviate pressure by springing a leak and “deflating” when pressure is too expensive. Rather, high eye pressure just keeps structure and pressing versus the optic nerve until nerve fibers are permanently damaged and vision is lost.
Glaucoma and Eye Anatomy
When glaucoma progresses, injury to neurons eventually results in eye damage through peripheral vision loss. Nevertheless, eye damage appears to begin first in the brain as connection is lost.
This discovery reported in early 2010 is a significant advancement that might result in improved early diagnosis and treatments of the eye disease, according to Vanderbilt Eye Institute (VEI) researchers in Nashville.
“If you followed the disease long enough, eventually the optic nerve, then the retina, show signs of degeneration,” stated VEI research director David Calkins, PhD. “So the degeneration works in reverse order. It begins in the brain and works its way back to the retina …”
To comprehend what causes glaucoma, you first must understand something about the human eye’s anatomy and how intraocular fluid moves through the eye:
- The clear fluid inside the eye is produced by the ciliary body, which is a small, circular structure found behind the iris or colored part of the eye.
- This fluid, known as the liquid humor, flows behind the iris and through the student or main opening in the middle of the iris. The aqueous humor (or “aqueous”) then fills the anterior chamber, a space in between the back of the clear cornea and the front of the iris.
- The aqueous exits the eye through a structure called the drainage angle, which is the angle formed inside the anterior chamber in between the iris and the peripheral cornea.
- The liquid filters through this angle and through the sclera or white part of the eye then joins with the network of veins outside the eye.
- Any disruption of this outflow of aqueous – including from specific eye injuries– can lead to an increase in IOP.
Anatomically, the eye’s drainage angle is described as being either “open” or “closed” (narrow). The narrower the angle, the more difficult it is for the aqueous to stream through it.
An open angle likewise can impede the outflow of aqueous, if structural damage exists within the ocular tissues of the angle itself.
Other Glaucoma Causes: Poor Blood Flow, Optic Nerve Damage
While high IOP frequently is connected with glaucoma, this eye disease likewise can happen when internal eye pressure is normal (normal-tension glaucoma). People with this condition have highly pressure-sensitive optic nerves that are vulnerable to permanent damage from what generally would be thought about “normal” IOP.
On the other hand, certain people with raised intraocular pressure called ocular hypertension may never ever establish glaucoma.
Most standard approaches of evaluating for glaucoma involve screening eyes for the presence of high IOP. But since glaucoma can happen even without high IOP, direct assessment of the optic nerve and visual field testing are essential in making (or ruling out) the diagnosis of glaucoma.
Though the exact reason for normal-tension glaucoma is unidentified, lots of researchers think decreased blood flow to the optic nerve might be a factor. This could be brought on by narrowing of blood vessels that nurture the optic nerve or constraints of these vessels (vasospasms).
Some studies likewise suggest that poor blood flow within the eye is related to blind spots (scotomas) that establish within the visual field, just like those that occur in glaucoma.
An intriguing research study reported in August 2007 shows a prospective typical cause of both glaucoma and Alzheimer’s, which produces brain sores and accompanying amnesia.
Researchers in the UK who conducted the research study discovered that buildup of a protein referred to as beta-amyloid in the eye’s retina and in brain tissue seems connected with development of both glaucoma and Alzheimer’s.
Nevertheless, abnormal build-up of beta-amyloid proteins does not indicate that someone with Alzheimer’s will have glaucoma or vice versa. Scientist said similarities in between certain eye and brain tissue could discuss why the buildup of beta-amyloid proteins can affect both the eye and the brain.
Increasingly, glaucoma treatments now are being investigated for their capability to protect nerve cells in the eye from damage.