Glaucoma is an eye disease in which the nerve that connects the eye to the brain (optic nerve) is damaged. In angle-closure glaucoma, the iris (the colored part of the eye) is pushed or pulled up against the trabecular meshwork (or drainage channels) at the angle of the anterior chamber of the eye. When the iris is pushed or pulled up against the trabecular meshwork, the fluid that normally flows out of the eye is blocked and cannot drain out, thereby increasing the IOP. If the angle closes suddenly, symptoms are severe and dramatic. Immediate treatment is essential to prevent optic nerve damage and vision loss.
If the angle closes intermittently or gradually, angle closure glaucoma may be confused with chronic open-angle glaucoma, another type of glaucoma. People of Asian and Eskimo ancestry are at higher risk of developing it. Age and family history are risk factors. It occurs in older women more often than others. When the pupil of the eye is wide open the iris is retracted and thickened and it block the canal of Schlemm, a key component of the drainage pathway for fluid within the eye. Blocking the drainage canal of Schlemm sends the pressure within the eye shooting up. There is an abrupt increase in intraocular pressure due to the buildup of aqueous in the eye.
The high pressure can damage the optic nerve and lead to blindness. The elevated pressure is best detected before the appearance of symptoms. That is why when the eyes are dilated in a doctor’s office for a refraction, eye pressures are checked. When symptoms of acute angle glaucoma do develop, they include severe eye and facial pain, nausea and vomiting, decreased vision, blurred vision and seeing haloes around light. The eye in a far advanced case of angle closure glaucoma appears red with a steamy cornea and a fixed dilated pupil.
Angle-closure glaucoma is glaucoma associated with a closed anterior chamber angle, which may be chronic or, rarely, acute. Angle-closure glaucoma accounts for about 10% of all glaucomas in the US. In Asia, angle-closure glaucoma is more common than open-angle glaucoma Certain races have narrow angles and, thus, are more likely to develop angle-closure glaucoma than whites. Angle-closure glaucoma among American Indians is lower than among whites. In whites, angle-closure glaucoma is 3 times higher in women than in men. In blacks, men and women are affected equally.
Find common causes and risk factors of Acute Angle Closure Glaucoma:
The cause of vision loss in all forms of glaucoma is optic nerve damage. There are many underlying causes and forms of glaucoma. Most causes of glaucoma are not known, but it is clear that a number of different processes are involved, and a malfunction in any one of them could cause glaucoma. For example, trauma to the eye could result in the angle becoming blocked, or, as a person ages, the lens becomes larger and may push the iris forward. The cause of optic nerve damage in normal-tension glaucoma is also unknown, but there is speculation that the optic nerves of these patients are susceptible to damage at lower pressures than what is usually considered to be abnormally high.
Sign and symptoms may include the following :
Treatment may include:
The objective of treatment is to reduce the intraocular pressure . Depending on the type of glaucoma, this is achieved by medications or by surgery. In Europe, Japan, and Canada laser treatment is often the first line of therapy. In the U.S., adoption of early laser has lagged, even though prospective, multi-centered, peer-reviewed studies, since the early ’90s, have shown laser to be at least as effective as topical medications in controlling intraocular pressure and preserving visual field.
