Anatomical Narrow Angles
The angle of the eye is defined as the angle that is formed between the cornea (the clear, outer portion of the front part of the eye) and the iris (the colored part of the eye). The angle is where the draining apparatus of the eye eye is located. When the anterior chamber angle is narrow, the drainage system is at risk for becoming so narrow that fluid can no longer escape. This could result in acute and chronic angle closure glaucoma.
There are often no symptoms associated with anatomically narrow angles. While patients with anatomic narrow angles have a predisposition to develop glaucoma if left untreated, they often do not have any evidence of glaucoma itself and require no long-term glaucoma treatment. To prevent further narrowing of the angle and thus to prevent acute and chronic angle closure glaucoma, a Laser Peripheral Iridotomy is needed.
Laser Peripheral Iridotomy
When the passageway to the drains of the eye becomes narrow, among the first steps in preventing it from closing completely is placement of a laser peripheral iridotomy (LPI). The LPI can be thought of as a trap door that can be used to allow fluid to escape in the event that the angle closes off and the pressure in the eye begins to rise. In this procedure, laser energy is used to make a tiny hole in the iris. This hole helps alter anatomy inside the eye to maintain a more open passageway to normalize intraocular pressure in the event it should increase.
Open Angle Glaucoma Treatment
This form of glaucoma is more common in Western cultures and can be divided into several different types. Typically a chronic condition that develops in older people, primary open-angle glaucoma is the most common form of glaucoma. The draining angle between the cornea and the iris is open but it does not drain adequately, allowing pressure to build up in the eye. The symptoms of primary open angle glaucoma often go unnoticed until the central vision is affected.
Other forms of open angle glaucoma include normal tension or low tension, congenital, secondary, pigmentary and exfoliative glaucoma. In each of these types, the angle is anatomically open, but the eye pressure remains too high.
Treatment for open angle glaucoma may include eye drops, oral medication or surgery. The goal is to reduce the pressure in the eye to avoid nerve damage.
Narrow Angle Glaucoma Treatment
Narrow angle glaucoma can be a more severe condition than open angle. If the angles of the eye are already small, a closure can occur suddenly and without warning. The pressure in the eye can increase rapidly in narrow angle glaucoma, causing nerve damage before it can be treated.