Glaucoma is a group of eye disorders that cause damage to the optic nerve, optic nerve root and retina. The increased pressure in the eye cause the capillaries to collapse, resulting in damage to the retina and subsequent vision loss. The anterior chamber in the front of the eye contains a clear fluid that flows continuously in and out of the eye, nourishing the tissues inside the chamber. If the fluid does not flow out of the eye at the proper rate, pressure inside the eye increases, causing damage to the optic nerve and retina. Controlling and maintaining a healthy pressure is essential for healthy vision. Increased pressure is not the only reason people lose vision from glaucoma. Some have normal pressure but still lose vision as they require lower than normal pressure. The pressure needs to be lowered in order to the stop damage. In some cases, blockage causes an increase in pressure.
Intraocular Pressure and Glaucoma
Intraocular Pressure is the pressure created by the continual renewal of fluids within the eye. This pressure is increased in glaucoma. Normal intraocular pressure is between 13 and 20 mm Hg, the pressure that will not normally cause damage to the intraocular contents. In Medicine, pressure is still generally measured in millimeters of mercury. These measurements are given relative to current atmospheric pressure. Individual eyes respond to and require different pressures. Some can tolerate pressures that exceed 20 (ocular tension) and some will experience damage to the optic nerve with lower pressures (low-tension glaucoma).
Primary methods of occluding the outflow
The most common type of glaucoma is open-angle glaucoma. With this type the diameter of the openings of the trabecular meshwork becomes narrowed, increasing the resistance of fluid flow (the drain tube is suddenly reduced so pressure builds up.)
The pressure in the eye depends largely on the flow of aqueous humor into the eye, and how easily it leaves the eye. The rate at which fluid exits from the eye, or outflow, is the most important factor regulating pressure. Glaucoma usually results from a decrease in the facility of outflow. Increased pressure ultimately destroys the optic nerve cells causing blind spots in the field of vision, usually developing first in the peripheral, eventually affecting the central vision
Primary open-angle glaucoma (POAG) also called primary or chronic glaucoma affects approximately one percent of people over the age of fifty in the US. Open-angle means that the angle where the iris meets the cornea is as wide and open as it should be. It is the most common type of glaucoma.
In chronic glaucoma, there is a gradual imbalance between the production and removal (resorption) of the fluid in the back part of the eye (with supply exceeding demand). The pressure builds causing intraocular pressure, but there is generally no swelling on the cornea, with no visible abnormality of the trabecular meshwork. Because the patient experiences no symptoms, it often goes undetected. However, vision impairment occurs.
In open-angle glaucoma the diameter of the openings of the trabecular meshwork becomes narrowed, increasing the resistance of fluid flow. (the drain tube is suddenly reduced so pressure builds up.) The trabecular meshwork is an area of tissue in the eye located around the base of the cornea, near the ciliary body and is responsible for draining the aqueous humor from the eye by way of the anterior chamber (the chamber on the front of the eye covered by the cornea).
In acute angle-closure glaucoma, a less common form of glaucoma, the intraocular pressure rises because the canal into which the fluid in the front part of the eye normally drains is suddenly blocked. The angle between the iris and cornea has a closed or narrow angle. It develops very quickly and has symptoms and damage that are usually very noticeable in a short period of time. This demands immediate medical attention.The usual symptoms are sudden eye pain, a red eye and reduced vision. Immediate treatment is needed to relieve symptoms and to prevent permanent loss of vision.
Acute angle-closure glaucoma is also called acute glaucoma or narrow-angle glaucoma. Unlike open-angle glaucoma, angle-closure glaucoma is a result of the angle between the iris and cornea closing.
Normal-Tension Glaucoma (NTG) is called low-tension or normal-pressure glaucoma. In normal-tension glaucoma the optic nerve is damaged even though they have almost normal pressure levels.
Congenital glaucoma occurs in babies when there is incorrect or incomplete development of the eye’s drainage canals during the prenatal period. This is a rare condition that may be inherited. When uncomplicated, microsurgery can often correct the structural defects. Other cases are treated with medication and surgery.
With secondary glaucoma the trabecular meshwork becomes blocked. Various types of debris or scar tissue may cover the meshwork.
Arkansas Acupuncture Center’s acupuncture treatment, called micro acupuncture for glaucoma and other vision disorders helps patients by restoring normal blood flow to the retina and optic nerve so that the eye can begin to heal. Healing allows for more normal cellular repair, or cell regeneration. It will not necessarily reduce pressure so it is essential for patients to continue with their conventional treatment regimen for maintaining normal pressure in the eye. The conventional treatment consists of prescription eye drops or oral medication to control pressure. The acupuncture treatments, or microacupuncture, we perform her at the Arkansas Acupuncture Center for glaucoma are similar to the acupuncture treatments for macular degeneration, as well as the acupuncture for retinitis pigmentosa. About a third of the patients coming to the Arkansas Aupuncture Center for eye diseases are receiving acupuncture for glaucoma.
Glaucoma patients if you are to receive a visual field scan, do not use drops that morning until after the scan. Call us if you have questions.