Glaucoma is a group of eye diseases causing optic nerve damage. The optic nerve carries images from the retina, which is the specialized light sensing tissue, to the brain so we can see. In glaucoma, eye pressure plays a role in damaging the delicate nerve fibres of the optic nerve. When a significant number of nerve fibres are damaged, blind spots develop in the field of vision. Once nerve damage and visual loss occur, it is permanent.
Most people don't notice these blind areas until much of the optic nerve damage has already occurred. If the entire nerve is destroyed, blindness results.
Different Types of Glaucoma
Chronic open-angle glaucoma is the most common form of glaucoma. The "open" drainage angle of the eye can become blocked leading to gradual increased eye pressure. If this increased pressure results in optic nerve damage, it is known as chronic open-angle glaucoma. The optic nerve damage and vision loss usually occurs so gradually and painlessly that you are not aware of trouble until the optic nerve is already badly damaged.
Angle-closure glaucoma results when the drainage angle of the eye narrows and becomes completely blocked. In the eye, the iris may close off the drainage angle and cause a dangerously high eye pressure.
Not all types of glaucoma are characterized by eye pressures. In normal-tension or low-tension glaucoma, the optic nerve suffers damage with the resulting visual field loss even though normal eye pressures are maintained. Eyes afflicted with this condition are far more susceptible to optic nerve damage with any increase in the intraocular pressure compared to other eyes.
The signs and symptoms of primary open angle glaucoma and acute angle-closure glaucoma are quite different.
Signs and symptoms of primary open-angle glaucoma
- Peripheral vision is gradually lost. This nearly always affects both eyes.
- In advanced stages, the patient has tunnel vision
Signs and symptoms of closed angle glaucoma
- Eye pain, usually severe
- Blurred vision
- Eye pain is often accompanied by nausea, and sometimes vomiting
- Lights appear to have extra halo-like glows around them
- Red eyes
- Sudden, unexpected vision problems, especially when lighting is poor
Find out more about our visual aids if you have Glaucoma
Many people who lose their peripheral vision can benefit from a video magnifier. Because of the loss of peripheral vision, a large screen does not necessarily provide extra benefit. Often a small screen can be the most helpful. Therefore, handheld video magnifiers are often recommended.
RUBY Handheld Video Magnifiers, Looky Portable Video Magnifiers and the Optelec Compact Magnifiers (only available in certain countries) can slip comfortably into a pocket or purse, giving you easy access to photos, letters, menus, prescription labels, and so much more, wherever you go.
There are many devices that can assist you in a variety of daily tasks if you have Glaucoma.In addition to the handheld video magnifiers, below is a list of other devices that may be useful:
- TOPAZ Desktop Video Magnifiers allow you to read magazines and letters, view family photos, write checks, or engage in your favourite hobby, all in the comfort of your home or office.
- Blaze ET and Blaze EZ
- Large Print Keyboards (Zoomtext and Keys-U-See Large Print Keyboards)
The information provided on this site is intended for your general knowledge only and is not a substitute for professional medical advice.