Glaucoma

GLAUCOMA is a slowly progressive disease of the eye, where in the pressure of   fluid within the eye gradually increases to a level not tolerated by the optic nerve. This leads to reduction in the field of vision and blindness, if left untreated.

People with positive family history of glaucoma are at a higher risk of getting this disease and therefore require ophthalmic evaluation. People over the age of 40 are likely to develop glaucoma though the disease may occur in people of all ages including new borns.

Increased pressure results from a buildup of excess fluid in the eye. Glaucoma is a dangerous eye condition because it frequently progresses without obvious symptoms. This is why it is frequently referred to as "the sneak thief of sight"

Glaucoma is a group of eye diseases that gradually steal sight without warning. In the early stages of the disease, there may be no symptoms. Experts estimate that half of the people affected by glaucoma may not know they have it.

Vision loss is caused by damage to the optic nerve. This nerve acts like an electric cable with over a million wires. It is responsible for carrying images from the eye to the brain.

There is no cure for glaucoma-yet. However, medication or surgery can slow or prevent further vision loss. The appropriate treatment depends upon the type of glaucoma among other factors. Early detection is vital to stopping the progress of the disease.

It was once thought that high pressure within the eye, also known as intraocular pressure or IOP, is the main cause of this optic nerve damage. Although IOP is clearly a risk factor, we now know that other factors must also be involved because even people with "normal" levels of pressure can experience vision loss from glaucoma.

Types of Glaucoma

There are several types of glaucoma, for example, congenital, primary, secondary, and normal tension glaucoma. Congenital glaucoma appears in young people; secondary glaucoma is the result of trauma, surgey or pre-existing eye diseases. There are two types of primary glaucoma most frequently associated with aging: acute or closed angle glaucoma, and chronic or open angle glaucoma.

Regardless of the type, glaucoma can impair vision by creating pressure that damages the optic nerve, The "cable" of nerve fibers that transmits messages about what we see from the eye to the brain.

It is important to recall the structure of the eye and how it works to understand the dangers posed by glaucoma. Glaucoma can cause damage when the aqueous humor, a fluid that inflates the front of the eye and circulates in a chamber called the anterior chamber , enters the eye but cannot drain properly from the eye. Elevated pressure inside the eye, in turn, can cause damage to the optic nerve or the blood vessels in the eye that nourish the optic nerve. The Human Eye, Its Functions, and Visual Impairment explains how the eye works. When glaucoma begins to affect a person's vision, the first problems are with peripheral vision, or what can be seen at the sides of the visual field, rather than in the center. If glaucoma progresses, it can destroy all peripheral vision, then impair central vision, and lead to total blindness. Treatments for glaucoma are aimed at bringing down the pressure in the eye to a level that is low enough to prevent harm to the optic nerve. Once the optic nerve is damaged from glaucoma, lowering the pressure in the eye only prevents further damage to the nerve. Damage already done to the optic nerve cannot be reversed.

How Common Is Glaucoma?

According to the Glaucoma Research Foundation glaucoma affects more than 3 million Americans. It is also reported that glaucoma is the third leading cause of legal blindness in Caucasians, and the leading cause of blindness in African Americans. Although anyone can get glaucoma, some people are at higher risk. Those at risk include:

• People over the age of 60
• African Americans over the age of 40
• People with a family history of glaucoma

Glaucoma Services at our Hospital has following facilities:

DIAGNOSTIC

1. Tonometry
2. Goldman Applanation Tonometer
3. Perkins' Applanation Tonometer
4. Tonopen
5. Gonioscopy
6. Slit lamps biomicroscopy with a Goldmann triple - mirror/ 90D/ 78D lenses
7. Special tests for Glaucoma
   • Humphrey visual field charting
   • Optic disc photography
   • Ultra sound biomicroscopy
   • Optical Coherence Topography OCT

When a person receives a diagnosis of glaucoma, it means a diagnosis of a life-long condition. However, early detection of glaucoma, appropriate and ongoing treatment, and the availability of specialized low vision and vision rehabilitation services if vision should become impaired, means that people who have glaucoma can live productive and satisfying lives.

A pressure check for glaucoma should be a routine part of every eye examination at least by the age of 35. A visual field test can also detect glaucoma by indicating the loss of peripheral vision.

TREATMENT

MEDICAL
It is the first line of treatment in open angle glaucoma. Periodic eye examination and response of appropriate anti-glaucoma drops is monitored. Add on therapy or change of medications done if a drug stops working.

LASER

• Midway/peripheral iridotomy in Angle Closure Glaucoma.
• Diode laser for Trans Scleral Cyclo Photocoagulation.

• Trabeculectomies with or without releasable sutures.
• Trabeculectomies with or without antimetabolites.
• Trabeculectomy with Extra capsular cataract extraction with intra ocular lens implantation or phaco emulisification with intraocular lens implantation.
• Bleb repairs.
• Specialized surgeries for glaucoma in children.