Glaucoma is a group of diseases of the optic nerve. The optic nerve carries information from the eye’s retina to the brain. When the optic nerve has been damaged by glaucoma, it results in loss of peripheral vision (the vision on the sides).
Open Angle Glaucoma
- Open angle glaucoma is the most common type of glaucoma. It is diagnosed when progressive damage to the optic nerve or peripheral vision is observed.
- The eye has its own intraocular pressure. The pressure fluctuates throughout the day. Lowering the intraocular pressure from baseline helps prevent further damage to the optic nerve and vision.
- Treatment to lower the intraocular pressure include selective laser trabeculoplasty (SLT), glaucoma eyedrops, and surgery. Exercise, a healthy diet, and good general health also help.
- In some cases, surgery is needed to lower the intraocular pressure.
- Office visits are needed every few months to ensure the glaucoma is under control. Exams will include visual field tests and scans of the optic nerve.
- The shape of the optic nerve looks like glaucoma, but the peripheral vision is normal.
- Some people are born with optic nerves that look suspicious for glaucoma.
- Glaucoma suspects need exams every 6 to 12 months to look for changes consistent with glaucoma.
- Some patients remain glaucoma suspects for their entire life and never develop glaucoma.
- The intraocular pressure is elevated, but the optic nerves may be healthy. Some patients will eventually develop glaucoma. Having thick corneas lowers the risk of developing glaucoma.
Narrow Angle Glaucoma
- Inside the eye, fluid is continuously produced by the tissue under the iris. The fluid exits the eye through the angle (see the diagram above).
- In some eyes, the angle is narrow. This puts the eye at risk for an acute angle closure glaucoma attack. When the angle completely closes, the eye fluid has nowhere to drain. This causes a sudden rise in the intraocular pressure of the eye and requires emergency treatment.
- An iridotomy is a procedure that uses a laser to make a tiny opening in the iris (colored part of the eye). The opening acts as a safety drain and can prevent an angle closure attack. Laser iridotomies are recommended for eyes with narrow angles.
- Some medications (like Sudafed) have warnings to avoid use if you have glaucoma. These warnings are only intended for patients with narrow angles that have not had laser iridotomies. They do not apply to patients with open angles.
Other Types of Glaucoma
- Less common types of glaucoma include pigmentary glaucoma, exfoliative glaucoma, uveitic glaucoma, and steroid induced glaucoma.