Glaucoma is a group of diseases that can damage the eye's optic nerve and result in vision loss and blindness. Most studies show that at least half of all people with glaucoma do not know that they have it. Damage from glaucoma cannot be reversed. Glaucoma has no warning signs, and if left untreated, it can cause permanent vision loss. That’s why early detection and treatment are so important.
Glaucoma is a group of diseases of the optic nerve - the part of the eye that carries the images we see to the brain. The optic nerve is made up of many nerve fibers. Damage to the optic nerve can occur when the pressure in the eye gets too high. The level of pressure within the eye is determined by a balance between aqueous fluid being pumped into the eye and fluid leaving through the filtering system.
Aqueous is a watery liquid filtered from blood which is pumped into the eye. It circulates around the lens and through the pupil to reach the filtering system, or meshwork. It exits through pores in the meshwork to collect in the canal and then return to the bloodstream.
If the drainage angle is blocked, excess fluid cannot flow out of the eye, causing the fluid pressure to increase. When pressure increases the optic nerve fibers are damaged.
Causes of raised pressure:
- Open Angle: (most common) Increased resistance to outflow by the pores of the filtering system. The risk of developing chronic open angle increases with age. The drainage angle of the eye becomes less efficient over time, and pressure within the eye gradually increases causing damage to the optic nerve.
- Closed Angle: (less common) Angle closure where the iris blocks access to the filtering system. In these eyes, often small and farsighted, the iris can be pushed forward, blocking the drainage channel completely. Since the fluid cannot exit the eye, pressure inside the eye builds rapidly and causes an acute attack.
When damage to the optic nerve fibers occurs, blind spots develop. These blind spots usually go undetected until the optic nerve is significantly damaged. If all the optic nerve fibers die, blindness results.
Risk Factors for Glaucoma:
- Age: 40 and older
- Family history of glaucoma
- African or Hispanic ancestry
- Farsightedness or nearsightedness
- Past eye injuries
- Thin central corneal thickness
- Systemic health problems (diabetes, migraines, poor circulation)
- Pre-existing thinning of the optic nerve
Early detection and treatment by Dr. Robinson is key to preventing optic nerve damage and vision loss from glaucoma. Damage caused by glaucoma cannot be reversed. Eye drops, laser treatment and surgery are used to lower eye pressure and help prevent continued damage.
A commonly used laser treatment for glaucoma which Dr. Robinson performs in his office is called Selective Laser Trabeculoplasty (SLT). It safely and effectively reduces intraocular pressure. This procedure can be used as an adjunct or primary treatment for glaucoma. Dr. Robinson will discuss treatment options with you during your visit.
If you have glaucoma or are a suspect for glaucoma, the extent of the disease will need to be determined by further in-office testing that may include visual field, optic nerve tomography, corneal thickness measurement, etc.