Although glaucoma is frequently associated with high pressure in the eye, loss of vision is caused by the subsequent damage at the optic nerve.
- The optic nerve connects the eye to the brain. All visual signals from the eye are sent to the brain through this nerve. It does not have the ability to heal or regenerate. Once the optic nerve has been damaged, loss of vision is permanent. The goal of glaucoma therapy is to prevent such damage.
- Ophthalmoloscopy is the technique used to examine the optic nerve. The nerve appears as a doughnut, with the center empty and the outer rim carrying the visual signals.
- As the intraocular pressure damages the optic nerve, the center of the doughnut becomes larger. The outer rim becomes thinner. The nerve tissue becomes compressed.
- In the late stages of the disease, the rim of the doughnut isd completely eroded away. The nerve tissue has died. Like a short in a wire, the nerve tissue loses its function. Visual signals no longer go from the eye to the brain and the visual field is compromised.
- The evaluation of the optic nerve is essential in the care of glaucoma, whether the patient has minimal or advanced disease.
- Photography can be used to highlight changes in the optic nerve and find the earliest signs of disease or progression. Computers can be used to assess optic nerve detail.
- The Glaucoma Center has the newest computerized methods of photography and assessment of the optic nerve.