Among the different types of glaucoma, the main ones are open-angle glaucoma and narrow-angle glaucoma. Both are characterized by an increase in intraocular pressure (IOP).
Open-angle glaucoma
Open-angle glaucoma is the most common form of glaucoma (about 80% of cases) and mainly affects the older population. It occurs when the aqueous humor (water-like liquid) reaches the iridocorneal angle inside the eye without being able to drain, causing an increase in ocular pressure and progressive damage to the optic nerve. However, open-angle glaucoma can develop with any value of ocular pressure because other risk factors also contribute to the pathology:
- heredity
- myopia
- thin cornea
- advanced age
- very low blood pressure
These factors can make the optic nerve particularly “weak” and cause it to suffer even with normal ocular pressures that are generally well tolerated.
Symptoms of open-angle glaucoma
This type of glaucoma progresses slowly and often without symptoms. The patient becomes aware of the visual problem only when the atrophy of the optic nerve is already advanced. For a timely diagnosis, it is very important to undergo periodic eye checks. The main risk factor for open-angle glaucoma remains the increase in intraocular pressure that compresses the fibers of the optic nerve and accelerates their loss with consequent damage to the visual field.
Therapies
In open-angle glaucoma, it is essential to intervene promptly. Undergoing regular eye checks is the key to protecting vision from the damage caused by glaucoma. To date, glaucoma therapy consists of reducing intraocular pressure. The reduction of intraocular pressure can be achieved through the use of medical therapy (eye drops or tablets), outpatient laser treatments or through surgery (there are different types of surgical interventions).
- Medical therapy
- Laser therapy
- Surgical therapy
Early treatment of open-angle glaucoma can slow the progression of the disease. Even if visual capacity cannot be recovered, further damage to the optic nerve and visual field should be prevented by lowering intraocular pressure.
Evolution of untreated glaucoma
The evolution of glaucoma not treated promptly is as follows:
- loss of peripheral (lateral)
- vision feeling of looking through a tunnel
- loss of vision.
Glaucoma can develop in one or both eyes even at different times.
Narrow-angle glaucoma
Narrow-angle glaucoma affects adults. The cause is the sudden closure of the drainage area of the aqueous humor which causes a rapid rise in eye pressure. If the rise is particularly high (as more frequently happens) it is called an acute glaucoma attack.
Symptoms of narrow-angle glaucoma
Narrow-angle glaucoma is symptomatic even in the initial phase of the disease. Early diagnosis makes it curable.
The symptoms, in case of rapid pressure increase, are as follows:
- severe pain in the eye
- nausea and vomiting
- redness of the eye
- headache
- vision of colored halos
- reduction of visual capacity.
If the increase in pressure is not high, the deep pain in the eye is mild and is associated with a temporary blurring of vision.