What is glaucoma?
Glaucoma is a collective term used to describe a number of different diseases, caused by changes in the optic nerve. The changes will usually result in a narrowing of the visual field – the so-called ‘tunnel vision’, but in rare instances, it can also cause total blindness. Glaucoma is divided into acute and chronic glaucoma.
Acute glaucoma is a sudden increase of the eye pressure. It can usually be seen in people with small and far-sighted eyes, and here, a fast-acting treatment is especially important as the condition can result in blindness in a matter of days. Chronic glaucoma is the most common type of glaucoma, and as the disease is symptom free for the first many years, it is often diagnosed ‘by accident’ by an eye specialist. Here, the specialist will observe a bleached optical nerve and potentially an issue with the visual field. An important risk factor is elevated eye pressure.
What are the symptoms of glaucoma?
Acute glaucoma is associated with sudden symptoms, herein:
Nausea and vomiting
Seeing rainbow coloured rings
Chronic glaucoma cause no noticeable symptoms during the initial many years. Later, the increased eye pressure can result in symptoms, such as:
Blushing of the mucus membrane of the eye
Grey, ‘moth-eaten-like’ patches in the vision field
What are the causes of glaucoma?
In the front of the eye, there is a watery fluid referred to as the ‘aqueous humour’. The aqueous humour is produced by the ciliary body, and it is an important element for moisturizing the eye. There is a constant production of aqueous humour, and thus, it is important that a corresponding amount of fluid is constantly removed. The aqueous humour runs out of the eye through the anterior chamber angle.
Acute glaucoma is the result of a blocking of the chamber angle, causing aqueous humour fluid to build up in the eye. This causes the eye pressure to increase. An increase in eye pressure will destroy the nerve cells, which intercepts the visual impression and sends signals to the brain via the optical nerve. Frequently, the reason for this blocking of the chamber angle is that the muscle that expands the pupil is overactive. This muscle is particularly active when you are in the dark. Therefore, glaucoma almost always occurs in dark surroundings.
The cause of the chronic form of glaucoma is unknown, but many elements point towards the reason being a poor blood circulation locally near the optical nerve. It is known that several factors contribute to an increased risk of developing glaucoma and these factors include: hereditary disposition, age, definite myopia, eye injuries, iritis, elevated blood pressure and long-term treatment with adrenocortical hormone.
What are the treatments for glaucoma?
Acute glaucoma is treated at the eye specialist’s office. Here, glaucoma patients will receive eye drops that cause the pupil to contract. This contraction of the pupil enables the drainage of fluid to be re-established and the eye pressure to drop, thereby reducing the damage to the optical nerve. When the pressure is stable, it may be necessary to have surgical treatment or laser treatment that makes a hole in the iritis upwards, which allows for an improved drainage of the aqueous humour fluid.
Chronic glaucoma can be treated in different ways. Medical treatment consists of eye drops which either reduce the production of fluid or increase the drainage from the eye. Laser treatment can increase the drainage by making small holes in the chamber angle, and this treatment is usually offered if the eye drops do not have the desired effect. As a last resort, surgery can be used as it can create an artificial drainage for the fluid under the conjunctiva of the eye. This treatment can prevent the condition from worsening, but it cannot improve the vision.