Glaucoma: cause, symptoms, treatment

Glaucoma is a chronic disease of the eye that slowly damages the optic nerve. In many cases, increased intraocular pressure plays a role. If left untreated, glaucoma can lead to blindness, but is often easily treatable if diagnosed early.

Cataracts cause the lens of the eye to cloud: vision becomes blurred. However, cataracts can usually be operated on without any problems. Glaucoma, on the other hand, affects the optic nerve and can’t be cured. “Glaucoma is the second most common cause of blindness in industrialised countries,” says Dr Fabian Gielen, ophthalmologist at Winterthur Cantonal Hospital. “However, if detected in time, those affected can lead a completely normal life.”

A distinction is made between primary glaucoma, which occurs independently, and secondary glaucoma, which can occur as a result of an existing disease, a medical procedure, an injury or as a side effect of medication.

Most glaucomas can also be divided into two categories: open-angle glaucoma, where the drain of the eye is wide open, and closed-angle glaucoma, where the drain of the eye is partially or fully obstructed. According to Gielen, genetic factors often also play a role: “Glaucoma can run in families as well as be caused by other eye diseases.”

The disease usually develops gradually. The outflow of aqueous humour is often impaired, leading to increased intraocular pressure. One of the jobs of the aqueous humour is to supply the lens and cornea with nutrients. Normally, as much new aqueous humour is produced as is removed. If it can’t drain away or if too much new fluid is produced, the intraocular pressure rises.

As a result, the optic nerve is increasingly compressed and irreparably damaged. However, there is no clear explanation as to why some people develop glaucoma and others don’t.

Normal intraocular pressure is between 10 and 21 mmHg. But according to Gielen, this is no guarantee: “Normal pressure doesn’t rule out glaucoma – and increased pressure doesn’t necessarily mean that you will develop the disease.” Unlike blood pressure, intraocular pressure can’t be consciously influenced. That’s why measurement by an ophthalmologist is crucial.

The risk of glaucoma increases with age: “The probability of developing glaucoma doubles every ten years,” says Gielen. Glaucoma is one of the main causes of blindness in people over 60 in Switzerland.

From the age of 40, Gielen therefore recommends regular check-ups, especially for the following risk factors:

• Family history
• Severe short-sightedness or long-sightedness
• Other eye diseases

Women are affected more often than men. It isn’t yet known why. Another interesting finding is that yoga exercises with inverted poses have caused glaucoma in some people, as it temporarily increase the pressure on the eyes. “But that’s rare,” says Gielen.

Glaucoma is particularly insidious because it goes without symptoms for a long time. “By the time symptoms appear, the damage is usually already advanced,” explains Gielen. Possible signs include:

• Blind spots in the field of vision
• Problems with vision in dim light
• Blurred vision
• In acute cases: Eye pain, nausea, sudden loss of vision

Glaucoma can’t be prevented directly – but it can be detected early. Gielen therefore recommends regular ophthalmologic check-ups from the age of 40. This includes:

• Eye pressure measurement
• Assessment of the optic nerve
• Visual field examination, if necessary

“If the disease is diagnosed early, its progression can be slowed significantly,” says Gielen. He recommends that everyone over the of 40 should see an ophthalmologist for an examination. If there are no signs of glaucoma, a check-up every few years is sufficient. If an issue is detected, action can be taken at an early stage. The doctor responsible will assess each case individually and take the necessary steps.

Many people prefer gentle methods and self-help. However, glaucoma can’t be actively self-treated or prevented. A healthy lifestyle minimises the risks, i.e. no nicotine, alcohol or drugs. “Unfortunately, there’s not much you can do yourself,” says Gielen. That’s why preventive care is all the more important.

The aim of any treatment is to lower the intraocular pressure in order to relieve the optic nerve and stop the progression of the disease. The appropriate therapy depends on the stage of the disease and is prescribed on a case-by-case basis.