What is pigmentary glaucoma and how does it occur?

Pigment dispersion syndrome leads to pigmentary glaucoma

Pigmentary glaucoma is a form of glaucoma which is caused by pigment dispersion syndrome (PDS). PDS occurs when pigment granules (these make up the colour of your eye) flake off from the iris and end up in the clear fluid of your eye, known as the aqueous humor. There are a number of theories as to why PDS develops but one idea is that vigorous exercise can cause increased pigment release. Another suggestion is that your iris and lens touch so when you’re looking around and focusing your eyes on different text or objects, your iris rubs against the lens. This leads to some of the iris’s pigment flaking off before entering the aqueous humour. Mild dispersion of pigment, however, is a normal part of the ageing process, and is nothing to worry about as long as your eye pressure is healthy.

Experts estimate that around a third of patients who have PDS go on to develop pigmentary glaucoma. Glaucoma occurs due to the pigment in the aqueous humor clogging the eye’s drainage system, leading to a build-up of pressure inside the eye. Some people with PDS cope perfectly fine with additional pigment in their aqueous humor and it drains without issue. On the other hand, some people find that it causes their eye pressure to build significantly, leaving them at risk of pigmentary glaucoma. Interestingly, PDS affects men and women equally, but men are three times as likely as women to develop pigmentary glaucoma. Caucasian people are also at a greater risk of developing PDS. Further to this, 80% of people with PDS are myopic showing, quite clearly, that being short-sighted is a high risk factor for the condition.

Once your eye pressure is higher than it should be, and this is continued for an extended period, there is a risk of you experiencing optic nerve damage. Symptoms of optic nerve damage include blank spots appearing across your visual field, as well as loss of colour vision. This occurs when the optic nerve fibres die as a result of high eye pressure. Often, people notice that their peripheral vision is affected first by glaucoma however, by the time you have noticed it, it is too late to recover any lost vision.

What are the symptoms of pigment dispersion syndrome?

PDS is often symptomless and can only be diagnosed in a routine eye test. It leads to pigmentary glaucoma which is most often diagnosed in people aged in their 20s, 30s and 40s. This is significantly younger than other types of glaucoma develop and are diagnosed. Although PDS is often symptomless, if you do experience symptoms they can include:

• Blurry vision
• Halos when looking at bright lights
• Eye pain
• Corneal edema (swelling of the cornea)

If you experience these signs, or have symptoms of pigmentary glaucoma such as blank spots in your visual field, visit your optician for an eye test as soon as possible. There are treatment options available and, even if your vision hasn’t been negatively affected yet, regular monitoring is crucial in order to determine if and when you need treatment.

How can you treat pigment dispersion syndrome and pigmentary glaucoma?

If you have pigment dispersion syndrome which has been picked up during a routine eye test, and you’re experiencing no symptoms, you probably won’t need any medication or treatment yet. As we touched on briefly in the first paragraph, mild pigment dispersion is a normal part of the eye’s ageing process. It is only when your eye pressure rises and you begin to show signs of glaucoma that you need to act.

As vigorous exercise is a possible cause of pigment release, some patients with a large number of pigment deposits in their eyes are advised to avoid vigorous exercise where possible, or to take medication to lower their eye pressure before partaking in a hard workout. Medication to lower your eye pressure is one of the main treatment options for people with pigment dispersion syndrome, and this usually comes in the form of medicated eye drops.

In severe cases of PDS, or when your eye pressure becomes so high that it affects your optic nerve, you may be recommended laser treatment. This is a different type of laser surgery to what we offer at Optimax (which is designed to correct your vision) as for treating pigmentary glaucoma, the laser is used to make a small hole in your iris. This does not improve your vision, rather it helps to shift the anatomy of your eye so that there is less rubbing between the iris and lens, and therefore less pigment is released.

If you think you might have PDS or you’re worried about symptoms which could indicate glaucoma, visit your optician for a check-up. They will be able to advise on the best course of action for you and refer you for any necessary sight-saving treatment. You can read more about glaucoma on our website here to discover how high eye pressure can damage your vision.