Pigment Dispersion Syndrome

Pigment Dispersion Syndrome occurs only in certain people – generally white nearsighted males between 20-50...

Think of your iris – the coloured part of your eye – as being painted on. Now imagine something constantly rubbing against it. As time passes the paint eventually starts to flake and chip off because of friction. This is basically what happens when you have pigment dispersion syndrome (PDS) except the flaking is actually the pigment that colours your eye.

The flaking off of pigment granules occurs as a result of the proximity between the iris pigment layer and surrounding zonular fibres of the eye. It occurs only in certain people – generally white nearsighted males between 20-50 – and leads to a disruption of the iris surface. Sometimes exercise activity can cause the shedding of pigment. Granules that normally adhere to the back of the iris begin to come off and blend into the flow of aqueous humor (the fluid in our eyes). These granules are like debris in floodwater and are quite dangerous in terms of blockage. In the human eye the trabecular meshwork is a network of fibres responsible for the continual drainage of the aqueous humor from the eye. The pigment granules flow along with the aqueous humor toward the meshwork and can lodge there blocking the outflow of fluid. The end result of this is increased intraocular pressure which can lead to visual loss and glaucoma.

PDS is generally asymptomatic and is often discovered upon routine examination. On its own this syndrome has no ill effects on ocular health or vision other than the potential for developing consequent glaucoma. In about one third of cases of PDS pigmentary glaucoma results. Unlike open-angle glaucoma pigment glaucoma has a quick onset and quite rapid progression. Some patients may experience the following symptoms:

• a feeling of increased pressure in the eye
• coloured halos around lights
• blurred vision
• subtle pain

If any of these symptoms are severe – your eye doctor should be contacted immediately. As soon as diagnosis is evident prompt aggressive therapy is essential.

Only your eye care practitioner can diagnose pigment dispersion and since the potential for glaucoma is elevated routine eye assessments should be scheduled. This way you can be monitored for increased eye pressure or other abnormalities before any long-lasting vision damage can occur.