What is glaucoma?

A number of conditions can lead to raised pressure
within the eye which if left untreated can cause
irreversible damage.

What causes glaucoma?

The factors that cause glaucoma are not fully known. However, in many cases the pressure in the eye is thought to be responsible, at least in part, for the damage caused. The pressure in the eye is usually higher than the normal range but in some cases it is within the normal range but is considered to be too high for the individual eye. Other factors sometimes include alterations in the bloodflow to the optic nerve head (the front part of the optic nerve), changes in the tissues supporting the optic nervehead, and genetic factors.

Who gets glaucoma?

Primary open angle glaucoma is the commonest type of glaucoma and affects 1-2% of the population. the risk increases with age and is less common in caucasians. Risk also increases if a family member is affected. Use of steroids may cause a rise in intraocular pressure and hence glaucoma.

What symptoms are associated with glaucoma?

Most patients are unaware of their condition as there maybe no obvious symptoms. It is usually discovered by routine testing at the opticians. For most patients the main problem is loss of field of vision which means peripheral vision narrows. Sharpness of vision tends to be affected later on, although localised areas of loss of central vision can occur. "Tunnel vision" is only seen in advanced disease. One important aspect is that it may affect your vision to the level that you fail the legal requirements to drive. You should inform the DVLA and your insurers if you have this condition. Many people however will still meet the legal visual requirements for driving.

Which tests may be helpful?

A complete eye examination, with measurement of the intraocular pressure, an examination of the drainage angle (gonioscopy) and optic disc, and an assessment of the visual field.The tests are usually repeated for monitoring at regular intervals.

Can glaucoma be treated?

This is usually done in stages depending on the success of initial treatments

  * Medical—eye drops to reduce the intraocular pressure
  * Laser—a laser trabeculoplasty, to reduce the intraocular pressure
  * Surgery—a trabeculectomy, to reduce the intraocular pressure

In the majority of cases the progression of the visual loss can be halted or greatly reduced. However, despite good intraocular pressure control a minority of cases can still show progressive changes.

How vision may appear with glaucoma