Glaucoma Treatments

Glaucoma is the name for a group of diseases of the eye where the optic nerve, which connects the eye to the brain, becomes damaged.

There are three main types of glaucoma. These are primary, secondary and developmental (glaucoma in babies and children).

It is quite a serious condition that has no obvious symptoms in its early stages, and can be characterised by pressure building up inside the eye which then leads to the damage to the optic nerve. The optic nerve is used to transfer visual information to the brain, and any damage to the nerve fibres will not recover.

If glaucoma is not treated it can lead to sight loss, or even blindness neither of which are reversible. It is essential to keep up to date with regular eye tests, as this is the way to detect that you are suffering from glaucoma. Early intervention is vital along with careful monitoring to ensure that any damage does not result in permanent loss of vision.

Glaucoma Older Lady Having Test

How could my Eyes be Affected by Glaucoma?

It is important to understand a little about the structure of the eye to appreciate the effects of glaucoma.

Aqueous humour, which is a clear fluid, flows through your eye. It maintains the shape of the eye so that it can function properly and does this by keeping the correct amount of pressure inside your eye. This pressure is called intraocular pressure.

High pressure in the eye is called ocular hypertension. The damage to the optic nerve is usually caused when the intraocular pressure becomes excessively high, killing the nerve fibres.

Not all patients who suffer from ocular hypertension will develop optical nerve damage, but they do need to be monitored carefully for signs of glaucoma so that preventative treatment can be given if required.

Damage to the  optic nerve can also occur when the intraocular pressure is normal. This condition is called normal tension (or low tension) glaucoma.

Understanding the structure of the eye

The part labelled the ciliary body is where the aqueous humour (the fluid within the eye) is made.

Between the iris and the cornea is the so-called ‘drainage angle’ of the eye. The aqueous flows down behind the lens and under the iris, then through the pupil and drains out through the drainage angle. The intraocular pressure is a balance between the production of fluid in the eye and the drainage out of the eye.

When the drainage out of the eye is restricted the balance becomes uneven and the pressure in the eye will rise.

What types of glaucoma are there?

To understand the different types of glaucoma, it is useful to know how drainage occurs in the eye.

As you can see in the section labelled ‘How could my eyes be affected by glaucoma?’ your eye pressure is controlled by watery fluid called aqueous humour. It is made in the ciliary body, flows through the pupil and drains away through tiny channels called the trabecular meshwork in the angle between the cornea and the iris (the drainage angle). If the balance between the inward flow and the outward flow is disrupted this can cause the eye pressure to rise.

Primary Open Angle Glaucoma (POAG)

Most cases of POAG are caused by the drainage of the fluid out of the eye not functioning as well as it ought to. When the fluid in the eye can not escape as quickly as it is made it will build up in the eye causing the pressure in the eye to rise. The tiny blood vessels that supply the optic nerve cannot supply sufficient blood when this pressure is increased, and in addition the raised pressure can press onto the nerve itself. Both of these factors can damage the optic nerve.

Ocular hypertension causes the pressure in the eye to be raised, but without causing damage to the optic nerve, and no deterioration in vision.

Patients with this condition have an increased risk of glaucoma, and may need to be treated to reduce their risk, and so that they can be treated as soon as any glaucoma develops.

With secondary glaucoma, the raised intraocular pressure will have been caused by (i.e. be secondary to) a different underlying medical condition which has led to the drainage from the eye failing. These conditions may be a trauma to the eye, neovascular glaucoma (a side effect of conditions such as diabetic eye disease), or previous surgery.

Damage to the optic nerve can occur, which means that the original cause will need to be treated, along with the glaucoma itself.

This condition is very rare and can occur when the pressure in the eye becomes raised due to developmental abnormalities in the eye.

PACG occurs when the fluid in the eye cannot escape properly because the ‘drainage angle’ is too narrow which reduces the effectiveness of the draining function. Some people’s eyes naturally have narrow drainage angles. They may have smaller eyes, be long sighted or be of particular ethnic origins.

This narrower angle can slow down drainage, or even close completely causing fluid to build up and eye pressure to rise.

PACG can be chronic or acute.

Chronic PACG will develop slowly as the drainage angle diminishes slowly, which causes a gradual rise in pressure (this does not normally have symptoms). The resultant rise in eye pressure occurs slowly. Chronic PACG will normally be spotted at a routine eye test appointment.

Acute PACG occurs when the drainage route closes suddenly and completely. This is also known as acute angle closure crisis. Acute PACG normally only affects one eye and will cause redness and pain around and in the eye, along with a rapid deterioration in vision and can be extremely painful.

Who is at Risk of Glaucoma?

Primary Open Angle Glaucoma (POAG) is uncommon in people under forty. Around two people in one hundred over the age of forty will develop POAG, while this will rise to more than one in twenty people who are aged eighty or more.

It is very important that you inform any close blood relatives if you develop glaucoma. The reason is that anybody who has a close relative with glaucoma has four times the likelihood of developing it themselves.

Anybody who has a close relative with glaucoma needs to be aware of this risk so that they can be tested.

People with short sight (myopia) have an increased risk of developing glaucoma.

People with long sight are at increased risk of developing Primary Angle Closure Glaucoma (PACG).

Primary Open Angle Glaucoma (POAG) is four times more common in people of African-Caribbean origin than in people of European origin, and people of east Asian origin also carry an increased risk of developing the condition.

How is Glaucoma Diagnosed?

In most cases the early signs of glaucoma are detected during a routine eye test with an optometrist.

It is very important that you have your eyes tested every two years because conditions like glaucoma, diabetes, high cholesterol and macular degeneration can all be spotted at these consultations.

This is even more important to remember if you are Asian, African-Carribean, have low blood pressure, are diabetic or short sighted because this could mean that you have a higher risk of developing glaucoma.

If the optometrist identifies that you may have glaucoma you will be referred to a specialist glaucoma service. If you are referred for further consultation this does not mean that you definitely have glaucoma and it does not mean that you will lose your sight, only that you may be at increased risk.

We may use several different tests to determine whether you have glaucoma.

We use this test to determine whether you have gaps in your peripheral vision (that is the vision away from the centre, or everything you’re not looking directly at) and can identify the specific area of sight loss.

We will ask you to look into a machine and press a button every time you see a dot of light. If you have glaucoma, there may be some gaps in your field of vision meaning that you may miss some of the flashing lights.

We will use Goldman Applanation Tonometry to measure the intraocular pressure of your eye. This is not the same test as the air puff that you might have had at the optometrist.

A slit lamp allows detailed examination of your eye with special attention to the optic nerve.

This is a painless examination that will allow us to check the ‘drainage angle’ of your eye where aqueous humor naturally drains out of your eye.

This is a painless test for measuring the thickness of your cornea.

It is really important to get an accurate measurement of cornea thickness because if your cornea is thicker than average then your intraocular pressure might be overestimated, but if it is thinner than average the reverse could be true leading to the pressure reading being underestimated.

This is a painless procedure. We will examine the back of your eye and may take a photograph to check the health of the optic nerve.

This test will measure the thickness of the nerve fibre layer of the optic nerve and nerve fibre loss can be detected.

What Treatments are Available for Glaucoma?

  • Eye drops

    Many different eye drops are available for the treatment of glaucoma, and they all work in different ways to reduce the intraocular pressure of your eye by reducing the amount of fluid in your eye. This in turn leads to reduced damage to the optic nerve.

  • YAG Selective Laser Trabeculoplasty (SLT)

    In the healthy eye, the fluid called aqueous humour flows freely into the front of your eye through the pupil then drains away through channels called the trabecular meshwork. In some cases these drainage channels do not work properly, and your eye pressure increases.

    We use YAG selective laser trabeculoplasty (SLT) to apply a laser beam to the drainage channels, which helps to unblock them. The fluid in your eye can then flow through the channels more easily, which reduces the pressure in your eye.

  • Trabeculectomy Surgery

    A trabeculectomy is an eye operation that will improve the drainage of fluid out of the eye. This is achieved by creating a small blister (called a bleb) under the surface of the eye, which acts as a trap door to allow extra fluid to pass out of the eye, improving the drainage of the eye and in turn reducing the intraocular pressure and protecting the optic nerve.

  • YAG Laser Peripheral Iridotomy

    If you have angle closure this means that the coloured part of the eye, the iris, can move forward and obstruct the drainage channels. When this happens the fluid can not escape from the eye and your intraocular pressure increases.

    We use YAG laser peripheral iridotomy to create a small hole in your iris to form a permanent small passage which allows the excess fluid to escape. The laser is used to push the iris tissue backward to unblock the drainage channels.

  • Aqueous shunt implantation

    An aqueous shunt is a device which is implanted into the eye. The shunt comprises two parts, the first is a small tube made from silicon, and the second is a plate that sits in the surface of the eye. The extra fluid in the eye can then drain away through the tube to a small blister (called a bleb) under the surface of the eye and drain away. This improves the drainage of the eye and in turn reduces the intraocular pressure and protects the optic nerve.

    An aqueous shunt is also referred to as tube implant, glaucoma drainage implant or glaucoma tube shunt.

  • MIGS

    Minimally invasive glaucoma surgery, or MIGS encompasses a range of techniques, implants and devices which all work to lower the intraocular pressure in the eye by increasing the drainage of the eye and thus protect the optic nerve.

    The reason these procedures are called “Minimally invasive” is that very tiny incisions and/or microscopic equipment is used. This has been designed to minimise risk as compared to other treatments such as trabeculectomy or aqueous shunt.

  • iStent Drainage Implant Surgery

    In the healthy eye, the fluid called aqueous humour flows freely into the front of your eye through the pupil then drains away through channels called the trabecular meshwork.

    In some cases these drainage channels are partially blocked and your eye pressure increases.

    We use iStent drainage implant surgery to provide additional drainage and reduce pressure inside the eye.

    The iStent is a microscopic, one millimeter long, non-magnetic titanium tube, which is inserted into the drainage channel in the eye. This procedure is most commonly undertaken in conjunction with cataract surgery, but it can also be used as a stand-alone procedure.

Book An Appointment

Choose File
Thank you for your message. It has been sent.
There was an error trying to send your message. Please try again later.

Contact Info