Top 5 eyesight threats : 1 of 5

What comes before death and taxes ?

There are so many things out there to “get you” and one day, one of them will succeed. But you hope it will be very old age. It may feel like there is not a lot you can do about it. However if you take some sensible precautions, it can make a big difference to ensuring you extend the quality of your life.

Mary Browne – Optometrist will tell us about the top five threats to your eyesight over the next few months.  Normally our blogs are short, but these will go into a little more depth for those interested in the topics.

The principle messages are :

1. Have a regular eye examination, particularly when you hit 40 years of age.

2. Find and stick with an optician that you are going to have a relationship with over a long period of time.

3. Sight loss is far more common than you think, and it has a devastating impact  upon your independence and quality of life if it fails significantly.

This series is courtesy of Mary Browne. Mary is our resident optometrist of many years experience at our Rathmines practice.  Mary explains what’s happens in a non technical manner as much as possible.

The eye is hollow on the inside, and filled with gel.  The gel is produced and drained away all the time.  If the gel isn’t draining away as quickly as it’s being produced, it can start to build up inside the eye.  This causes extra pressure in the eyeball, which can lead to nerve damage.


This nerve damage usually occurs from the outside in, meaning that you lose your peripheral vision first.  This can easily go unnoticed until the vision loss is quite advanced.  This is why it is very important to have regular eye tests to aid in early detection of glaucoma, in order to prevent further vision loss.



Ways of detecting glaucoma

  1. Assessment of the optic nerve at the back of the eye
  2. Photography of the inner eye for comparison at future visits
  3. Measuring the IOP (eye pressure)
  4. Visual Fields testing (to check for loss of peripheral vision)


Types of Glaucoma

1. Primary Open Angle Glaucoma

      • Most Common Form
      • Opening to drainage system is open, but there is a blockage within the drainage system that prevents fluid draining easily
      • No symptoms until significant amount of vision is lost

2. Angle Closure Glaucoma

      • Much less common than primary open angle
      • Opening to the drainage system is narrow or closed completely
      • Symptoms include eye pain, headache, haloes around lights and blurred vision.
      • The pupil of the affected eye may be dilated.


3. Normal Tension glaucoma

      • Optic Nerve damage even though pressures are within normal ranges
      • Treated in same way, but need to get pressures even lower than other glaucoma types, in order to prevent further damage


4. Secondary Glaucomas

      • Can occur due to complications of other conditions such as eye trauma, cataracts, eye surgery, or tumours

Risk Factors for Glaucoma



Age  Increased Risk over 40 years of age
Family History  Increased risk if immediate family members have glaucoma
High Pressures  Increased risk of developing nerve damage if you already have high pressures
Previous Eye Injury  The eyes drainage system can be damaged, causing an increase in pressure
Long term Steroid Use  Steroids can cause an increase in eye pressure
High Myopia (short-sightedness)  Higher incidence of glaucoma in people with moderate to high myopic prescriptons
Diabetes  Higher incidence of glaucoma in people with diabetes
Extremely High or Low Blood Pressure  May affect the blood supply to the optic nerve, causing nerve damage
Ethnicity  African Americans and Asians are at increased risk of glaucoma


Treatment for Glaucoma

      • Eye drops to lower the pressure in the eye


      • Laser Treatment

A laser beam is used to improve the drainage system in the eye, helping to lower the pressure


      • Surgery
        • The surgeon may create a tiny hole in the sclera (the white of the eye) to allow the fluid to drain more easily, lowering the eye pressure
        • Sometimes a hole is created in the iris (the coloured part of the eye) to allow the fluid to drain more freely

 Further information on glaucoma at