Listed below are some common eye defects and conditions with a brief explanation. Should you have any concerns regarding your vision or eye health we advise you undertake a full eye examination allowing us to investigate your symptoms or concerns in full.
SHORT SIGHTED (MYOPIA)
Short sighted people can see well close up but struggle with distance vision e.g. TV driving etc. In short sight or myopia the light is focused in front of the retina giving a blurred image. A minus powered lens is used to move the focus onto the retina.
Long Sighted ( Hyperopia)
Long sighted people have more difficulty seeing close objects e.g. reading VDU. Higher levels of long sightedness may also cause blurred distance vision. In long sightedness the light does not focus in time to reach the retina, this gives a blurred image. A positive powered lens is used to move the focus onto the retina.
Astigmatism gives blurring for distance and near vision. Here the front of the eye is distorted giving 2 points of focus. This is commonly described as a "rugby ball" shaped eye, the front surface has one steep curve and one flatter curve. This causes the light to focus in 2 points away from the retina. A lens with two components is required to correct the 2 focal points and move them on to the retina.
This is ageing sight. The eye naturally loses the ability to focus for near vision as we get older. This generally becomes a problem over the age of 45 years. The onset varies between people. Commonly people find they have to hold things further away to read and have more difficulty reading in poor lighting. Presbyopia is corrected using a positive powered lens, this may be in addition to any correction for short sight, long sight or astigmatism.
Amblyopia or Lazy eye is where the vision in one or both eyes is reduced even with spectacles. The eye shows no sign of disease or other abnormality. Amblyopia occurs when one eye does not recieve a clear image compared to the other in childhood.
There are 4 main causes of Amblyopia
Unless there is a turn in the eye or an obvious obstruction of the vision amblyopia often goes undetected until you have your eyes examined. Amblyopia is only treatable in childhood and earlier detection and treatment gives better outcomes.
Treatment varies depending on the cause, it may involve spectacles, occlusion of the good eye to encourage the lazy eye to work. Surgery may be required to straighten the eye in squint or remove the obstruction to vision in cataract.
Cataract is a clouding of the lens inside in the eye.
Cataracts are most commonly age related, most people over 60 will have some clouding of the lens which may or may not affect vision.
Cataracts may occur in younger people with conditions such as diabetes or other eye conditions. Some medications can also cause the early onset of cataracts.
Very occasionally babies are born with cataracts, these are called congenital cataracts.
A developing cataract may cause, blurred vision, glare in sunlight or when driving at night or fading of colour vision. Should you have any of these symptoms or other concerns about eye health you should have an eye examination.
Cataracts are removed by a surgical procedure where the cloudy lens is removed and a clear lens put in its place. This is generally performed under local anaesthetic and you can usually go home the same day.
Glaucoma is a condition where increased pressure inside the eye causes damage to the optic nerve which leads to loss of peripheral vision.
Glaucoma is easily treated if detected early however once vision is lost due to glaucoma it cannot be recovered.
Approximately 350,000 people in the UK suffer from glaucoma. Its prevalence increases with age.
Glaucoma can run in families, people with a direct relative with glaucoma i.e. brother, sister, parent or child have a 1 in 10 chance of developing the condition themselves.
People over aged 40 with a direct family relative with glaucoma are entitled to an annual eye examination paid for by the NHS.
There are two main types of glaucoma:
Primary Open Angle Glaucoma
Angle Closure Glaucoma
Age Related Macular Degeneration
There are 2 types of AMD, Dry and Wet
There is ongoing research into how nutrition affects the onset and development of AMD. These supplements cannot restore vision but may slow development of the condition.
For more information on AMD visit the Macular Society website.
Flashes and Floaters
Colour Vision Defects
The majority of colour vision defects are inherited. The most common red-green deficiency affects 8% of males and 0.4% of females. Occasionally colour vision defects are acquired later in life due to eye or brain disease or the long term use of some medications.
People born with colour vision defects generally adapt and are often unaware of the defect until colour vision screening is performed. There is no treatment for colour vision defects, in some cases tinted lenses may be used to help distinguish between colours but nothing will allow the sufferer to see colours normally.
Acquired colour vision defects can occur gradually e.g.cataracts which lead to difficulty distinguishing blue colours. Generally more severe acquired deficiencies are associated with other visual symptoms. Many acquired defects are reversible when the underlying condition is treated.
Some occupations have colour vision requirements, we will be pleased to advise you on this.
What is dry eye?
Our tears are made up of three layers secreted by glands in the eyelids. Dry Eye is an insufficiency in any of these layers.
What causes it?
There are many causes including age related changes, arthritis, central heating or dry, dusty working conditions.
What does it look like?
Often the eye is normal to look at, but symptoms include:
How can I make it better?
Artificial tear drops can be used during the day, and ointment can be used last thing at night. Different types of artificial tear drops such as Thealoz and Hyabak can be bought from us over the counter without a prescription.
You should use the drops often at first, and you can gradually decrease the drops to just a few times a day to keep your eyes comfortable. You will be able to judge yourself how often you need to use them.
What happens next?
The drops will relieve your symptoms, but will not cure your condition, you will probably need to continue to use the artificial tear drops.
In some cases a minor operation on the tear ducts can help to retain tears in the eye for longer, thus relieving the dry eye and reducing the need for the drops.
Nutrition and the Eye
It has been shown that a good diet full of fresh fruit and vegetables can play an important role in maintaining eye health, however we all know that eating 5 portions of fruit and vegetables every day isn’t always easy.
Ocuvite & Macushield dietary supplements for the eyes contain high potency antioxidant vitamins and zinc. Research has shown that vitamins help maintain healthy issues with the eye. Ocuvite also contains lutein a special antioxidant which helps protect the macula.