Eye conditions

A-C

Abrasion
An abrasion is an injury that happens when the skin is scraped off after it rubs against another surface.


Abscess 
An abscess is a lump that contains pus, which is made by the body during infection.

 

Achromatopsia 
An inability to see colours present from birth. It is caused by an absence or a defect in the light- sensitive retinal receptor cells called cones that provide sharp visual acuity and colour discrimination. 

 

Age-related cataract
Cataract that occurs as you get old. It is the most common type affecting both men and women from the age of 50 to 60 years.

 

Age-related macular degeneration
Degeneration of the photoreceptors in the macula or central region of the retina. This area of the retina is responsible for central vision, used for reading, seeing faces, and so on. Often associated with aging.

 

Amblyopia 
Also called lazy eye, this is a condition of decreased vision in one or both eyes and is not correctable by glasses or contact lenses.

 

AMD 
Acronym for age-related macular degeneration. A degeneration of the photoreceptors in the macula or central region of the retina. This area of the retina is responsible for central vision, for reading, seeing faces, and so on. Often associated with aging.

 

Anaesthetic
Anaesthetic is a drug used to either numb a part of the body (local), or to put a patient to sleep (general) during surgery.

 

Aniridia
A birth defect in which a child is born without an iris, so there is no way to control the amount of light that enters the eye. The only treatment is to use coloured eye lenses to reduce the amount of light entering the eye.

 

Anterior chamber 
The space in the eye that is behind the cornea and in front of the iris.

 

Antibiotic  
Antibiotics are medicines that can be used to treat infections caused by micro-organisms, usually bacteria or fungi. For example amoxicillin, streptomycin and erythromycin.

 

Astigmatism   
A condition where because of the shape of the cornea, light is spread over a diffused area rather than sharply focused on the retina.

 

Bacteria   
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and some others are good for you.

 

Bifocal glasses   
Glasses that have different refractive power at the top and at the bottom so that you can see near and far with the same pair of glasses.

 

Binocular vision   
The ability to maintain visual focus on an object with both eyes, creating a single visual image.

 

Blepharitis   
Common, persistent and sometimes chronic inflammation of the eyelids, resulting from bacteria that reside on the skin.

 

Blind spot  
A small area of the retina where the optic nerve enters the eye, this type of blind spot occurs normally in all eyes.

 

Blindness  
A person who is blind has severe sight loss and is unable to see clearly how many fingers are being held up at a distance of three metres or less (even when wearing glasses or lenses). However, they may still have some degree of vision.

 

Blood test  
During a blood test, a sample of blood is taken from a vein using a needle, so it can be examined in a laboratory.

 

Blurred vision  
Where an image of an object appears unclear. Not to be confused with double vision which is different.

 

Braille  
A system of raised-dot writing devised by Louis Braille (1809-1852). Each Braille character or cell is made up of six dot positions that are arranged in a rectangle made up of two columns of three dots each. A dot may be raised at any of the six positions, and each combination of raised dots corresponds to a letter of the alphabet, a punctuation mark, and another symbol.

 

Bridge  
The portion of the eyeglass frame which extends across the top of the nose. The nose supports 90 percent of the weight of glasses, so a properly fitting bridge is important for the fit and comfort of glasses.

 

Cataract   
Clouding of the natural lens of the eye. Most common in people over 60 years of age but also found in children (congenital or childhood cataract).

 

Cataract surgery  
Cataract surgery is used to remove the natural lens in the eye, replacing it with a clear, plastic lens.

 

Chalazion   
An enlargement of an oil gland with similar symptoms to a stye.

 

Clinical trial  
Clinical trials are research studies to test new types of treatments, preventions and diagnoses on patients.

 

Closed-angle glaucoma  
Serious form of glaucoma that can result in a sudden rise in intraocular pressure.

 

Colour blindness  
Colour blindness occurs when colour-sensitive cone cells in the retina do not properly pick up or send correct signals to the brain. True colour blindness is the inability to see any colour.

 

Colour deficiency  
Partial or total inability to see certain colours the way other people do.

 

Cone  
A type of specialized light-sensitive cell (photoreceptor) in the retina that provides sharp central vision and colour vision. Highly concentrated in fovea. Three classes of cones exist: short, medium, and long wavelength cones.

 

Congenital  
Congenital means a condition that is present at birth. The condition could be hereditary or may have developed during pregnancy.

 

Congenital cataracts  
Cataracts that are present from birth rather than ones that develop later in life.

 

Conjunctivitis  
Inflammation of conjunctiva or membrane that covers the white of the eye and inner surfaces of the eyelid.

 

Contact lens  
Thin plastic or glass lens designed to fit over the surface of the cornea, usually for correction of a refractive error, but can also be cosmetic (i.e. coloured contact lenses).

 

Cornea  
Clear structure that covers the front part of the eye including the iris and pupil.

 

Corneal abrasion   
A tearing, scrape or puncture of the cornea which covers the front of the eye. Can be painful but heals quickly.

 

Crossed eyes  
Also known as strabismus or squint, this condition is a visual defect in which the eyes are misaligned and point in different directions

 

Cyst  
A cyst is a fluid-filled sac or cavity in the body.

 

 

D-F

Diagnosis  
The process of identifying the nature and cause of a disease or injury through evaluation.

 

Diplopia  
The common name for this is double vision, where somebody sees two images of a single object instead of one.

 

Double vision 
Double vision is to see two images of a single object instead of one. The medical name for this is diplopia.

 

Drip 
A drip is used to pass fluid or blood into your bloodstream, through a plastic tube and needle that goes into one of your arteries or veins.

 

Fatigue 
Fatigue is extreme tiredness and lack of energy.

 

Fever 
A fever is when you have a high body temperature (over 38C or 100.4F).

 

Floaters  
Floaters are tiny, dark, shadowy spots that seem to 'float' in front of your eye, but are actually shadows from tissue particles in the back of the eye.

 

G-J

Gene 
Genes contain information that you inherit from your parents, such as eye or hair colour.

 

Genetic  
Genetic is a term that refers to genes. Genes contain characteristics inherited from a family member.

 

Genetic disorder 
A genetic disorder is a disorder caused by a fault in the genes. It is usually hereditary (runs in the family).


Glaucoma  
Glaucoma is the name given to a group of eye conditions where the pressure within your eye is too high. This causes damage to the optic nerve and because of this you can begin to lose your sight.

 

Immune system 
The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.

 

Incision  
An incision is a cut made in the body with a surgical instrument during an operation.

 

Inflammation 
Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

 

Intravenous  
Intravenous (IV) refers to the injection of blood, drugs or fluids into the bloodstream through a vein.

 

Iris 
The iris is the coloured part of the eye. It controls how much light enters the pupil and contains tiny muscles that make the pupil size bigger and smaller.

 

Jerky eyes 
Also known as nystagmus, this is an uncontrolled, rapid, jerky movement of the eyes, usually from side to side, but occasionally up and down or in a circular motion.

 

K-N

Long-sight 
Long-sight is a sight problem that affects your ability to see close up, but can affect all distances. Medically known as hypermetropia, the condition is a type of focusing error, and tends to get worse as you get older.

 

Macula  
The macula is a small spot near the middle of the retina. It is the part of the eye that is responsible for the central, sharpest part of our vision.

 

Medical history 
For a doctor to understand the care you may need they will collect a medical history from you and your carer. This information, together with other tests, helps the doctor assess and treat you.

 

Natural lens 
The lens inside your eye that you were born with.

 

Nystagmus  
Also known as jerky eyes, this is an uncontrolled, rapid, jerky movement of the eyes, usually from side to side, but occasionally up and down or in a circular motion.

 

O-R

Occlusion therapy  
A common treatment for the eye condition amblyopia. To improve vision, a patch is worn over the better eye. Patching the better eye makes the weaker eye work harder and not become 'lazy'

 

Ophthalmologist  
A doctor specially trained to diagnose and treat all eye disease and conditions.

 

Ophthalmoscope  
A tool for viewing the inside of the eye including the retina

 

Optic nerve 
A bundle of nerve fibres at the back of the eye, which carry messages from the retina to the brain.

 

Opticians  
Optician will sell and fit your glasses and contact lenses. They will do this from a prescription written by an ophthalmologist or optometrist.

 

Optometrist  
An optometrist examines and tests your eyesight, advises you on visual problems, and will prescribe, fit and supply your glasses or contact lenses. Optometrists are trained to recognize eye disease and will refer you to an ophthalmologist if necessary.

 

Orthoptist  
Orthoptists are the name of medical staff that work in orthoptics. They are skilled professionals trained in techniques to diagnose common childhood eye conditions such as squints and amblyopia. Once the tests are completed, decisions can be made as to what is the best treatment for you.

 

Paediatrician  
A paediatrician is the name given to a doctor who specialises in the care of children and babies. In an eye hospital they are quite unique because unlike many of the other medical staff they are not interested in the health of just your eyes, but of your whole body.

 

Patching 
A common treatment for the eye condition amblyopia. To improve vision a patch is worn over the better eye. Patching the better eye makes the weaker eye work harder and not become 'lazy'. The medical name for patching is 'occlusion therapy'

 

Photophobia  
An abnormal sensitivity to or intolerance of light.

 

Ptosis  
Ptosis is the term given to a droopy upper eyelid. Ptosis in children is due to the incomplete development of the muscle which raises the eyelid. This muscle is called the levator muscle. In children, if the eyelid covers the eye, it may stop vision developing correctly.

 

Pupil 
The pupil is a hole at the centre of the iris. The size of the pupil determines how much light enters the eye. The size is controlled by the muscles in the iris. Doctors often look at how the pupil responds to light to check that the visual system is working correctly. An increase in normal light makes the pupil get smaller and a decrease in light will make it grow bigger.

 

Red eye 
Red eye (sometimes called pink eye or conjunctivitis) is when the whites of the eyes become red and bloodshot as a result of an infection.

 

Red reflex test 
A common eye test that can check for abnormalities

 

Refractive Error  
Refractive error is a term used to describe long and short sight. Long sight affects your ability to see close up but can affect all distances. Short sight affects your ability to see distant objects.

 

Retina 
The retina is the nerve tissue lining the back of the eye, which senses light and colour and sends it to the brain as electrical impulses.


Retinal detachment  
The retina is the layer of nerve tissue at the back of your eye, on the inner wall. It allows the light that enters your eye to be turned into an image, by sending a message along the optic nerve to your brain. When this light sensitive layer becomes separated from the inner wall of the eye it is called retinal detachment.

 

S-U

Sight loss
Having sight loss means that even with glasses, you cannot see what you need to see.

Sclera 
The sclera is the outermost layer that surrounds the eye. The front part of the sclera joins the cornea at the very front of the eye.

 

Short-sight 
Myopia (short-sightedness) is a vision defect resulting from the eye being too long from front to back, or from the natural lens being too strong. The result is that there is a mismatch between the length of the eye and the focusing power of the cornea and lens. Myopia causes distant objects to appear blurred, whilst close objects can still be seen clearly.

 

Slit lamp 
The slit lamp is an instrument that consists of a high-intensity light source that can be focused to shine as a slit. It is used together with a microscope and is used in the examination of the anterior segment of the eye which includes the eyelid, sclera, conjunctiva, iris and cornea.

 

Snellen eye chart  
A test chart used for assessing visual acuity. Contains rows of letters, numbers, or symbols in graded sizes.

 

Squint   
A squint is a condition of the eye that causes one of the eyes to turn inwards, outwards or sometimes upwards, while the other eye looks forward. A squint can occur due to muscle or nerve problems in the eye or as a result of childhood illness or having long-sight. The common name for this is strabismus.

 

Strabismus  
Strabismus is a condition of the eye that causes one of the eyes to turn inwards, outwards or sometimes upwards, while the other eye looks forward. Strabismus can occur due to muscle or nerve problems in the eye or as a result of childhood illness or having long-sight. This is also referred to as a squint.

 

Stye  
A stye is a small abscess (painful collection of pus) on the eyelid and is an infection at the root of an eyelash.  It forms a red, sore lump similar to a boil or pimple. Styes generally occur near the edge of the eyelid.

 

Symptoms 
Symptoms are what a patient experiences about the condition or illness they have.

 

Ultrasound 
Ultrasound scans are a way of producing pictures of the inside of the body using sound waves.

 

V-Z

Visual acuity  
This is an evaluation of how well your eyes can see detail.

Vitreous   

A transparent, gel like substance that fills two-thirds of the back of the eyeball between the lens and the retina.