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Ophthalmics
Common Eye InfectionsEye infections occur when harmful micro-organisms such as viruses, bacteria and fungi invade the eyeball or any surrounding area. Micro-organisms may cause infections of the cornea which is the clear, top or outer layer of the eye as well as of the conjunctiva which is the thin, moist membrane that lines the outer eye and inner eyelids.1
Serious eye infections occur when the interior portion or part of the eye is affected.1
People who wear contact lenses may find that they often suffer from eye infections. This happens when contact lenses haven’t been properly disinfected and bacteria start to ‘build up’ on them. Some eye infections e.g. pink eye and blepharitis, (an infection of the eyelid), are common while others are rare.2
Read more about some commonly experienced eye infections.
Pink EyePink eye, also known as conjunctivitis, is a very common type of eye infection. It causes a redness and swelling of the conjunctiva, the clear, thin membrane that lines the eyelid and eye surface. 3
CausesA number of factors may be responsible for causing conjunctivitis e.g. infectious pink eye is caused by viruses or bacteria while chemicals, fumes and smoke can result in chemical conjunctivitis and allergies may be responsible for allergic conjunctivitis.3
Viral conjunctivitis
This contagious eye infection is easily spread by viruses that cause ailments like colds, sore throats and respiratory infections.3,4
Bacterial conjunctivitis
Bacterial pink eye, like viral conjunctivitis, is also contagious and spreads easily. It is caused by bacteria such as staphylococci and streptococci.3,4
Allergic conjunctivitis
Allergic conjunctivitis is caused by allergic reactions to fumes, cosmetics, drugs, house dust mite, animal dander and many others. Unlike viral and bacterial conjunctivitis, allergic pink eye is not contagious.3,4
SymptomsPink eye symptoms that are associated with all types of conjunctivitis include:3
- Eye redness
- Swollen, red eyelids
- More tearing than usual
- A feeling or sensation that there is something in the eye
- An itching or burning feeling
- Mild sensitivity to the light
Although different types of conjunctivitis have similar symptoms associated with them, unique signs help to differentiate one form of pink eye from another. This is demonstrated in the table below:4
| Viral conjunctivitis symptoms | Bacterial conjunctivitis symptoms | Allergic conjunctivitis symptoms | | | Watery eyes with a discharge | Watery eyes with a yellow or green discharge | Heavy tearing | | Discomfort in the eye with itchiness | Irritation accompanied by an itchy feeling may be experienced | Discomfort and itchiness | | Infection usually affects one eye | Infection usually affects one eye but can spread to the other | Affects both eyes |
Treatment5The type of treatment given or prescribed depends on what has caused the pink eye.
Viral conjunctivitis
This infection will disappear on its own and is therefore not usually treated.
Bacterial conjunctivitis
Antibiotic eye drops or ointment are normally prescribed or recommended for bacterial pink eye. The discomfort experienced with viral or bacterial conjunctivitis can be soothed by applying a warm compress, (clean cloth soaked in warm water), to the closed, infected eye.
Allergic conjunctivitis
Allergy medication, taken orally or in the form of eye drops, is indicated in the treatment of this condition.
Blepharitis (Eyelid inflammation)6Blepharitis is a common eye condition that causes the eyelids to be reddened, itchy and swollen. Scales appear at the base of the eyelashes and become coarser with time. The surface of the eye becomes irritated and forms crusts which may lead to the lids sticking together when one wakes up in the morning.
Causes- Blepharitis is normally caused by an excess growth of bacteria that is usually found on the skin
- Occasionally blepharitis is caused by allergies
Symptoms - A feeling or sensation of something being in one’s eye
- Burning of the eye
- Sensitivity to light
- Red and swollen eyes or eyelids
- Blurry vision
- Dry eyes
- Crusting of the eyelashes
TreatmentAlthough blepharitis cannot be cured it can be treated and controlled. If left untreated it can develop into a more serious condition that involves scarring or injury to the eye’s tissue.
The following steps can be taken to help treat and cleanse the eye: - Wet a facecloth in very warm water. Wring it out and then place it over the closed eyelids for 5 minutes. Rewet the cloth as necessary to keep up the desired temperature. This will help soften the crusts and loosen any oily debris
- Place the warm, wet cloth over the index finger and apply a diluted solution of 50 % baby shampoo or mild soap
- One eye should be cleansed at a time. Close the eye that is being cleansed and rub the facecloth or your finger over the eyelashes and lid edge several times using horizontal movements
- Rinse the eye with a clean, warm, wet facecloth. Pat the eye dry
Styes
A stye is a lump that forms along the edge of an eyelid.7
Causes8Styes are caused by staphylococcal bacteria which normally live on the surface of the skin. Under specific conditions these bacteria start to feed on dead cells and other debris causing a stye.
Symptoms7Normally a stye starts out as a red lump, (that looks like a pimple), along the edge of the eyelid. As the stye grows, the eyelid becomes swollen and painful and may cause the eye to water. The stye will continue to swell for 3 days whereafter it will break open and drain. Styes usually heal in a week.
Although styes may be painful or annoying, they are rarely serious.
TreatmentHome treatment is needed for most styes. If this doesn’t work, then one will need to consult with one’s doctor for a prescription eye ointment or eyedrops.9
Home treatment involves:7- Applying a warm, wet compress to the stye 3 to 6 times a day. This normally helps a stye to heal faster
- Allowing the stye to open on its own and not to be squeezed
- Not wearing eye makeup or contact lenses until after the stye has healed
A doctor should be consulted if:9 - A stye becomes very painful, grows larger quickly or continues to drain
- The redness and swelling around a stye spreads over the eyelid, inside the eyelid or over the eyeball
- One has problems with vision
- The stye does not begin to improve after 3 days of home treatment or does not heal in one week
Eye AllergyEye allergies, also known as allergic conjunctivitis, occur when an allergic reaction affects the conjunctiva10, (the thin, moist membrane that lines the outer eye and inner eyelids). 1
Allergic conjunctivitis can be divided into several subtypes of which the most common are seasonal allergic conjunctivitis (SAC) and perennial allergic conjunctivitis (PAC).10 It is thought that in South Africa about 6 million people suffer from allergies to pollen and that SAC is responsible for causing approximately 98 % of eye allergies.11
Causes of allergic conjunctivitis12Allergic conjunctivitis is caused when one’s eyes come into contact with substances called allergens that the body interprets and treats as harmful. Examples of allergens include pollen, dander, smoke and cosmetics. Pollen produced by trees and grasses, is often the allergen responsible for triggering or causing SAC.
When one is exposed to an allergen more than once, an allergic person’s body will react by producing specialised chemicals called antibodies. An allergic reaction takes place when allergens in the air make contact with antibodies on the eye. This causes chemicals such as histamine to be released. Histamine causes the eyes to itch, swell and produce more tears than normal.
Symptoms10
Both eyes are normally affected by allergic conjunctivitis. The primary symptom experienced with eye allergy is itching. In addition to this the following symptoms may also be experienced: - Redness
- Tearing
- Burning sensation
- Blurred vision
Treatment10Avoidance is the mainstay in the treatment of allergies. However, this is not always possible.
Antihistamines, taken orally or topically, (in the form of eye drops), are effective in the treatment of allergic conjunctivitis and can be recommended or prescribed to you by your healthcare professional.
Dry eyesDry eye is a condition that can develop under many circumstances and affects millions of people of all ages.14
CausesDry eye occurs when the natural tear film, (a thin layer of tears that protects the surface of our eyes), is destroyed.13
Damage to the surface of the eyes, (the cornea and conjunctiva), causes symptoms of dry eye.13
Common causes of dry eye include:14- Aging
- Dry environment or workplace (wind or air conditioning)
- Sun exposure
- Smoking or second-hand smoke exposure
- Cold or allergy medicines
- Eye injury
- Previous eye surgery
Symptoms14- Burning, scratching or stinging sensation
- Eyes become strained or tired after reading, even for a short period of time
Treatment13The following factors should be implemented to improve dry eyes: - Instil artificial tears, that can be purchased from your local pharmacy, into the eyes
- Don’t smoke
- Avoid second-hand smoke, direct wind and air conditioning
- Use a humidifier particularly in winter
- Purposefully blink more often
- Rest one’s eyes
Anyone, whose eyes do not respond to any of the above mentioned measures within a few days, should consult with their doctor.
Cataracts
A cataract is a clouding of the lens, which helps us to focus on what we see.15
Causes- Age
Cataracts evolve as part of the normal aging process. In fact most people who develop cataracts are over the age of 60 years15 - Diabetes
When blood sugar levels are above the safe range changes can occur to the eye and result in cataracts16 - Overexposure to ultraviolet or UV radiation e.g. sunlight, tanning booths or sunlamps16
- Disease inside the eye e.g. glaucoma, (increased pressure inside the eye), uveitis (inflammation of the middle layer of the eye), retinitis pigmentosa, (damage to the retina of the eye)16
- Family history or genetics16
- Eye injury16
- Long-term use of steroid medications16
- Frequent x-rays or radiation treatments to the head16
Symptoms- Impaired vision e.g. one may find difficulty reading or driving15
- Cloudy, fuzzy, foggy vision17
- Glare – if one has cataracts, one may find it harder to see when there are bright lights on e.g. looking at the oncoming headlights of a car15
- Double vision17
- Difficulty performing daily activities because of vision problems17
Treatment18The only effective method of treating vision loss caused by cataracts is surgery.
Cataract surgery is a common procedure that involves the removal of the clouded lens or cataract from the eye and replacing it with an artificial lens called an intraocular lens implant (IOL).
Surgery may often not be necessary or may even be able to be delayed for months or years. This is because many people are able to maintain vision with the help of eyeglasses, contact lenses and other vision aids.
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