Your eyes are remarkable devices that allow you to understand the environment around you, but they are also fragile and at risk of infection, damage or any other ocular disorder. The follwing pages contain information about the most common eye disorders, diseases and complaints as well as providing details about how to treat the problem if possible. This section is only meant to be a guide so it is important that if you do have a serious eye disorder or complaint you consult your optometrist for further advice.
SPOTS,FLOATERS AND FLASHESS
pots or floaters are small, semi transparent or cloudy particles within the vitreous, (which is the clear, jelly-like fluid that fills the inside of your eyes). They are quite common and usually, but not always, harmless.
Appearing as specks, threadlike strands or cobwebs, floaters are most visible when you look at a light background, such as the sky. Spots and floaters are caused by:
- Deterioration of the vitreous fluid, which is part of the natural ageing process.
- Certain eye diseases or injuries.
- Small flecks of protein or other matter trapped during the formation of the eye before birth.
Seeing flashes or streaks of light usually means that the vitreous is shrinking. It may become detached from the back of your eye. Vitreous detachment is common and rarely leads to serious eye problems. However, it is very important that these flashes are checked immediately as it may also be a symptom of retinal detachment, which although rare, requires urgent treatment.
Although spots and floaters are usually harmless, you should see your optometrist for a thorough eye examination when you first begin to see them or when you notice changes or increases in them. The optometrist can determine if what you are seeing is harmless or the symptom of an eye health problem in need of treatment.
AGE-RELATED MACULAR DEGENERATION
What is the macula?
Imagine that your eye is like a camera. There is a lens and an aperture (an opening) at the front, which both adjust to bring objects into focus on the retina at the back of your eye. The retina is made up of a delicate tissue that is sensitive to light, rather like the film in a camera.
The macula is found at the centre of the retina where the incoming rays of light are focused. The macula is very important and is responsible for:
- what we see straight in front of us
- the vision needed for detailed activities such as reading and writing
- our ability to appreciate colour.
What is macular degeneration?
Sometimes the delicate cells of the macula become damaged and stop working. We do not know why this is, although it tends to happen as people get older. This is called age-related macular degeneration. Because macular degeneration is an age-related process it usually involves both eyes, although they may not be affected at the same time. With many people the visual cells simply cease to function, like the colours fading in an old photograph - this is known as 'dry' degeneration. Sometimes there is scarring of the macula caused by leaking blood vessels and this is called disciform maculopathy. Children and young people can also suffer from an inherited form of macular degeneration called macular dystrophy. Sometimes several members of a family will suffer from this, and if this is the case in your family it is very important that you have your eyes checked regularly.
And now the good news
Macular degeneration is not painful, and never leads to total blindness. It is the most common cause of poor sight in people over 60 but never leads to complete sight loss because it is only the central vision that is affected. Macular degeneration never affects vision at the outer edges of the eye. This means that almost everyone with macular degeneration will have enough side vision to get around and keep their independence.
What are the symptoms?
In the early stages your central vision may be blurred or distorted, with things looking an unusual size or shape. This may happen quickly or develop over several months. You may be very sensitive to light or actually see lights that are not there. This may cause some discomfort occasionally, but otherwise macular degeneration is not painful. The macula enables you to see fine detail and people with the advanced condition will often notice a blank patch or dark spot in the centre of their sight. This makes activities like reading, writing and recognising small objects or faces very difficult.
What should I do if I think I have macular degeneration?
If you suspect that you may have macular degeneration but there are no acute symptoms you should see your doctor or optometrist (optician) who will refer you to an eye specialist. If you have acute symptoms then you should consult your doctor or local casualty department immediately. If macular degeneration has already been diagnosed in one of your eyes, and your other eye is getting acute symptoms, then you should go to the hospital that usually looks after you, or your local casualty department, as soon as possible.
What does an examination involve?
Firstly there will be an assessment of your vision in both eyes. Then you will be given eye drops which enlarge your pupil so that your eye specialist can look into your eye. The drops take about 20 minutes to work although their effect may last for several hours. Your vision will become blurred for a while and your eyes will become very sensitive to light, but this is nothing to worry about.
What is fluorescein angiography?
In some cases your eye specialist may decide that a fluorescein angiogram will also be needed. This involves taking a series of colour photographs of your retina with bright flashes of light. These photographs give an accurate map of the changes occurring in the macula and help your eye specialist to decide what is the best treatment for you. For the angiogram you will be given a small injection of special dye in your arm which then works its way around to your eye. This is not painful but you may feel a bit sick. A series of rapid pictures are then taken with a blue light over the next few minutes. There are few side effects, although some people find that they are dazzled for a while afterwards. You may also notice that the injection has left your skin with a faint yellow tinge from the fluorescein dye but this soon passes as it is excreted in your urine.
Can I be helped to see better?
Don't be discouraged - you can be helped to see better. With disciform degeneration laser treatment can help some people if the condition is diagnosed early enough. There are also a variety of optical aids which make use of the parts of the retina that are not affected. These range from brighter reading lights and simple magnifying glasses to more sophisticated equipment. Ask your doctor to refer you to the hospital low vision clinic.
What does laser treatment involve?
If you have disciform degeneration certain abnormalities on the macula can sometimes be treated by laser. This is usually done as an outpatient, and although it may cause some discomfort, is not painful. You will sit at a slit lamp and special contact lens are put into the eye to help focus the laser onto the macula. Unfortunately, with most people the areas of degeneration are in the middle of the macula, at its focal point. This means that treatment cannot be given because the scars produced by the laser would make central vision worse rather than better. Laser treatment is useful for about 10 per cent of people with disciform degeneration, and this always where people have reported their symptoms early. If successful it can prevent things getting worse, and sometimes bring back sight that is already lost. 'Dry' degeneration cannot be treated by laser.
What research is going on?
There is a great deal of research that is looking into the causes of macular degeneration and how it can be treated. With 'dry' degeneration there have been claims that certain types of medical therapy can halt
the condition, but this remains uncertain.
You can find out more from the:
Macular Disease Society
PO Box 247
Telephone 0990-143 573
For further information about RNIB services please contact us at:
Royal National Institute for the Blind
105 Judd Street
Telephone 0345-766 9999
Information provided by the Royal College of Ophthalmologists and the Royal National Institute for the Blind.
What is Amblyopia?
Amblyopia is the medical term for poor vision in one, or sometimes both eyes. It is generally caused by lack of use of one eye when the brain "favours" one eye over the other. In most cases, the eye itself is normal but is different in some way to cause this preference. In essence, amblyopia is a disorder of the brain cells that control the vision in one eye, not a problem with the eye itself. The brain cells diminish in size when they are not used.
The most common forms of amblyopia are strabismic and anisometropic.
Strabismic amblyopia occurs when a strabismus is present and the eyes are not aligned. The brain favours one eye over the other and the non-preferred eye is not adequately stimulated and the visual brain cells do not mature normally.
Anisometropia refers to the condition when the eyes have an unequal "refractive power". One eye may be nearsighted and the other is farsighted. Because the brain can not "balance" this difference, it picks the eye that is "easier" to use and develops a preference for this eye only.
Other causes of amblyopia include: cataracts, ptosis and trauma.
In most cases amblyopia is treatable. However, the success of treatment is dependent upon the initial level of vision, the amount of time the vision has been poor and the age of the child. The most important factor in treating amblyopia is compliance with the treatment protocol. Treatment requires "forcing" the brain to use the non-preferred eye. In most cases this means patching the normal eye for most or all of the day.
Glasses may also be required to "balance" an unequal refractive power between the two eyes.
If a cataract is present, this may need to be removed before amblyopia treatment can be started. The initial treatment period may be difficult for a child, as he/she is being made to use their "bad" eye. This usually lasts a short period of time, as their vision improves rapidly. It can not be overemphasised that the major reason for failure in the treatment of amblyopia is poor compliance with the treatment protocol.
Remember, amblyopia can be treated only when a child is young. If it is delayed until the child is older and more understanding, it may be too late!
Definition :-An inflammation of the eyelid edges.
Causes, incidence, and risk factors
Blepharitis has multiple causes but is usually caused by seborrheic dermatitis, a bacterial infection, or a combination of both, allergies, or infestation with lice (in the eyelashes). Blepharitis is characterised
by excess oil production in the glands near the eyelid, which creates a favourable environment for the growth of bacteria. Eyelids appear red and irritated, with scales that cling to the base of the eyelashes.
Blepharitis may be associated with repeated sty's and chalazion. Risk factors are poor hygiene, seborrheic dermatitis of the face or scalp and allergies.
Cleaning eyelids carefully will help restore the normal environment for the eyelid.
s- crusty and reddened eyelids
- swollen eyelids- itching and burning eyelids
- a granular sensation when blinking- loss of eyelashes
- eyes, bloodshot
- eye pain
Signs and tests
An examination of the eyelids is usually sufficient to diagnose blepharitis.
Depending on the cause, medications applied to the eyelid (topical), such as: antibiotics and/or corticosteroid (see corticosteroids - topical - low potency) will treat the infection and reduce the swelling.
Careful cleansing of the eyelids with a clean lint-free cloth soaked in warm water will help to remove the crusts. Often, a mild baby shampoo can also be used for cleansing.
If present, seborrheic dermatitis should be treated. Lice may be eradicated by smothering them with petroleum jelly applied to the base of the lashes.
The probable outcome is good with treatment.
Call for an appointment with your optometrist or GP if symptoms worsen or do not improve after careful cleansing of the eyelids for 2 or 3 days. Be aware of complications such as:
- Prolonged infection
- Injury to the eye tissue (corneal ulcer) from irritation
- Inflammation of the lining of the eye (conjunctivitis)
- Loss of eyelashes
- Scarring of the eyelids
Granulated Eyelids, Blepharitis
Blepharitis, or granulated eyelids, is a common problem that produces a red-rimmed appearance to the edge of the eyelids. This condition is often chronic and involves both the upper and lower lids.
Common symptoms include dandruff-like scales or grainy material adhering to the lashes and lid edges. The symptoms can include itching, burning, sticky, crusted eyelids on awakening, and a feeling of "something in the eye."
Granulated lids cannot be cured, but the symptoms can be controlled with treatment.
Treatment may consist of cleaning and removing any scales from the lid edges, frequent shampooing of the scalp and eyebrows, and ointment applied at bedtime when indicated.
Follow these instructions:
1. Apply a warm, moist hand towel to the closed lids for five to 10 minutes in the morning and at bedtime.
2. Following the warm compresses at bedtime, mix a solution of half "No Tears" baby shampoo and half warm water in the cap from a bottle of the baby shampoo. Put the solution on a wet wash cloth or cotton tip applicator, and gently scrub from side to side on the upper eyelids and lashes for 15 to 20 seconds.
3. Pull the lower lid down and away from the eyeball and gently scrub side to side along the edge of the lower eyelid and lashes for 15 to 20 seconds. Avoid scrubbing the eyeball.
4. Rinse the cloth and clean any remaining shampoo from the lids with clear, warm water.
5. When instructed, place a 1/4-inch strip of ointment under the lower lids at bedtime and rub the excess onto the lid edges.
6. If you have a problem with dandruff of the scalp and eyebrows, shampooing frequently with a shampoo containing selenium sulphide or pyrithione zinc (such as Head & Shoulders) will be helpful.
7. Continue this treatment for two to three weeks or until the problem is controlled. After an initial treatment period, it will most likely be necessary to continue to use warm compresses and lid scrubs from time to time to keep the lid scales under control
Conjunctivitis is an inflammation of the conjunctiva, the thin, transparent layer that lines the inner eyelid and covers the white part of the eye.
The three main types of conjunctivitis are infectious, allergic and chemical. The infectious type, commonly called "pink eye" is caused by a contagious virus or bacteria. Your body's allergies to pollen, cosmetics, animals or fabrics often bring on allergic conjunctivitis. And, irritants like air pollution, noxious fumes and chlorine in swimming pools may produce the chemical form.
Common symptoms of conjunctivitis are red watery eyes, inflamed inner eyelids, blurred vision, a scratchy feeling in the eyes and, sometimes, a pus-like or watery discharge. Conjunctivitis can sometimes develop into something that can harm vision so you should see your optometrist promptly for diagnosis and treatment.
A good way to treat allergic or chemical conjunctivitis is to avoid the cause. If that does not work, prescription or over-the-counter eye drops may relieve discomfort. Infectious conjunctivitis, caused by bacteria, can be treated with antibiotic eye drops. Other forms, caused by viruses, cannot be treated with antibiotics. They must be fought off by your body's immune system.
To control the spread of infectious conjunctivitis, you should keep your hands away from your eyes, thoroughly wash your hands before applying eye medications and do not share towels, washcloths, cosmetics or eye drops with others.
What is Double Vision?
If you see two of whatever you are looking at simultaneously, you may have a condition known as double vision, also referred to as diplopia. Double and blurred vision are often thought to be the same, but they are not. In blurred vision, a single image appears unclear. In double vision, two images are seen at the same time, creating understandable confusion for anyone who has it.
What causes double vision?
There are two possible causes.
1. Refractive. Light from an object is split into two images by a defect in the eye's optical system. Cataracts might, for example, cause such a defect.
2. Failure of both eyes to point at the object being viewed, a condition referred to as "strabismus" or "squint". In normal vision, both eyes look at the same object. The images seen by the two eyes are fused into a single picture by the brain. If the eyes do not point at the same object, the image seen by each eye is different and cannot be fused. The result is double vision. Why might eyes not point in the same direction? Possibly because of a defect in the muscles which control the movement of the eyes or in the control of these muscles through the nerves and brain.
What are its implications?
Double vision can be extremely discomforting. The brain acts to alleviate the discomfort by suppressing, or blanking out, one of the images. In young children, if this suppression persists over a continued length of time, it can lead to an impairment of the development of the visual system. The suppressed eye may get to the point where it is unable to see well, no matter how good the spectacle or contact lens correction. Doctors call this condition amblyopia. Since it is a result of a defect in the interpretative mechanisms of the eye and brain, it is more difficult to treat than a refractive condition (one having to do with the eye's ability to bend light).
How is it treated?
Treatment of double vision consists of eye exercises, surgical straightening of the eye or a combination of the two. Therapy is aimed at re-aligning the squinting eye where possible without surgery and re-stimulating
What is Dry Eye?
Tears serve to lubricate the eye and they are produced around the clock, but when insufficient moisture is produced stinging, burning, scratchiness and other symptoms are experienced and may be referred to as Dry Eye, Keratitis Sicca, Keratoconjunctivitis Sicca (KCS) or Xerophthalmia.
When we blink, tears form a film which spreads over the eye, making the surface smooth and optically clear and enabling good vision. There are three layers in the thin film of tears: an oily layer, a watery layer and a layer of mucus, each with specific function. The outermost, oily layer is produced by small glands at the edge of the eyelid (meibomian glands) and the main purpose of this layer is to smooth the tear surface and reduce evaporation. The middle, watery layer, is produced by small glands scattered through the conjunctiva, (the delicate membrane lining the inside of the eyelid) and by the large lacrimal (tear) gland. This layer cleanses the eye and washes away foreign particles or irritants. The innermost layer consists of mucus which allows the water layer to spread evenly over the surface of the eye. Without mucus, tears would not adhere to the eye.
What causes it?
Dry eye is caused when the tear gland produces insufficient tears. This can happen as part of the normal ageing process, and is more common among women so although the condition is not common it tends to occur with increasing age when it is not always noticed because the effect of dry eye tends to balance another age-related change; poor tear drainage. The result of this is a balance between not making too much lacrimal fluid (tears) and not being able to drain away much lacrimal fluid.
The main causes of an insufficient film of tears are deterioration of lacrimal tissue, dysfunction of the Meibomian gland destabilising the film of tears or a blockage in the excretory ducts of the lacrimal gland. People with Sjogren's syndrome are at risk of dry eye as part of a more systemic problem involving salivary glands and other sites of mucous membrane. Salivary gland involvement produces a dry mouth as well. This syndrome and dry eyes generally, may be found in people with rheumatoid arthritis.
Effects of the condition
In the early stages there is an increase in mucus strands and as the tear film breaks down, the mucin layer becomes contaminated. Where this contaminated matter cannot be dispersed it tends to move with blinking. Mucin is a substance that dries very quickly and rehydrates very slowly.
People with dry eye rarely have a sensation that the eye is dry but instead experience irritation, burning, a sensation of having a foreign body in the eye, mucus discharge and possible temporary blurring of vision.
Blinking may cause pain to people with severe forms of keratitis.
There is a series of tests designed to identify the cause and type of dry eye and these include Rose Bengal staining where a dye is used to identify problems and Schirmer's test which involves measuring the amount of wetting of a special filter paper. This can be done with or without topical anaesthetic that may be in the form of eye drops.
The aim of treatment will be to relieve discomfort and prevent corneal damage. In some situations relief may be found by blinking consciously when doing close or continuous work. It is also helpful to close the eyes for a spell from time to time.
Eye drops may be prescribed or purchased over the counter and since there is a variety, it may be helpful to try others if your present product does not suit you.
Some drops contain preservative which means they are safe to use for a month after opening, but although these drops are cheap and suitable for most sufferers, some people do not tolerate the preservative and may need to get prescription from the hospital pharmacy for a preservative free medication.
Lubricant ointments are also helpful, particularly at night. These are also available without preservative.
Some women benefit from hormone replacement therapy (HRT), especially those whose dry eye problems began around or after the menopause.
Antihistamines or certain types of travel sickness pills, inhibit tear secretion and symptoms can vary from day to day and be affected by general health.
Surgical procedures may be indicated if symptoms are severe despite drops. It involves closing the tear drainage holes in the eyelids permanently. It is a minor operation that is suitable for some patients.
Helping People with Dry Eye
Avoiding the following situations will minimise your risk of Dry Eye:
- Reduce the dry atmosphere caused by central heating by using a humidifier.
- Avoid car heaters, particularly at face level.
- Sit away from direct heat such as gas or electric fires.
- Use eyedrops just before activities which cause additional pain or discomfort such as television, reading, sewing and writing.
- Remember to blink regularly, particularly when doing close or concentrated work. Blink properly with full lid closure, not "half" blinking.
- Avoid smoky atmospheres.
Prognosis varies considerably and may depend in part upon individual lifestyle choices and overall health as well as the severity and cause of the condition. There is no definite cure, but people can usually be made more comfortable.
Use of artificial tear drops should provide immediate relief. These drops should be used forever. There is no need for regular clinic checks after starting the treatment. The drops may sometimes cause some feeling of stickiness or a little crusting of the lid.
EYELID AND TEAR GLAND DISORDERS
Surgery should completely cure infants, and there is no need for follow-up. In adults, surgery is only performed for severe disability, and the patient needs to be reasonably fit. It is a big operation and the success rate is less than l00%. After surgery the nose should not be blown, to allow for healing. If a plastic tube is placed, then watering will continue until its removal.
If Left Untreated
DRY EYE Without treatment, discomfort continues indefinitely. The eye will be more likely to get infected as well. WATERING EYE Continued watering of the eye can often be tolerated. Recurrent infections can also be treated. If the sac becomes infected it can swell up and cause tremendous discomfort. Then a lot of treatment is needed and surgery becomes necessary to remove the sac.The eyelids play a key role in protecting the eyes. They help spread moisture (tears) over the surface of the eyes when they close (for example, while blinking); thus, they help prevent the eyes from becoming dry. The eyelids also provide a mechanical barrier against injury, closing reflexively when an object comes too close to the eye. The reflex is triggered by the sight of an approaching object, the touch of an object on the surface of the eye, or the eyelashes being exposed to wind or small particles such as dust or sand.
Tears are a salty fluid that continuously bathes the surface of the eye to keep it moist. This fluid also contains antibodies that help protect the eye from infection. Tears are produced by the lacrimal (tear) glands, located near the outer corner of the eye. The fluid flows over the eye and exits through two small openings in the eyelids (lacrimal ducts); these openings lead to the nasolacrimal duct, a channel that empties into the nose.
If the lacrimal glands don't produce enough tears, the eyes can become painfully dry and can be damaged. A rare cause of inadequate tear production is Sjögren's syndrome. The eyes can also become dry when evaporation causes an excessive loss of tears, for example, if the eyelids don't close properly.
Nasolacrimal Duct Blockage
Blockage of the nasolacrimal duct (dacryostenosis) can result from inadequate development of the nasolacrimal system at birth, a chronic nasal infection, severe or recurring eye infections, or fractures of the nasal or facial bones. Blockage can be partial or complete.
Blockage caused by an immature nasolacrimal system usually results in an overflow of tears that runs down the cheek (epiphora) from one eye or, rarely, from both eyes in 3- to 12-week-old infants. This type of blockage usually disappears without treatment by the age of 6 months, as the nasolacrimal system develops. Sometimes the blockage resolves faster when parents are taught to milk the duct by gently massaging the area above it with a fingertip.
Regardless of the cause of the blockage, if inflammation of the conjunctiva (conjunctivitis) develops, antibiotic eyedrops may be needed. If the blockage doesn't clear up, an ear, nose, and throat specialist (otorhinolaryngologist) or an eye specialist (ophthalmologist) may have to open the duct with a small probe, usually inserted through the duct opening at the corner of the eyelid. Children are given general anesthesia for this procedure, but adults need only local anesthesia. If the duct is completely blocked, more extensive surgery may be needed.
Lacrimal Sac Infection
Usually, infection of the lacrimal sac (dacryocystitis) results from a blockage of the nasolacrimal duct. The infection makes the area around the sac painful, red, and swollen. The eye becomes red and watery and oozes pus. Slight pressure applied to the sac may push pus through the opening at the inner corner of the eye, near the nose. The person also has a fever.
If a mild or recurring infection continues for a long time, most of the symptoms may disappear, with only slight swelling of the area remaining. Sometimes, an infection causes fluid to be retained in the lacrimal sac, and a large fluid-filled sac (mucocele) forms under the skin. Recurring infections may produce a thickened, red area over the sac. An abscess may form and rupture through the skin, creating a passage for drainage.
The infection is treated with oral or intravenous antibiotics. Applying frequent warm compresses to the area also helps. If an abscess develops, surgery is performed to open and drain it. For chronic infections, the blocked nasolacrimal duct may be opened with a probe or by surgery. In rare instances, surgical removal of the entire lacrimal sac may be necessary.
Anything that irritates the eyes can also irritate the eyelids and cause swelling (lid edema). The most common irritant is an allergy, which can make one or both lids crinkled and swollen.
Allergic reactions may be caused by medications instilled into the eyes, such as eyedrops; other drugs or cosmetics; or pollen or other particles in the air. Insect stings or bites as well as infections from bacteria, viruses, or fungi can also cause the eyelids to swell.
Removing the cause of swelling and applying cold compresses may relieve the swelling. If an allergy is the cause, avoiding the allergen can alleviate the swelling; a doctor may also prescribe drug therapy. If a foreign object such as an insect stinger is lodged in the eyelid, it must be removed.
Inflammation of the eyelids (blepharitis) causes redness and thickening; scales and crusts or shallow ulcers often form on the eyelids, as well. Conditions that may occur with eyelid inflammation include staphylococcal infection on the eyelids and in the oil (sebaceous) glands at the edges of the lids, seborrheic dermatitis of the face and scalp, and rosacea.
Blepharitis may produce the feeling that something is in the eye. The eyes and lids may itch, burn, and become red. The eyelid may swell and some of the lashes may fall out. The eyes may become red, teary, and sensitive to bright light. A crust may form and stick tenaciously to the edges of the lid; when the crust is removed, it may leave a bleeding surface. During sleep, dried secretions make the lids sticky.
Blepharitis tends to recur and stubbornly resist treatment. It's inconvenient and unattractive but usually not destructive. Occasionally, it can result in a loss of the eyelashes, scarring of the lid margins, and even damage to the cornea.
Usually, treatment consists of keeping the eyelids clean, perhaps by washing them with baby shampoo. Occasionally, a doctor may prescribe an antibiotic ointment, such as erythromycin or sulfacetamide, or an oral antibiotic, such as tetracycline. When the person's skin is also affected with seborrheic dermatitis, the face and scalp must be treated as well.
A stye (hordeolum) is an infection, usually a staphylococcal infection, of one or more of the glands at the edge of the eyelid or under it.
An abscess forms and tends to rupture, releasing a small amount of pus. Styes sometimes form simultaneously with or as a result of blepharitis. A person may have one or two styes in a lifetime, but some people develop them repeatedly.
A stye usually begins with redness, tenderness, and pain at the edge of the eyelid. Then a small, round, tender, swollen area forms. The eye may water, become sensitive to bright light, and feel as though something is in it. Usually, only a small area of the lid is swollen, but sometimes the entire lid swells. Often a tiny, yellowish spot develops at the center of the swollen area.
Although antibiotics are used, they don't seem to help much. The best treatment is to apply hot compresses for 10 minutes several times a day. The warmth helps the stye come to a head, rupture, and drain. When a stye forms in one of the deeper glands of the eyelid, a condition called an internal hordeolum, the pain and other symptoms are usually more severe. Pain, redness, and swelling tend to occur in just a very small area, usually at the edge of the eyelid. Because this type of stye rarely ruptures by itself, a doctor may have to open it to drain the pus. Internal styes tend to recur.
A chalazion is an enlargement of a long, thin oil gland in the eyelid that results from an obstruction of the gland opening at the edge of the eyelid.At first, a chalazion looks and feels like a stye: swollen eyelid, pain, and irritation. However, after a few days the symptoms disappear, leaving a round, painless swelling in the eyelid that grows slowly for the first week. A red or gray area may develop underneath the eyelid.
Most chalazions disappear without treatment after a few months. If hot compresses are applied several times a day, they may disappear sooner. If they remain after 6 weeks, a doctor can drain them or simply inject a corticosteroid.
Entropion and Ectropion
Entropion is a condition in which the eyelid is turned in against the eyeball. Ectropion is a condition in which the eyelid is turned outward and doesn't come in contact with the eyeball.
Normally, the upper and lower eyelids close tightly, protecting the eye from damage and preventing tear evaporation. If the edge of one eyelid turns in (entropion), the lashes rub against the eye, which can lead to ulceration and scarring of the cornea. If the edge of one eyelid turns outward (ectropion), the two eyelids can't meet properly, and tears aren't spread over the eyeball.
These conditions are more common in older people and in those who have had an eyelid injury that caused scar formation. Both conditions can irritate the eyes, causing tearing and redness. Both can be treated by surgery, if necessary.
Eyelid TumorsNoncancerous (benign) and cancerous (malignant) growths can form on the eyelids. One of the most common types of benign tumor is xanthelasma, a yellow-white, flat growth that consists of fatty material. Xanthelasmas needn't be removed unless their appearance becomes bothersome. Because xanthelasmas may indicate elevated cholesterol levels (especially in young people), a doctor will check the person's cholesterol level.
Squamous cell carcinoma and the more common basal cell carcinoma, both cancerous growths, can develop on the eyelid as well as on many other areas of the skin. If a growth on the eyelid doesn't disappear after several weeks, a doctor may perform a biopsy (removal of a specimen and examination under a microscope), and the growth is treated, usually with surgery
What is iritis?
Iritis is the inflammation of the iris, the coloured portion of the eye. It has been known cause extreme pain, light sensitivity and sight loss, which is often the result of a disease in another part of the body. Most cases of iritis are recurring, in what are small attacks. Once treated the attack will usually respond to various medications. However, the condition may become sight threatening when left untreated. Medication for iritis varies, treatment that works for one will not always work with another.
What is the iris?
The iris is a circular muscle near the front of the eye. Besides giving colour to the eye, the iris controls the amount of light that enters the eye through the pupil. The iris is located behind the cornea (the clear protective layer of the eye) and just in front of the focusing lens. To see clearly, the proper amount of light must enter the eye. Just as the shutter controls the amount of light that enters a camera, the iris regulates the amount of light that enters the eye. The iris contains two muscles that control the size of the pupil opening. When too much light is present, the muscles cause the pupil to become smaller to reduce excessive light and glare. In dim light or at night, the muscles make the pupil larger to increase the amount of light entering the eye.
Sight loss can be prevented
Since iritis is an inflammation inside the eye, the condition is potentially sight threatening. Proper diagnosis and prompt treatment of iritis are essential. To minimise any loss of vision, the patient should have a complete eye examination as soon as symptoms occur. If diagnosed in the early stages, iritis can usually be controlled with the use of eye drops before vision loss occurs. If you are experiencing the symptoms of iritis or have other vision problems, you should obtain a complete eye examination.
What causes iritis?
In many cases, iritis is related to a disease or infection in another part of the body. Diseases such as arthritis, tuberculosis, or syphilis can contribute to the development of iritis. Infection of some parts of the body (tonsils, sinus, kidney, gallbladder and teeth) can also cause inflammation of the iris. In other cases, iritis may follow injury to the eye or accompany an ulcer or foreign body on the cornea. Often, the exact cause of the disorder remains unknown.
What are the symptoms of iritis?
The symptoms of iritis usually appear suddenly and develop rapidly over a few hours or days. Iritis commonly causes pain, tearing, light sensitivity and blurred vision. A red eye often occurs as a result of iritis. Some patients may experience floaters, small specks or dots moving in the field of vision. In addition, the pupil may become smaller in the eye affected by iritis.
How is iritis diagnosed?
A careful eye exam is extremely important when the symptoms of iritis occur, as inflammation inside the eye can affect sight and could lead to blindness. A slit lamp, which illuminates and magnifies the structures of the eye, is commonly used to detect any signs of inflammation. A diagnosis is often made on the basis of an eye examination. Since iritis can be associated with another disease, an evaluation of the patients overall health is sometimes necessary for proper diagnosis and treatment. In some cases, blood tests, skin tests, and x-rays may be conducted and other specialists may be consulted to determine the cause of the inflammation.
How is iritis treated?
Treatment of iritis is often directed at finding and removing the cause of the inflammation. In addition, eye drops and ointments are used to relieve pain, quiet the inflammation, dilate the pupil, and reduce any scarring which may occur. Both steroids and antibiotics may be used. The application of hot packs may also provide relief from the symptoms of iritis. In severe cases, oral medications and injections may be necessary to treat the condition. A case of iritis usually lasts 6 to 8 weeks. During this time, the patient must be observed carefully to monitor potential side effects from medications and any complications which may occur. Cataracts, glaucoma, corneal changes, and secondary inflammation of the retina may occur as a result of iritis and the medications used to treat the disorder.
POSTERIOR VITREOUS DETACHMENT
What is Posterior Vitreous Detachment?
Posterior Vitreous Detachment or PVD for short is a common condition that occurs in about 75% of people over the age of 65. As people get older the vitreous, a jelly-like substance inside the eye changes. This can cause Posterior Vitreous Detachment.
What is the Vitreous?
The vitreous is a clear jelly-like substance within the eye that takes up the space behind the lens and in front of the retina, the light sensitive layer at the back of the eye. It is 99% water. The other 1% consists of substances which are important in maintaining the shape of the vitreous. The outer part of the vitreous (the cortex) has the highest concentration of collagen. The vitreous is attached to the retina, more strongly in some places than others. When a PVD starts the jelly comes away from the retina.
Why does the vitreous detach?
The firm jelly-like substance of the vitreous changes with age. The central part of the vitreous becomes more liquid and the outer part (cortex) peels away from the retina. As it comes away from the retina it can cause the symptoms of Posterior Vitreous Detachment.
What are the Symptoms of PVD?
Many people are not aware that they have developed PVD but some notice symptoms such as floaters or flashing lights. Floaters can take many forms from little dots, circles, lines, to clouds or cobwebs. Sometimes people experience one large floater, which can be distracting and make things difficult to read.
The flashing lights that occur are also caused by the PVD. As the outer part of the vitreous detaches from the retina it can pull on this light sensitive membrane, especially where the vitreous is attached quite strongly to the retina. The pull of the vitreous in these areas stimulates the retina. This stimulation causes the sensation of flashing lights since the brain interprets all stimulation signals from the retina as light.
Can anything be done to help with the PVD?
Unfortunately at the moment nothing can be done medically for this condition, usually people find that the symptoms calm down after about six months and people do eventually get used to living with the floaters. The brain tends to adapt to the floaters and eventually is able to ignore them, so they then only become a problem in very bright light.
Will I lose any sight?
Posterior Vitreous Detachment does not in itself cause any permanent loss of vision. Your visual acuity should remain the same, that is, you will be able to see just as you could before the Posterior Vitreous Detachment started. You may have some difficulties to begin with because of the floaters and flashing lights though these do not cause permanent sight loss.
The only threat to vision is the small chance of a retinal tear leading to a retinal detachment. It is important to stress that retinal tears and detachments are much rarer conditions and that very few people with PVD go on to develop either of these problems
Are retinal tears serious?
Sometimes the vitreous is so firmly attached to the surface of the retina that as the jelly collapses it pulls quite strongly on the retina. In a few people this may lead to the retina tearing which in turn could lead to a loss of vision because of a retinal detachment.
Warning signs of a retinal tear or detachment could be an increase in size and number of your floaters, a change/increase in the flashing lights you experience or a blurring of vision. If you experience any of these symptoms you should seek medical advice within 24 hours. This is particularly important if you notice a dark 'curtain' falling across your vision, as this may mean that the retina has already partially detached. Early intervention may allow treatment of a tear before it becomes a detachment and increase the chances of a good recovery from a retinal detachment that has already occurred.
It is important to remember that PVD has been estimated to have occurred in over 75% of the population over 65, that PVD is essentially a harmless condition although with some disturbing symptoms and that it does not normally threaten sight.
Will I need to keep seeing my Optometrist?
Your optometrist will give you a thorough examination during your first visit. They will pay special attention to whether or not the retina is in any danger. If it isn't then they may not need to see you again. However if you begin to experience the symptoms warning of a possible retinal detachment, such as increased or definite change in floaters more severe flashing lights and/or a 'curtain' falling over your vision then a trip to the optometrist is again necessary.
Is there anything I can do to cope with these annoying symptoms?
Floaters can be particularly annoying. They get in the way of seeing things and can make some things difficult, for example reading a book. There is a way of trying to cope with this that some people find useful. If you move your eyes around you can create currents in the jelly within your eyes this can sometimes move the floater out of your direct field of vision. This works best if you have one large floater rather than lots of small ones. Making things bigger can also help while you have floaters so that you are able to see things around the blank spots the floaters cause. However most people find that with time the floaters become less and less of a problem.
Squint can be a complex condition and not every situation is covered in this factsheet, but your practitioner or eye specialist will be pleased to give you further advice, if needed. Your child will benefit from your support and encouragement during treatment, so do not be afraid to ask questions that will help you to understand more easily the condition and treatment.
What is a squint and how common is it?
A squint (also known as strabismus) is a condition that arises because of an incorrect balance of the muscles that move the eye, faulty nerve signals to the muscles and some refractive error (focusing faults). If these are out of balance, the eye may turn in (converge), turn out (diverge) or sometimes turn up.
Approximately five to eight percent of children are affected by a squint or a squint related condition, which means one or two in every group of 30 children. If your child appears to have a squint at any age from six weeks onwards, it is important to seek professional advice quickly. Many children with squints have poor vision in the turned eye.
What causes it?
There are several types of squint. The cause is not always known, but some children are more likely to develop it than others.
Sometimes a baby is born with a squint, although it may not be obvious for a few weeks. In about half of such cases, there is a family history of squint or the need for spectacles. The muscles are usually at fault.
Long Sight (Hypermetropia)
This can sometimes lead to a squint developing as the eyes are over focusing whilst trying to see clearly. The over focusing produces double vision. In an attempt to avoid this, the child may automatically respond by suppressing the image from one eye and turning it to avoid using it. If left untreated, a 'lazy eye' may result. The most common age for this type of squint to start is between 10 months and two years, but it can also occur up to the age of five. It is usually first noticed when a baby is looking at a toy, or at a later age when a child is concentrating on close work, such as a jigsaw or reading.
Following an illness such as measles or chickenpox, a squint may develop. This may mean that a tendency to squint has been present but, prior to the illness, the child was able to keep his or her eye straight.
In some cases a difficult delivery of the baby or illness damaging a nerve can lead to a squint.
Can a baby have a squint?
Yes, a baby can have a squint, especially if there is a family history of it. If this is suspected, it is important that the baby be referred for accurate assessment at the earliest opportunity. Sometimes a baby has what is known as a 'pseudo squint' which is related to the shape of the face, but a baby with a true squint will NOT grow out of it.
Isn't a squint just a cosmetic problem?
Certainly the appearance can lead to problems for the child, but a squint is NOT merely a cosmetic problem. If left untreated, it can lead to a permanent visual defect in the squinting eye.
How can I tell if my child has a squint?
Untrained people usually think a child has a squint if their eyes look different. This is not necessarily a squint. Squints are often difficult to detect, especially in younger children. Older children may complain of sight difficulties, such as double vision. If you think your child has a squint, ask your health visitor, child health clinic, GP or school doctor/nurse about a referral to an optometrist, ophthalmic medical practitioner or a hospital eye clinic for assessment.
What happens at the Hospital Eye Clinic?
Your child will be assessed to see whether a squint is present and what type of squint it is. The eye specialist will decide if further tests are necessary and if spectacles are needed.
Will my child have to wear spectacles?
Some squints, especially those that arise because the child is long sighted, respond well to treatment involving the wearing of spectacles. Children usually adapt well to wearing spectacles and professional advice from your practitioner will help you choose attractive spectacles for your child, should they be required.
Should their teachers know?
Yes. Children with a squint may find some problems with fine manual tasks, such as threading a needle. Fast ball games may present difficulties as the child may misjudge the speed and distance of the ball. With a squint depth judgement may be unreliable. If teachers are aware, they will be more tolerant of the missed catch! Also, children undergoing active therapy may need the co-operation of their teachers.
What treatment is available and will an operation always be needed?
No. An operation is not always needed. Treatment varies according to the type of squint. The main forms of treatment are:
SPECTACLES - to correct any sight problems, especially long sight.
OCCLUSION - this is patching the good eye to encourage the weaker eye to be used.
EYE DROPS - certain types of squint can be treated with the use of special eye drops.
SURGERY - this is used with congenital squints, together with other forms of treatment in older children, if needed. Surgery can be performed as early as a few months of age.
Why is an operation necessary?
Sometimes it is the only way of straightening the eye sufficiently for sight to be retained in the squinting eye. If performed at the appropriate time, results can be very good and satisfactory 3D vision can develop. There are occasions, however, when the result may only be cosmetic but the child's appearance in these cases is usually much improved. It is not uncommon for more than one operation to be necessary. This does not mean that something has gone wrong but that fine-tuning is needed to obtain the best results.
How is the operation done?
It involves repositioning the relevant eye muscles, often in conjunction with shortening one of the other muscles. This has the effect of weakening or strengthening muscles to get the best result.
What happens after the operation?
Your child may be in hospital for about 48 hours and will usually be allowed home the day after the operation. Some hospitals treat squint surgery as a day case, which may result in your child being very sleepy when going home. The eye may be red, but this settles down after a few days. Your child should be able to return to school after about 10 days. Regular follow-up visits to the eye specialist will be necessary for progress to be monitored. It is very important that these appointments are kept.
If your child wore spectacles before the operation to correct long sight or short sight and/or astigmatism, spectacles will still be needed, at least to begin with. This is because the operation corrects muscle imbalances, not focusing errors. As your child will be having regular follow-up care by the eye specialist and the orthoptist, tests to assess the need for spectacles will be carried out as part of this care. Some children may not need spectacles as they get older, but this must be judged according to each individual child's needs.
Can adults have a squint treated?
In certain cases, depending on the cause, a squint in an adult can be treated. Careful assessment will determine whether treatment is possible and may include surgery if appropriate.
REMEMBER. If in doubt, get qualified advice.
If you have any questions about your child's treatment, ask the eyecare professionals treating your child. If you think your child may have a squint, seek referral to a specialised eye clinic for assessment as early as possible. The earlier treatment starts, the better the results are likely to be.
If we think of the eye as a hollow, fluid-filled, 3-layered ball, then the outer layer is the sclera, a tough coat, the innermost is the retina, the thin light-gathering layer, and the middle layer is the Uvea.
The Uvea is made up of the iris, the ciliary body and the choroid (see diagram). When any part of the urea becomes inflamed then it is called Uveitis.
A big problem, when trying to understand Uveitis, for patients and doctors alike, is that there are many different types of Uveitis. This is because:
- The Uvea is made up of different parts. So if the iris is affected, the condition and its treatment could be totally different to when the choroid is affected.
- The inflammation in the Uvea very often affects other parts of the eye such as the retina and so a variety of other problems can be present to complicate the picture.
- Next there are a large number of medical conditions where Uveitis is a feature amongst the other symptoms of the disease. e.g. Behcet's Disease, Sarcoidosis and Toxoplasmosis, to name just three of them.
- There are many different types of causes of Uveitis [see under Causes].
The term intraocular inflammation is often used to cover the spectrum of uveitis conditions. As there is this wide variety of different conditions and complications, it follows that there are numerous ways that it presents itself. The degree and type of visual impairment and the type of treatment may vary considerably from patient to patient. Although the potential for confusion sounds high, as long as it is remembered that Uveitis is actually a number of different conditions, then it is possible to find out about your own particular case. It is, of course, very important, for both patients and doctors, to establish the exact type of Uveitis that exists, as far as it is possible, early on.
What causes Uveitis?
As just suggested, there are a number of quite different types of causes of Uveitis:
- It may result from an infection such as a virus (e.g. herpes) or a fungus (e.g. histoplasmosis).
- It may be due to a parasite such as toxoplasmosis.
- It may be related to Autoimmune Disease (with or without involvement of other parts of the body). This, essentially, is when our immune system recognises a part of our own body as foreign (albeit a small part, like one type of protein).
- Trauma to the eye, or even the other eye in the past, can lead to Uveitis.
- In many cases the cause is said to be unknown. This may well mean that the Uveitis is of the autoimmune type. The word "idiopathic" may often be used to describe this group
Another important way of classifying the different types of Uveitis is by describing the part of the eye that is affected. Very simply, there may be:
- Anterior Uveitis This affects the front of the eye, normally the iris (iritis) or the ciliary body (iridocyclitis). Iritis, strictly speaking is an older term for Anterior Uveitis but is still used frequently. Iritis is by far the most common type of Uveitis and also the most readily treated. Having said that, iritis is something that needs quite close monitoring because complications such as raised eye pressure and cataracts can occur.
- Intermediate Uveitis This affects the area just behind the ciliary body (pars plana) and also the most forward edge of the retina. (See the diagram above). This is the next most common type of uveitis.
- Posterior Uveitis This is when the inflammation affects the part of the uvea at the back of the eye, the choroid. Often the retina is affected much more in this group. The choroid is basically a layer rich in small blood vessels, which supplies the retina.
Tests and examinations
Because of the quite diverse types of causes of Uveitis and also due to the many other medical conditions associated with it, then you can expect to receive a number of tests and thorough questioning. All these are straightforward and painless enough but may seem far removed from your eye problem, e.g. back X-rays, but as said before, it is important to establish the correct type of Uveitis so that the best treatment can be planned.
How is Uveitis treated?
The treatment of Uveitis aims to achieve the following:
- Relief of pain and discomfort (where present)
- To prevent sight loss due to the disease or its complications
- To treat the cause of the disease where possible.
Like the varied nature of uveitis, the treatment of it may differ from case to case quite considerably. Corticosteroids are often the mainstay of treatment but now are, importantly, being joined by some other newer drugs, usually used along with the steroids. Various eye-drops are used, particularly to treat anterior uveitis.
What will happen to my eyes (prognosis)?
This, once again, varies considerably, but there is a growing confidence, especially with the newer drug treatments, that the eyesight can be stabilised over the long term. Uveitis as a disease should be regarded as incurable in the sense that it will never completely go away, but that is not to say that it cannot be controlled.
Would you like to find out more about Uveitis?
The group aims to provide information to those suffering from or interested in uveitis, in the form of leaflets, regular newsletters and by phone. It also helps people to contact other sufferers.
The Uveitis Information Group
Tel: 01806 - 577310