Your eyes may or may not be the windows to your soul, but they certainly allow us to get a good glimpse of the condition of your health, as well as eye diseases. It is important to detect these conditions early, for effective treatment and good prognosis. Having regular eye examination is one of the best things you can do for your eyes and general health.
Generally, we advise an eye examination every two years, and every year if you have progressive eye conditions such as cataract or glaucoma, diabetic, or you are over 40 years old with family history of glaucoma. Usually, at the end of the eye examination the optometrist advises you when you should come back for another test.
Cataract
The eye works similar to a camera. The lens at the front of the eye focuses the image onto the retina (which acts like the film in the camera) at the back of the eye. The image is sent from the retina to the brain via the optic nerve.
As we age, the lens becomes cloudy, due to development of opacities. This causes vision to become blurred and washed out. Glare may also be a problem due to light scattering caused by the opacities.
Most cataracts are slowly progressive; usually, there are at least a few years between when cataracts are first picked up by eye care practitioners and the time they need to be removed.
Causal factors for cataract include accumulative UV damage throughout one’s lifetime (exposure to sunlight), trauma, diabetes, smoking, medication (such as steroids), family history, and as a complication from other eye diseases.
Cataract cannot be removed by medicine, diet or exercise. It can only be removed by surgery, and in most cases, the cataract lens is replaced with an intraocular implant (IOL). The prognosis is usually very good. But as with all types of surgeries, complications can occur. This is best discussed with an eye surgeon.
Usually, you still need to wear spectacles after the cataract extraction.
Macular Degeneration
The macula is a small area at the very centre of the retina. It is responsible for your central and colour vision. Macular Degeneration (MD) is the name given to a group of degenerative diseases that affect this area of the retina. Usually, the result is progressive, painless loss of central vision (affecting the ability to see fine detail), and sometimes colour vision.
MD begins in the Retinal Pigment Epithelium (RPE), a layer of cells underneath the retina that is responsible for passing nutrients up to the retina and moving waste products down to the blood vessels underneath (the ‘choroid’). When this layer breaks down waste products from the retina build up underneath it, forming deposits, known as ‘drusens’, which are easily seen by eye care professional as yellow spots. As MD progresses, vision loss occurs because the RPE cells die.
MD has been broadly divided into “dry” and “wet” types. The dry type usually progresses slowly and the view has been that there is no effective treatment for this type. The wet type, however, progresses quickly and usually requires intervention to prevent further deterioration in vision. Treatment can be in the form of laser therapy or ocular injections.
In the early stages of MD, when drusens first appear, you may not realise anything is wrong and you may still have normal vision. That is the best time to detect the disease. Therefore, regular eye examination is important, especially as you get older, because the earlier the detection, the more vision you are likely to retain.
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Glaucoma
Glaucoma is an eye disease which causes damage to the nerve cells inside the eye, resulting in loss of peripheral vision, tunnel vision, and blindness, if not treated.
The exact cause of glaucoma is unknown, but it is thought that build up of pressure inside the eye (due to excessive aqueous production or poor drainage) plays a major role. Sometimes the pressure inside the eye can be very high, causing blurred, steamy vision and nauseating headaches. But more often than not, glaucoma does not have any symptoms until the late stage, when damage has already occurred. Glaucoma can also occur when the pressure of the eye is within normal limits.
Glaucoma detection involves looking at the structures of the eye, measuring the pressure inside the eye and performing a visual field test. Treatment usually involves instilling eye drops, laser treatment, and occasionally, surgery.
Glaucoma usually occurs after the age of 40 and the risk increases if there is family history of glaucoma or if the patient is on a certain type of medication, such as steroids.
Glaucoma can be picked up and treated early to prevent loss of vision. So regular eye examination is important, especially for the people in the high-risk groups.
Diabetic retinopathy
Diabetes affects all blood vessels in the body, including that of the eye. In diabetes, the blood vessel walls are weaker than usual, which can result in blood and plasma leakage from the blood vessels. In the eye, this leakage can cause retinal and vitreous (clear gel that fills inside the eye) damage, leading to loss of vision and eventually blindness.
Damage in the eye as a consequence of diabetes is called Diabetic Retinopathy (DR). This usually occurs after diabetes has been present for a number of years, especially when diabetes is not well controlled. Diabetic Retinopathy affects up to 80% of patients who have had diabetes for 10 years or more. Research indicates that up to 90% of new cases can be prevented if there was early detection and treatment.
If DR is detected, medical intervention, for example, laser therapy, can be used prevent further damage to the eye and vision.
Diabetic patients should have their eyes examined every year or sooner depending on the condition of their eyes.
Dry eyes
Dry eye is a term used when the eye feels dry, gritty and sore, but not painful. Despite the name, the irritation caused by dry eye may trigger excessive tears. It may be caused by ageing, allergies, diseases such as rheumatoid arthritis that disrupt the normal production of tears, some medicines such as antihistamines, benzodiazepines, diuretics, oral contraceptives, oestrogen hormone replacement therapy, antipsychotics and tricyclic antidepressants, and environmental factors such as low humidity. Open air, wind and sunlight may worsen dry eye.
Dry eye symptoms should be treated because if the eye is not properly lubricated, foreign material not washed away from the eye may lead to eye damage, infection and ulceration. Contact lens wearers are very much aware of symptoms of dry eyes, as it reduces the wearing time significantly and causes red and irritated eyes at the end of the day.
You can help prevent dry eye by: protecting your eyes from sun and wind by wearing wrap-around sunglasses; avoiding irritants such as smoke, dust, cosmetics and chlorine; avoiding air conditioners that dry the air; avoiding hair dryers;
using a humidifier at home; increasing your intake of omega-3 fatty acids (either through diet or supplements); and using artificial tears or lubricant regularly.
Artificial tears and lubricants are available as eye drops, gels and ointments. Eye drops are ideal for regular use during the day, and can be used as often as you need them. Ointments or gel may be used at night, or for severe daytime symptoms. Some people can be allergic to the preservative used in eye drops; if so, preservative-free preparations are available, although they are more expensive.
You should always wash your hands before instilling eye drops or applying eye ointment or gel. Be careful not to touch the eye with the container, as the contents may become contaminated with bacteria and later cause infection. Discard any unused medication once the packet has been open for 4 weeks.
If your eyes remain dry after a few days or if they are red, irritated, produce discharge or you experience reduced vision you should seek immediate medical attention.
Floaters
Eye floaters are little specks of debris floating through the vitreous fluid in the eyeball. Sometimes people may momentarily confuse them with dust or tiny insects floating across in front of the eye. However, they are within the eyeball and are not eliminated by rubbing or cleaning the front of the eye. Floaters occur within the gel (vitreous) fluid of the eyeball. Most floaters are the result of bits of cells that remain in the vitreous humor after birth and float around when the vitreous becomes more liquified later in life.
The characteristics of floaters can include:
They can be different shapes, such as tiny spots, flecks, clear little bubbles, threads or webs.
They are particularly visible when looking at a light-coloured area, such as a blue sky.
The floaters move as the eyes move, often with a slight lag.
Large floaters can present as diminished areas of vision, but this is very rare.
Under normal circumstances, eye floaters are absolutely nothing to worry about. Everyone experiences them from time to time and they cause no harmful effects. Floaters tend to increase with age because the vitreous humour pulls slightly away from the retina and degenerates with advancing years. This separation of vitreous humour from the retina can cause small shreds of jelly to break off and form more floaters. At first, this can be irritating. Eventually, the brain can become accustomed to the floaters and may decide not to ‘inform’ you of their presence.
Specks in front of the eyes are normally clearly visible when looking into a light background. However, if they start becoming visible in every background, suddenly increase in number and are accompanied by any loss of vision, it is vital that immediate medical advice is sought. This could be an early sign of retinal detachment.
If the retina has become detached or has a hole in it, you will begin to experience flashing lights before your eyes and you will also be aware of numerous floaters. These two symptoms will be accompanied by a loss of vision, so urgent medical advice is necessary. Surgery is required to seal any holes in the retina, or to re-attach the retina to the back of the eyeball.