Common Eye Diseases and Problems

Xerophthalmia (Dry Eyes)

The increasing popularity of computers has made xerophthalmia more common.

Dryness of eyeballs is a primary cause of eyestrain.

As there are insufficient tears to moisturize our eyes, our eyeballs become dry and unhealthy – this leads to xerophthalmia.

Generally, we blink our eyes 20 times per minute to brush our eyeballs with tears and supply them with water and nutrients.

However, statistics show that the frequency of blinking drops substantially – to just one fifth of its normal frequency – when we are gazing at a computer screen, television or video game.

This is because our eyes tend to remain open more frequently when we are staring at a particular point.

This in turn reduces the tears on the surface of our eyeballs and makes our eyes drier.

If you want to rest your eyes, it is important to blink intentionally to maintain sufficient moisture on your eyeballs.

Presbyopie

The lenses in our eyes tend to lose their elasticity as we grow older, and we may find it more difficult to focus on nearby objects.

This eye defect is called presbyopia.

People who suffer from this may experience blurred vision when they are looking at nearby points; for example, reading a book.

The symptoms of presbyopia usually occur at around the age of 40.

If we avoid wearing reading glasses or bifocals, our eyes may get tired easily.

Besides, those who suffer from presbyopia may also experience headaches, tiredness and nausea if they do not wear suitable presbyopic glasses.

Presbyopia usually stops progressing at the age of 60 to 65.

However, it is a fallacy that presbyopia will stop progressing if you avoid wearing corrective glasses.

If you experience presbyopic symptoms at any age, you should have regular optical checks to ensure you are using the suitable corrective glasses.

Cataract

Cataract is a category of eye diseases caused by clumping of proteins which makes the lens opaque.

Other than heredity, factors like aging, diabetes, eyeball injuries, and ultraviolet ray damage to eyes can also cause cataract.

Symptoms of cataract:

• Difficulty in focusing on nearby objects, even with the aid of presbyopic glasses
• Cloudy or blurry vision
• Glare or dazzle (particularly in bright light)
• Double vision in one eye

Senile cataract may develop slowly without causing any pain or irritation, so it is difficult to recognize at the onset of it.

People who suffer from this disease experience blurry vision.

As the cloudy part of the lens gradually expands from its rim to its centre, more light rays are blocked and the opacity may increase to a point that the vision of the patient is seriously impaired.

Oral medicines and eye drops may slow down the progression of cataract at an early stage, but surgery will be required if it worsens.

Glaucoma

Glaucoma is a category of eye diseases, in which ocular hypertension (increase of intraocular pressure) occurs, leading to impaired vision as a result of optic nerve damage.

Intraocular pressure is mainly maintained by the circulation of liquid aqueous humor.

If the flow of the aqueous humor is stopped, the intraocular pressure will build up and add pressure to our optic nerves. Glaucoma is therefore resulted.

There are two types of glaucoma: chronic and acute, but both may lead to blindness if they are left untreated.

Chronic glaucoma develops slowly, and there are rarely any symptoms in the early stage of it.

Once the sufferer becomes aware of his or her partial loss of vision, the disease has already progressed significantly.

Regular eye tests are therefore important.

Acute glaucoma – the symptoms of which include severe headaches, eye pain and vomiting – occurs when the intraocular pressure suddenly increases.

Sufferers of acute glaucoma are mostly middle-aged females.

Acute glaucoma must be treated within 24 hours, or it may cause blindness.

Diabetic Retinopathy

Diabetic retinopathy is a category of eye diseases caused by complications of diabetes, which may eventually lead to blindness.

There are a lot of small blood vessels on the retina –they are especially vulnerable to poor blood sugar control.

As the viscosity of the blood of diabetics increases, it blocks the tiny blood vessels in the retina – causing lack of oxygen and nutrients of the retina.

This leads to retinal bleeding, and causes diabetic retinopathy eventually.

Not all diabetics will get diabetic retinopathy, but a high percentage of them will.

It is therefore very important to identify one’s diabetes.

Diabetic retinopathy may not occur if a diabetic keeps his or her blood glucose level under control.

The early symptoms of diabetes are:

• excessive thirst
• frequent urination
• sweet odour of urine
• fatigue

The early symptoms of diabetic retinopathy are almost unnoticeable.

Diabetics are advised to have their eyes examined regularly.