Why is my eyesight so poor?

We are all familiar with people who wear corrective eye glasses because they are either long or short sighted or because they are elderly and have age-related eye changes. There are, however, other causes of poor vision (most of which can be prevented).

Albinism

Albinism is a hereditary condition in which there is lack of normal pigment in the body. The hair is white, the skin very fair, and the coloured part of the eye appears greyish. People with albinism usually have skin that is very sensitive to the sun, poor vision and may experience constant twitching of the eyes.

How to manage: Eye glasses with special lenses designed to improve vision and reduce discomfort that occurs when large amounts of light enter the eye.

Cataracts

The eye has a clear lens (very similar to a camera lens) which lets light in and allows it to get focused at the back of the eye where images are formed. This lens can become cloudy (whitish) resulting in poor vision. Cataracts can be congenital (present at birth) or one may develop them as they age.

What to do: If vision has been compromised, cataract surgery to remove the affected lens is often the cure. This is readily available in Kenya.

Poor nutrition

Vitamin A deficiency is one of the leading causes of blindness in children. Vitamin A is found in foods such as carrots, tomatoes, sweet potatoes, liver and fish. Due to this concerns, vitamin A was introduced as part of the routinesupplements given to children under the age of five years during clinic visits. (Vitamin A is also good for building your child’s immunity).

What to do: Give your child a diet rich in vitamin A and adhere to the supplementation program at the clinic.

Infections

Severe infections of the eye can lead to vision loss if they are not treated early and appropriately. For example, Rubella in a pregnant woman can cause vision loss in her unborn child. Rubella is prevented through vaccination. Trachoma is a contagious disease, caused by a virus, which affects the eyelids and the cornea and can lead to blindness. HIV has been associated with another virus known as Cytomegalovirus (or CMV) which can affect the eye.

Diabetes and High blood pressure

Poorly controlled diabetes and hypertension are some of the leading causes of visual problems in Kenya (and around the world). Usually, they damage the small blood vessels that line the back part of the eye (known as the retina).

How to manage: Controlling your diabetes and hypertension is the best way to prevent vision loss. If eye damage occurs, laser therapy can be used to treat the problem.

Glaucoma

In this condition, one develops blurred vision, inability to adjust eyes to darkened rooms and you begin to see coloured halos around lights due to increased pressure inside the eye. Eventual blindness may occur. The exact cause of the increased pressure is not well understood. It tends to occur in people above the age of 40 years and is a leading cause of vision loss globally.

How to manage: Medication or surgery may be used. Early detection is key and people over the age of 40 years are encouraged to go for regular eye check-ups.

Tumours

There are many different kinds of tumours which may appear in or around the eye. Some are cancerous whilst others are not. Some have been associated with vision loss whilst others can be managed without lasting damage to the eye.

How to manage: If you are found to have a tumour in or around the eye, seek specialist advice immediately. Tumours that are cancerous can spread to the brain and elsewhere, causing disability and eventually death.

Lazy eye

This is a condition which mainly occurs in young children. Usually the child is born whilst being able to see with both eyes. There is, however, a discrepancy between the visual capabilities of the two eyes. For example, one eye may be more near-sighted than the other or the two eyes may focus differently (‘cross-eyed’). The child will then subconsciously ‘opt’ to see through the eye with the better vision whilst the brain ignores input from the weaker eye.

With time, the weaker eye will lose its ability to see properly. If this problem is discovered early enough (generally before the age of five years), there are several strategies that can be used to help the weak eye will regain its strength.
What to do: All children need eye assessment at birth and again in the first two years of life. (If you have missed this window, you can still take your child for an eye examination). If there is weakness in a particular eye, one may give the child eye glasses with corrective lenses and if one eye cannot focus appropriately, the child may be given an eye patch to use. The eye patch is usually placed over the normal eye thus forcing the lazy eye to focus on objects the child wishes to see. With time, both eyes begin to focus on objects together.

Poor childbirth hygiene

Bacteria from a mother’s birth canal can be passed on to her baby’s eyes leading to infection. If not treated, this eye infection can lead to vision loss.

How to prevent: Globally, all babies born in hospital not only have their eyes cleaned after delivery, the medical staff are also obliged to put some antibiotic drops or ointment on them. In addition, women are encouraged to maintain high standards of hygiene and to get any vaginal infections treated prior to delivery.

Premature babies

Babies born prematurely are at an increased risk of getting visual loss. The exact reason why they lose their vision is not well understood but there have been concerns about the use of high concentrations of oxygen in incubators.

Eye injury

Most eye injury is subtle. It can occur in workers using toxic chemicals, metal welders and even carpenters. For this reason, workers in this fields must always eye protection (goggles or eye glasses). Head injury (for example after a car accident), can also result in internal damage to the eye with associated vision loss.

Colour blindness

This is a condition that is mainly found in males. It is an inherited condition. Usually, there are challenges distinguishing between the colours red and green. In severe cases, the person can see almost only in shades of black and white. Unfortunately, there is no way to prevent it.