What is a Strabismus?
Strabismus is a disease in which the eyes are not properly aligned with each other. The extraocular muscles of the eye that is responsible for eye movement and strabismus involves a lack of coordination of the eyes, means extraocular muscles. Preventing the alignment, a squint cannot get proper binocular vision.
Strabismus be effectively treated if the treatment begins at very early stages. Wearing eyeglasses, using prism lenses, taking medication or other types of treatment can be helpful. Most of the cases the surgery is the most effective treatment for Strabismus.. Surgery will attempt to eliminate diplopia (double vision), and the patient will reach binocular vision. The surgery is also helpful for expanding the patient’s field of view, eliminating abnormal head posturing and improving depth perception of the patient.
Strabismus can lead to amblyopia.
What is Amblyopia? Lazy eye is the loss of vision in a strabismic eye.
If light from an object cannot be focused sharply on to the back of the eye then the child may develop a 'lazy' eye. This is also known as Amblyopia. It is not actually the eye that has become lazy; it is the special vision parts of the brain. The brain can only learn to see as clearly as the picture given to it by the eyes. If the brain has not been given a sharp, clear picture by the eye because of hypermetropia then it cannot learn to see clearly. If spectacles are worn to help focus the light then amblyopia may be prevented. Sometimes however even with correct spectacles vision may still be blurred. This is because the brain has not developed the power to see clearly. This is called Amblyopia. Amblyopia is more common in a child who also has a squint. See the VI Scotland Document on Amblyopia.
How is Hypermetropia diagnosed?
Sometimes parents and teachers notice, by the way a child acts, that their vision might be impaired. Children may have difficulty seeing text books at school. They may complain of eye strain or headache. Parents may notice that their child's eyes also occasionally squint. If parents discuss their concerns with their Family Doctor an assessment can be arranged. The family doctor may initially suggest an appointment with an optometrist.
An optometrist can diagnose hypermetropia during an examination. The level of hypermetropia can be measured by shining a light through different lenses into the eye. The level of hypermetropia is measured in focussing power units called 'dioptres'. Plus units are used to describe Hypermetropia. Mild hypermetropia is between zero and plus three dioptres. Moderate hypermetropia is between plus three and ten dioptres. Severe or 'high' hypermetropia is greater than minus ten dioptres.
What can be done to help?
Spectacles or contact lenses can usually sharpen vision. Sometimes the vision will not be perfect. This can be because of other problems with the eye such as microphthalmia, squint and amblyopia.
Other eye conditions such as squint can be treated by operations and wearing spectacles.
Laser surgery has been used successfully to treat short sight in adults and even some adults with long sight. It involves altering the shape of the cornea to focus light from objects on to the back of the eye. Because the level of hypermetropia can change during childhood and the early twenties it is never performed on children.