Better vision within reach

2017-11-01 06:01

During cataract surgery, the cloudy lens inside the eye is removed and an artificial lens is implanted.

The intra-ocular lens used is determined by visual needs and personality.

The cost of the procedure is a reality. Medical funds prescribe a limit and when exceeded, the difference is pay­able by the patient.

Most prefer having both eyes correc­ted for distance vision and to wear glasses for reading, but the surgery is commonly done for driving and sport.

For presbyopia, so-called long arm syndrome, the standard age is 45 years, when it becomes impossible to read without glasses. Some prefer not wearing glasses, since the constant taking off and putting on of glasses becomes tedious.

A person could still wear bi- or multifocal glasses, but the distance part would then require a small correction.

With singular vision correction, reading vision helps near-sighted people and also helps for reading without glasses. Glasses are worn for distance focusing.

Monovision correction is performed where the dominant eye is used for distance vision.

Prior to correction, it is vital to wear a contact lens for an experimental period, ensuring sight and function. Two thirds of people can adjust, but to the rest, it is bothersome.

The upside is, no glasses are needed to watch television or read a book, but you need an adjustment period.

This correction is not recommended for active persons or athletes due to limited depth perception.

Multifocal lenses or premium lenses vary to correct long-distance vision and near-sighted vision, letting the brain filter the light.

Halos and glares around lights from distance vision is possible and thus not for night-time drivers.

Some lenses focus on book reading, the so-called 40 cm reading distance, whilst others focus on a further distance, 60 cm from the sharp focus point.

The brain typically adjusts to the images in three months. One is focused upon intensely and the other is supressed and known as neural adaptation or sensory adaptation.

Very few people, about 3,7%, do not adapt at all.

Sufficient background lighting is essential for the efficacy of these lenses. A total of 60% of the light entering the eye is used for distance vision and the remaining 40% for near vision.

If you are among the 3,7% of the people whose lens does not suffice, your ophthalmologist can change it to a monovision lens.

Astigmatism is defocussed or blurred vision due to the eye being shaped like a rugby ball, not a soccer ball.

The rays of light cannot be focused at a point to obtain clarity. The lens is implanted into the eye to correct the astigmatism.

The first of the so-called trifocal lenses have already appeared.

A research group is currently conducting phase 3 studies for an oil-filled lens mimicking the eye’s natural focus action.

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