Astigmatism is a common visual distortion caused by an irregularly shaped cornea. The surface of the cornea is toric, oblong in shape like a football, instead of perfectly round like a basketball. Light rays passing through an oblong cornea bend unequally, causing two focusing points. Consequently, vision is blurred at most distances.
Astigmatism is usually hereditary, although factors, such as low light levels and too much work done close up can contribute. Over time this condition may increase slowly, but generally over a lifetime it remains relatively stable. Forty-five percent of people who require vision correction have some degree of astigmatism. Symptoms include squinting, occasional headaches and eye strain. In most cases, astigmatism is accompanied by myopia or hyperopia.
Bifocal/Multifocal Lens: contains two or more viewing zones allowing for one to see distant, intermediate and near objects.
Astigmatism is usually hereditary, although factors, such as low light levels and too much work done close up can contribute. Over time this condition may increase slowly, but generally over a lifetime it remains relatively stable. Forty-five percent of people who require vision correction have some degree of astigmatism. Symptoms include squinting, occasional headaches and eye strain. In most cases, astigmatism is accompanied by myopia or hyperopia.
Bifocal/Multifocal Lens: contains two or more viewing zones allowing for one to see distant, intermediate and near objects.
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