Vision Needs
Astigmatism
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.
Blepharitis: a
chronic or long term inflammation of the eyelids and eyelashes. It
affects people of all ages. Among the most common causes of blepharitis
are poor eyelid hygiene, excessive oil produced by the glands in the
eyelid, a bacterial infection (often staphylococcal), or an allergic
reaction.
Cataracts: a
painless, cloudy area in the lens of the eye. A cataract blocks the
passage of light from the lens to the nerve layer (retina) at the back
of the eye, and may cause vision problems. Cataracts can be surgically
removed and replaced with an intraocular lens implant, restoring vision.
How a toric lens corrects astigmatism?
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The
irregular shape of an astigmatic eye cornea and/or lens produces two
focusing points in front of or behind the retina in blurred vision.
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A toric lens corrects the refractive errors, creating a single focal point in the retina where vision is sharpest. |
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