There are five and half million people in the U.S. suffering from cataracts, a clouding of the lens that affects vision. The term cataract comes from the Greek word for waterfall, from the mistaken belief that it was humor causing ripples that clouded vision. Various treatments for cataract have been around since antiquity, each progressively improving on its predecessor. Only in modern times, have treatments been available that match the healthy crystalline lens' characteristics. The major advancements in vision enhancement using replacements lenses have occurred since the 1940's.
The earliest recorded procedure, know as couching, is recorded in 5th Century B.C. Sanskrit manuscripts. This procedure moves the lens out of its natural pocket out of the way. Although the cataractic lens was out of the way, there was nothing to replace it and improve vision problems.
A practice called needling is recorded in the First Century A.D. This procedure would break up the clouded lens, allowing it to be reabsorbed naturally. Today's modern procedures use advanced technology like lasers to do similar things.
In the 18th Century, the cataract lens was removed through various methods where the lens could be squeezed through a small incision. By the early 20th Century, a small suction cup was invented to ease the extraction of the lens. In all these procedures, the cloudy lens was removed, but nothing replaced the lens to help improve other vision problems.
In the 1940s an intraocular lens was developed to sit in the aphakea, the space voided after the removal of thy crystalline lens. These lenses were based on typical corrective lenses and were only capable of correcting lenses for one distance. Patients would still be required to wear corrective glasses for near vision correction.
An adaptation of lens replacement surgery, called mono-vision correction, uses lenses of varying power to correct the dominant eye for distance vision and the non-dominant eye for near vision. Patients could easily check ahead of time to see if mono-vision correction would work by testing a pair of glasses using the same techniques.
Around the turn of this century, advancement is lens technology introduced several multifocal intraocular lenses for enhanced vision correction. There are several options now available to correct vision for all distances using the same lens. The leading multifocal lens is AcrySof ReSTOR IOL. It uses apodized diffractive and refractive technology to mimic the way the natural crystalline bends light into the retina.
The apodized portion of the lens lies in the interior of the lens and progresses through very small steps of increased thickness. This allows for good focusing on near objects, making these IOL. Around the edges of the lens is the refractive portion, which allows the parallel light when focusing at a distance to enter the eye when the pupil is more dilated. Although AcrySof ReSTOR lenses cannot completely accommodate as well as the natural crystalline lens of the eye, they come much closer. More than 80 percent of patients can break their spectacle dependence.
As the century progresses, technology will advance even further, offering ophthalmologic surgeons greater ability to restore vision using multi-focal lenses that approach the abilities of the human eye. It is important to find a vision correction specialist who keeps abreast of the latest vision correction technology.
History of cataract treatment
The earliest recorded procedure, know as couching, is recorded in 5th Century B.C. Sanskrit manuscripts. This procedure moves the lens out of its natural pocket out of the way. Although the cataractic lens was out of the way, there was nothing to replace it and improve vision problems.
A practice called needling is recorded in the First Century A.D. This procedure would break up the clouded lens, allowing it to be reabsorbed naturally. Today's modern procedures use advanced technology like lasers to do similar things.
In the 18th Century, the cataract lens was removed through various methods where the lens could be squeezed through a small incision. By the early 20th Century, a small suction cup was invented to ease the extraction of the lens. In all these procedures, the cloudy lens was removed, but nothing replaced the lens to help improve other vision problems.
Monofocal IOL
In the 1940s an intraocular lens was developed to sit in the aphakea, the space voided after the removal of thy crystalline lens. These lenses were based on typical corrective lenses and were only capable of correcting lenses for one distance. Patients would still be required to wear corrective glasses for near vision correction.
An adaptation of lens replacement surgery, called mono-vision correction, uses lenses of varying power to correct the dominant eye for distance vision and the non-dominant eye for near vision. Patients could easily check ahead of time to see if mono-vision correction would work by testing a pair of glasses using the same techniques.
Multifocal IOL
Around the turn of this century, advancement is lens technology introduced several multifocal intraocular lenses for enhanced vision correction. There are several options now available to correct vision for all distances using the same lens. The leading multifocal lens is AcrySof ReSTOR IOL. It uses apodized diffractive and refractive technology to mimic the way the natural crystalline bends light into the retina.
The apodized portion of the lens lies in the interior of the lens and progresses through very small steps of increased thickness. This allows for good focusing on near objects, making these IOL. Around the edges of the lens is the refractive portion, which allows the parallel light when focusing at a distance to enter the eye when the pupil is more dilated. Although AcrySof ReSTOR lenses cannot completely accommodate as well as the natural crystalline lens of the eye, they come much closer. More than 80 percent of patients can break their spectacle dependence.
As the century progresses, technology will advance even further, offering ophthalmologic surgeons greater ability to restore vision using multi-focal lenses that approach the abilities of the human eye. It is important to find a vision correction specialist who keeps abreast of the latest vision correction technology.