History of contact lenses

Despite the fact that contact lenses are widely used relatively recently (roughly from the beginning of the sixties of the last century), the history of contact lenses includes more than five hundred years.

More in 1508 by Leonardo da Vinci (Leonardo da Vinci) described lens which when placed on the eye had to change the optical properties of the eye. The archive of the great artist and scholar of Italian Renaissance figure has "eyes on him with a plastic tray filled with water." The front surface of the pan is formed as a convex lens. These "liquid glasses" were the prototypes of modern contact lenses.

In the manuscripts of Rene Descartes (René Descartes) of the 1637 figures are another interesting device directly related to contact lens - This device consisted of a tube which is filled with water, one end of the tube was closed by a lens, and the other puts directly to the eye. Thus it was created the first optical system on the principle of action is similar to modern contact lenses.

The use of ophthalmic lenses, are in direct contact with the eye, were first theoretically substantiated in 1730. De Lamour (De L'amour) in his dissertation. Later, in 1801 experiments with short tube filled with water and equipped with a bikonveksnoy lens held Thomas Young (Thomas Young). With the help of this device for the shortcomings of refraction of the eye. And published in 1845 by the writings of the English physicist John Herschel (John Herschel) theoretically substantiated the contact correction of corneal astigmatism.

Based on the handset Descartes-Jung, for the correction of vision problems associated with the deformation of the cornea was created Hydroscope. This phase in the history of the contact lens should be regarded as an intermediate, as these devices are inconvenient, cumbersome, besides depleted skin around the eyes. This arrangement is a geometric ochkovuju system performance in a half-mask. Podochkovoe space is filled with water, through which the contact with the eyes. Despite the inconvenience, some patients still used Hydroscope through extreme need for contact lens.

A year later, in 1888, a Swiss ophthalmologist Adolf Fick (Adolph Fick) published in the journal «Archiv fur Augen Heilkunde» article called "contact points". In this article Fick described his device for contact lens as follows: "Glass cornea with a radius of curvature of 8 mm with a basis sits 7 mm glass sclera, the latter has a width of 3mm and corresponds to a sphere with a radius of curvature of 15 mm. Glass cornea with parallel walls on the inside and outside sanded and polished; Likewise, ground and polished glass and the free edge of the sclera. The weight of one of the contact points 0.5. " It was the first reported contact lenses.

First Fick conducted experiments on animals and only then dared to go to the human eye. Having made first plaster cast, Fick blew his first lenses.

In the same year, it was reported on the use of such contact lenses by the French ophthalmologist Eugene Kalt (Eugene Kalt) for the treatment of patients with keratoconus. Further details about wearing contact lenses have been published in the dissertation August Müller (August Müller) in 1889. The theory of contact lens, developed by Muller, based on the number of tests carried out on their own myopic eyes. Muller used contact lenses made optometrist Himmler, knowing nothing about the opening of Fick. So August Mueller also enlisted a pioneer in the field of optical correction.

The first scleral contact lenses were, that is, have a large diameter and were similar to single-wall eye prosthesis. The optical part of a contact lens was based on the sclera, the central optical part is refracted rays. Podlinzovogo space for filling liquid used with glucose or saline.

In the future, contact lenses have improved various specialists ophthalmologists and optometrists (including D. Sulzer (1892), G. Dore (1892) and others). Muller, known glassblower from Wiesbaden (Germany), has established the first production of contact lenses. Although the lens Mueller were just ordinary eye prosthesis, they had a number of advantages over previous designs. Thus, scleral part was made of white glass, and - the optical transparent.

In the years 1914-1924 buy contact lenses became available through mass production of contact lenses in Jena renowned German optical company Carl Zeiss. To be able to select the optimum lens shape for a particular eye, the company produces sets of contact lenses. After the "fitting" for the most suitable lens is made individually scleral lens. Also unlike lenses Muller Zeiss lens provides better portability due to polishing.

Making scleral lenses made of glass Mueller and improved form of optical lenses Zeiss crowned at the end of the twenties the first phase of the history of contact lenses. The main achievements of this period - the development of mass production of optically perfect scleral lenses. The second stage includes the time from 1929 to 1948, and is marked by efforts to improve the existing models in the form and adaptation.

In 1929, Istvan Chapodi (Istvan Csapody) proposed a method of individual selection form scleral lens on the eye of the casts made with the help of special plastics (negokola, for example). But the method is not spread through unsafe, uncomfortable and expensive.

In the future, a large contribution to the improvement of methods of selection and manufacturing of contact lenses made by Hungarian Istvan Chapodi ophthalmologists, Joseph Dallos (Josef Dallos), Derfi I. (1938). They proposed the technique of making individual scleral lenses by first removing the molds from the eye and training based on these forms. In the 30 years of XX century, have been actively practicing the casting of the lens pattern. This production method was first applied to American optometrist Obrigom Theodore (Theodore Obrig), which revealed that contact lens intolerance is caused by pressure on the region of the limbus. Thus, the third period of the history of the contact lens is characterized by the start serial production of contact lenses, their widespread use in optics, the beginning of use for diagnostic purposes, as well as the prolonged ocular dosage form in combination with the saturation of pharmacological agents.

Until 1936, all scleral lenses were made of glass. Derfi proposed plastic as material for the manufacture of contact lenses. A year later, V. Faynblum American ophthalmologist, began to produce plastic scleral lenses and the glass part of the cornea. In the same year Derfi Obrigom and contact lenses were made entirely of plastic - polymethylmethacrylate. Optical center of the scleral lens was placed in front of the cornea, peripheral support or optical part adjacent to the sclera and held the lens on the eyeball.

Applications of the new material, greatly improving the quality of products. Plastic has the same high as glass, transparent, non-beating, weighs less, does not interact with the tissues of the eye, is harmless. Thanks to the excellent technological properties of the material made available new and more efficient methods of manufacturing lenses. Derfi extruded contact lenses.

Later Dallosom was discovered and widely spread method of turning. This method has been improved Obrigom in 1937. Methods of selection of lenses is also greatly improved. In 1938, Theodore Obrig proposed to assess the position of the lens on the eyeball to apply a solution of fluorescein, which is illuminated in blue fluoresce and allows us to estimate the thickness of podlinzovogo space in different areas of the lens. After that, the parameters corrected lenses.

Despite all the improvements, scleral lenses have many disadvantages - a lot of weight, large dimensions, stiffness in the eye, shortness of exchange podlinzovom tears in space, limited access of oxygen to the cornea. All these factors affect the tolerability of the lens and limits while wearing them. In addition, the process of selection and production of scleral lenses remained very costly, time consuming. Portability lenses failed to improve, or even using a PMMA using fenestration, special treatment to increase the oxygen in podlinzovoe space.

The search for more advanced types and designs of contact lenses continued. And in 1948, Kevin Tuohy (Kevin Tuohy) has offered to produce PMMA hard corneal contact lenses. They had a much smaller size than the scleral. And so the eye is not kept on for centuries, and by the forces of capillary attraction. Thus provide better access oxygen to the cornea - tolerability of contact lenses has increased by 2-3 times. If scleral lenses are able to carry 3-6 hours a day, corneal could be worn 10-12 hours.

The emergence of corneal contact lenses provided the impetus for the rapid development of contact lens - lens design and improved methods for their selection.

Improving form the inner surface of the lens was carried out as the study of the topography of the cornea. With the ophthalmometer, widespread technique, could be investigated corneal radius only in the central portion. F. Berg proposed a method topogometrii - ophthalmometer use to determine the parameters of the peripheral areas of the cornea. The method - measuring the radius of curvature of the cornea by different parts of the eye relative to the axis of rotation ophthalmometer.

But the possibility of simultaneous fixation and more accurate determination of the topography of the entire surface of the cornea appeared only after the establishment of the method fotokeratometrii. This method consists of photographic images corneal ring marks projected on the cornea. However, the difficulty of mathematical analysis of the fotokeratogramm caused limited application of this method.

There were other optical methods of measuring corneal topography: Profile photographing the cornea, measuring the gap between the lens with known parameters and the inner surface of the cornea, stereophotogrammetry methods of wave optics (interference and holographic), a method of "moire". Through research fotokeratometricheskim corneal topography were created contact lenses improved designs. Their inner surface is aspheric, that corresponds to a shape of the cornea. To correct astigmatism developed toric corneal lenses.

At the moment, for the selection of hard corneal contact lenses are two basic methods. The first - a very time consuming and therefore not widely used. This method is based on data about the shape of the cornea taken with precision keratometry. After removing the corneal parameters, calculated parameters of individual contact lens patient. After that, the lens produced on special precision lathe equipment. Widespread received the second method - selective. This method is based on the choice of lenses required special reference set. Help to simplify the procedure of selection of measurement Oftalmometres, refractometers and biomicroscopy. The trial consists of a set of lenses that differ in basic parameters: diameter, radius, asphericity diopter. All received during the selection data is entered into a special table. These calculated data are used for the manufacture of individual corneal contact lens.

The new stage of the development contact correction of vision began with the discovery in 1960 by Czechoslovak scientists Otto Wichterle (Otto Wichterle) and D. Lim of the new polymer material (HEMA) HEMA - a material that has the ability to absorb water. He becomes soft and flexible and allow oxygen.

Scientists have also developed a method of rotational polymerization, with which it was carried out the manufacture of soft contact lenses. The new material has good optical properties, so Dr. M. Dreyfus applied soft contact lenses for vision correction patients. At this time in the US was being developed optical systems such hydrogel based on acrylamide.

In 1981, the United States and Western Europe, there are lenses for extended wear.

In 1987, the first appearance of contact lenses to alter eye color.

In 1996, first appeared in the sale of lenses with a filter to protect the eyes from the effects of ultraviolet radiation.

The year 2000 marked the advent of the first contact lenses from silicone hydrogels of high permeability, designed for long-term continuous (up to 1 month without removing overnight) wear.