A Tribute to the Father of the Soft Contact Lens
This compelling feature pays tribute to Otto Wichterle and includes excerpts from his auto-biography, Recollection.
By Loretta B. Szczotka, O.D., M.S.
Almost 40 years ago, Professor Otto Wichterle developed the first hydrogel contact lens in Prague, Czechoslovakia. This Czech chemist, who died on August 28, 1998, at the age of 84, is the scientist responsible for developing a hydrophilic polymer for contact lens use. It's amazing that the material chemistry of the first HEMA contact lens has seen little change in the last 30 years. But just after his death, major changes in the soft lens industry occurred in the worldwide market with the introduction of silicone-hydrogel contact lenses. These lenses combine the biocompatibility, comfort and optics that Dr. Wichterle first imagined and achieved years ago, but now also include a significantly greater oxygen transmissibility.
In October 1998 at the European Research Symposium (ERS) in Prague, the late Professor Wichterle was remembered for his achievements as the "father of the soft contact lens." As Carl Sassano, President of Bausch & Lomb Vision Care, said at the ERS, "His remarkable research, dedication and vision revolutionized our profession forever." During the ERS presentations, it was amazing to see how the contact lens industry has come full circle since Dr. Wichterle's original invention.
Bausch & Lomb returned to Prague, the birthplace of the soft contact lens, to introduce one of the next- generation silicone-hydrogel lenses, unveiling their first high-Dk soft lens.
Dr. Wichterle was urged to write his autobiography, Recollection, in 1994. The following excerpts from that book give us insight into the work of this great pioneer in our field, and into his development of a product that has been revolutionary in many of our contact lens practices.
The book was described well by Mr. Miroslav Holub from the Times Literary Supplement in 1990: "Otto Wichterle's autobiography will appear in Prague before long. It is a drily and soberly narrated story of the life of a Czech chemist, inventor of the polyamide fibre and of the soft contact lens; it is at the same time, a history of Czech steadfastness and pragmatism whatever the circumstance and during all the occupations of the past 55 years."
Dr. Wichterle began describing how his interest in the ophthalmic field began almost 50 years ago: "In the summer of 1952, on the express train from Olomouc to Prague, I sat next to a man who was reading an ophthalmology magazine. I came up with the suggestion of using slightly cross-linked hydrophilic three-dimensional polymers with which better compatibility (than metal, for a prosthesis as a substitution for enucleated bulbs) could be expected. I liked the idea of water-swellable gels so much that I filed a patent and described in detail all of the possible applications of these gels, mainly in medicine, though also in the production of contact lenses, which were purely fantasy at that time."
Achieving Your Potential
Dr. Wichterle quickly realized the potential of applying his ideas, and began working on developing a hydrophilic polymer. "In equilibrium with water, the poly-hydroxy-ethylmethacrylate gel (poly-HEMA-gel) contained about 40 percent water. Its mechanical properties were rather good, and it was even perfectly transparent. It was then necessary to give this gel the precise shape of a contact lens."
His initial attempts at producing these lenses began with using closed polystyrene molds and polymerizing an aqueous monomer solution. The main difficulty with this process was the resulting irregular lens edges, and the tearing of the gels when the forms were opened. "Besides damaged lenses, however, I was able to occasionally find one which was quite good, and at the end of April 1957, I finally put it on my eye. It was a thick plus lens, allowing me to easily find a near distance which I could see sharply. The lens irritated me considerably with its edges, but those few minutes in which I could stand it were enough to recognize that soft gel lenses could certainly be used for correcting vision."
In 1958, technical research into hydrogel lenses and hydrophilic gels at Prague University was halted, and Dr. Wichterle was expelled. However, his research continued at the Czecholslovak Academy of Sciences, where he was subsequently placed into the Institute of Macromolecular Chemistry.
In 1961, Dr. Wichterle's latest idea was to cast lenses in open, rotating forms. With glass molds, a mechano set and a generator from his son's bike, he constructed a casting device on Christmas Eve 1961. "On Christmas afternoon, I put the device into operation and cast the first four lenses with very regular edges." The next day, he applied these lenses to the eyes of hospitalized patients at a local ophthalmology clinic. "We applied lenses to their healthy eyes and it did not cause any irritation at all. But the patients were not able to see anything because the lenses had very high refraction. These lenses could, however, be perfectly corrected with spectacles, which proved that even their optical qualities were good."
Dr. Wichterle continued to improve his prototype casting device. "By New Year's Eve, I had already built the device with 15 axes, but the bicycle generator was not strong enough, so I had to get a stronger engine. I did this by gutting my gramophone set. In a week, we (he and his wife) were able to produce several hundred lenses, and in the first four months of 1962, we produced 5,500 lenses."
To maximize the equilibrium content of water in a swollen gel, the first several hundred lenses were produced from a mixture consisting of 80 percent hydroxyethyl-methacrylate (HEMA) and 20 percent diethylenglycol-methacrylate (DEGMA). However, Dr. Wichterle thought that those gels had diminished mechanical resistance, so he began producing these lenses from pure HEMA. He goes on to mention, "It's interesting that after about 30 years, we came back to the highly hydrophilic copolymer HEMA-DEGMA."
In 1963, Dr. Wichterle met George Nissel, the most famous producer of hard lenses and lathing instruments of the time. Nissel told him how great it would be if hydrogels could be shaped on similar lathing machines. This gave Dr. Wichterle the idea of producing the poly-HEMA without solvent, turning it on a lathe, and later, swelling it with water while it maintained its optics. He quickly patented this material and technique and called it "xerogel."
Turning his invention into a large-scale production was the next step. In 1964, the first serious interest in a large-scale application of his patents came from American brokers, Martin Pollack and Jerry Feldman, who operated the National Patent Development Corporation (NPDC). Pollack recalled his first interaction with Professor Wichterle:
"I first met Professor Wichterle on a visit to Prague in 1964. I was returning to New York from Moscow when I was alerted by my partner, Jerry Feldman, that a Czech chemist had invented a new contact lens. The lens, made from hydrophilic polymer, would prove to be a revolutionary breakthrough in eye care and earn the inventor a distinguished place in polymer chemistry.
My company, the National Patent Development Corporation, helped the Institute of Macromolecular Chemistry and Professor Wichterle make some modifications in his production method. We licensed the soft contact lens technology and subsequently, sublicensed it to half a dozen companies throughout the United States and Europe. We, ourselves, set up a company and manufactured and sold soft lenses in the United States, Canada, Australia, Japan, China, the U.K., Spain, Italy and Holland. This venture became a billion dollar national business for hydrophilic contact lenses and accessories."
In 1966, Pollack concluded an agreement with Bausch & Lomb (B&L), a prospective producer and sublicense partner, who later assumed the financial obligation of the NPDC. Dr. Wichterle described this partnership in the following manner: "The choice of Bausch & Lomb as the sublicense partner had many advantages. It was a strong company with large capital, modern equipment and excellent personnel, and was able to produce even very complicated devices, such as infrared spectrometers, and a whole set of devices for optics. It was very advantageous, too, that the company had never before produced contact lenses, it being, therefore, free from conservative clinging to hard contact lenses, which was typical for their producers."
In the following years, B&L invested about $3 million annually in creating a large distribution network, the further refinement of Professor Wichterle's machines and physiological tests of the products, which were required by the FDA. In March 1971, the FDA finally issued approval for the distribution of the lenses. Dr. Wichterle remembered that, "The stock exchange reaction was fantastic. Almost from one day to the next, the value of B&L's shares increased from $47 to $150. The share capital of the company had increased by $250 million in one day."
Since that day, the soft contact lens has seen many revisions. But perhaps, none has been dramatic as the recent development of silicone-hydrogel contact lenses. Only time will tell what other future advancements will expand upon Dr. Wichterle's original invention. CLS
A special thank you to Joe B. Goldberg, O.D. for the letter that is illustrated in this article.
"Recollection" was translated by Dr. Blazena Kukulisova, revised by Kevin Dalrymple and printed by Ideu Repro, Prague.
Dr. Szczotka is an assistant professor at the Case Western Reserve University Department of Ophthalmology and Director of the Contact Lens Service at University Hospitals of Cleveland.
Dr. Wichterle at his 80th birthday celebration.
Czechoslovak Academy of Science Institute of Macromolecular Chemistry Praha 6, Czechoslovakia
July 1st, 1964
Joe B. Goldberg, O.D.
Conforma Laboratories, Inc.
4700 Colley Avenue
Many thanks for your letter of June 11, 1964. Enclosed you will find some samples of our lenses and the basic information about their application. We have noted your address, and as soon as the lenses are introduced into regular distribution, we shall let you know.
Prof. O. Wichterle
The samples of lenses represent different values of refractive power. The inner curve of these lenses is parabolic in all cases. The central radius of the parabolic curve varies in the range between about 7.5 and 9.0. It is possible to apply the lenses practically without respect to this radius because of the softness of the lens and its adaptability to the corneal curve. Only in extreme cases of differences (e.g., if the lens is very flat in comparison with the cornea), the lens is not well centered and moves easily in the eye and is to be replaced by a steeper one.
Before applying, these lenses are to be maintained at least one day whether in physiological saline solution or in a solution of 0.5 percent sodium chloride and 0.5 percent sodium bicarbonate in distilled water. The latter we consider to be more convenient because of its ability to fix not only the osmotic equilibrium, but also the neutral reaction of the gel.
The use of antiseptics for sterilizing the lenses is not recommended, as the antiseptic penetrates very easily into the lens and produces a long-term irritation after the application. On the other hand, a very simple and generally applicable way of sterilizing consists in heating the lens for several minutes at about 100 degrees C. If the lens is heated in the physiological solution, no alteration or change in shape and composition occurs not even after many hours of heating. A periodical sterilization of lenses (every two weeks at least) is recommended to prevent growth of microorganisms inside of the lenses. The development of microorganisms in the lenses is without any harm for the patients but it impairs the lenses. The insertion of the lenses is similar to the way used with normal hard lenses. The removal of the lenses is somewhat different: it is necessary to press the lens between two dry finger tips against the eyeball and by folding it, enable air to penetrate below the lens.
A new feature in the adaptation procedure is given by the possibility of shifting the lens to the lateral position. The soft lens is adapted in this position to the flatter scleral curve without producing pain. The patient's cornea can have a rest during this eccentric position without the rather complicated and embarrassing withdrawing from the eye. This procedure is applied, e.g. after the patient has observed the formation of Sattler's weil. Recentering can be achieved by pressing the closed eye from the side.
Prof. O. Wichterle