The
Development and Future of Contact Lenses
Reviewed
by Sylvester Yeo and Eric Sim
Yap
Shien Tah, 1st Year student,
School of Social Sciences, Singapore
Management University
Executive
Summary
The
development and proliferation of contact lenses has become increasingly evident
in the world today. Its capabilities has far exceeded what it once possessed.
This
paper will examine the history of contact lenses since the birth of its idea in
the 1500s, specifically why and how it was created. The paper then examines the
current state of contact lenses, the developments that have been made as well
as the effectiveness in achieving the purpose it was made for. In the process,
this paper will analyse the pervasive usage of contact lenses and the
divergence from its traditional purpose leading it to where it stands today. Finally,
this paper would seek to uncover the prospect of contact lenses. The future
considerations of where contact lenses is headed and how it would impact the
world would be explored. These considerations relate to the following aspects:
the functions of future contact lenses, socioeconomic effects, economic effects
and environmental effects.
1 Introduction
Since
a million years ago, mankind has begun developing technologies in all aspects
possible. The creation of fire, tools, weapons and machines were mostly geared
towards aiding humankind in what they did or do. Some innovators did venture
into the applications of knowledge on the human body. These were mainly medical aspects which
served to overcome diseases or sickness suffered by humans. Many of these
technologies served in prolonging the human lifespan, but there were a handful
which aimed at enhancing the human condition by correcting defects which
developed overtime. One such case was defects in human vision.
Ametropia
or better known as refractive error or in layman terms, image formation defects
is a common eye disorder suffered by humans. Refractive error takes place when
the eye is unable to focus clearly on the images from the outside world. This
would result in blurred vision, which could lead to visual impairment (WHO,
2013). The four most common refractive errors are myopia, hyperopia,
astigmatism and presbyopia (WHO, 2013). “Myopia (nearsightedness) is the difficulty
in seeing distant objects clearly. Hyperopia (farsightedness) is the difficulty
in seeing close objects clearly. Astigmatism is the distorted vision resulting
from an irregularly curved cornea, which is the clear covering of the eyeball. Lastly,
presbyopia leads to difficulty in reading or seeing at arm's length, it is
linked to ageing and occurs almost universally” (WHO, 2013). Although refractive
errors can be diagnosed and cured through means such as refractive surgery,
corrective glasses or contact lenses, but they cannot be prevented. (WHO, 2013).
WHO (2013) reports that an estimated 153 million people worldwide still live
with visual impairment caused by uncorrected refractive errors. This figure excludes
those suffering from uncorrected presbyopia, which is expected to be of a considerable
amount as shown by earlier evidence (WHO, 2013). A global estimate of 2.3
billion people suffer from poor vision due to refractive error (Thulasiraj, et
al., 2003).
Eyeglasses
and contact lenses are used mainly to correct refractive errors. They have been
used to correct the human vision for a long time. Eyeglasses have been invented
since 1285AD (Letocha and Dreyfus, 2002). However, it was not until 1508AD that
the idea of contact lens was conceived (Efron, 2010). Although the idea of the
contact lens was believed to be conceived in 1508, it was 380 years later
before the first pair of contact lens was actually fabricated and worn by
people.
A
contact lens is a thin lightweight apparatus that is placed precisely onto the
cornea of the eye. It is used in for corrective, cosmetic or therapeutic
purposes. Wearing contact lenses have various advantages, such as appearance
and practicality. Contact lenses provide a wider field of vision, are more
appropriate for numerous sporting activities and do not steam up as compared to
spectacles (Bedinghaus, 2009). There are generally two types of contact lens,
soft and rigid gas permeable (RGP) contact lens (FDA, 2013). These two
categories will be further explored in the historical section. Basically, they
differ according to their materials and purposes. As suggested by their names,
the soft lens has a softer texture while the RGP contact lens has a harder,
more rigid texture.
This
paper delves into the evolution of contact lenses over time. It examines the
historical rise of contact lens and how contact lens has developed since it was
invented. The current state of contact lens will then be covered, focusing on
its various purposes at present. At this point, the general inadequacies and
common drawbacks of contact lenses are examined. Subsequently, potential
developments of contact lenses are explored with the analysis on recent advancements
in this technology. Lastly, this paper forecasts and assesses the future
impacts that the potential developments of contact lenses would have on
society.
However,
this paper has its limitations such as the lack of use of statistical data to
illustrate the trends in the development of contact lenses. This can be
attributed to the dearth of resources and information made available to the
author. Furthermore, this paper could have explored in greater depth the future
issues that might arise and specific steps that could be taken to solve these
issues. Then again, to carry out an exhaustive evaluation on future issues and come
up with effective solutions would require not only additional resources but also
specialised knowledge in the forecasting of technology and strategic planning. Nonetheless,
with limited resources the author has provided this paper with insights,
analysis and evaluation to the best of his abilities.
2 Historical Perspective
Many
contact lens historians credited Leonardo da Vinci with illustrating and
sketching the first ideas for contact lenses in 1508 (Efron, 2010). They
believed that his book Codex of the Eye, Manual D, written in 1508, introduced
the optical principle underlying the contact lens (Efron, 2010). The underlying
principle was the alteration of corneal power. Indeed, Da Vinci did describe a technique
of directly neutralising corneal power, by submerging the head in a bowl of
water (figure 1). Yet, Da Vinci did not mention of any mechanism or device for rectifying
vision, instead the mechanisms of accommodation of the eye intrigued him (Heitz
and Enoch, 1987, as cited in Efron, 2010).
Years
after, a number of others illustrated theories in relation to the underlying
principle of directly altering corneal power. In 1636, Rene Descartes described
a glass fluid-filled tube which was to be placed in direct contact with the
cornea. Though it was aimed at altering corneal power, the theory was
impractical as it made blinking impossible (Efron, 2010). Then in 1801, Thomas
Young ran a series of experiments, constructing a device similar to the one
described by Descartes. He constructed a device that was essentially a
fluid-filled eyecup that fitted snugly into the orbital rim (Young, 1801). The
device was somewhat more practical in that it could be held in place with a
headband and blinking was possible, but the device was created with regards to
the mechanisms of accommodation and not for the correction of refractive errors
(Efron, 2010). Later in 1845, Sir John Herschel suggested two possible methods
of correcting critical cases of irregular cornea in the 1845 edition of Encyclopedia
Metropolitana. The first method was the application of a spherical capsule of
glass, filled with animal jelly, to the cornea, while the second method
consisted of impressing a mould of the cornea on some transparent medium
(Herschel, 1845, as cited in Efron, 2010). Although Herschel did not conduct
such experiments, his theories were adopted some 40 years later by inventors
unbeknown to each other and who were all apparently unaware of Herschel’s writings
(Efron, 2010).
During
the late 1880s, there was extensive research on contact lens which led to the
debate as to who first successfully fitted the contact lens. It was believed
that Adolf Eugene Fick, a German ophthalmologist working in Zurich, was the
first to illustrate the process of frabricating and fitting of the contact
lens. In 1888, he illustrated the fitting of a focal scleral contacts shells
first on rabbits, afterward on himself and lastly on a small group of volunteer
patients (Efron and Pearson, 1988). On the other hand, in 1889, August Muller
who was a student at Kiel University in Germany, was credited for the fitting
of the first powered contact lens. He managed to correct his own severe myopia
with a powered scleral contact lens (Efron, 2010).
From
1936 to 1974, further developments were made on contact lenses. These
developments involved the introduction of new materials of transparent plastic
(polymethyl methacrylate: PMMA), and silicone elastomer. Then after lenses were
separated into rigid or hard lens and soft lens. At that point of time, PMMA
was used to make rigid lens, while silicone elastomer was used for soft lens. Changes
in materials were due to limitations of each material, such as impermeability
to gases in PMMA and the hydrophobic surface of silicone elastomer. These
limitations have to be treated to allow effective and comfortable wear.
Eventually, they were solved with the introduction of new materials.
Advancement in technologies allowed incorporation of materials and for lenses
to be made from new materials. This allowed the previously impermeable to gas
nature of PMMA to transform into a permeable to gas nature. Substances such as
silicone, styrene and fluorine were incorporated into the rigid material of
PMMA for the transformation to occur (Efron, 2010). For the soft lens,
hydrophilic gels, specifically hydroxyethyl methacrylate (HEMA) was introduced
as a new substance used to manufacture lens (Efron, 2010). Its enhanced
biocompatibility and comfort, as compared to silicone elastomer, made it a
success. During this period,scleral lenses, which rest on parts of the sclera,
were also modified into relatively smaller corneal lenses, which covers only
the cornea (Efron, 2010).
Nevertheless
after the developments made in soft lens, patients still suffered from severe
eye reactions after prolong usage of the same pair of lenses. Lens deterioration
over time was a major impediment to successful long term lens wear. Moreover,
the high unit cost of lenses made regular lens replacements unfeasible.
Subsequently, a group of Danish clinicians and engineers, led by
ophthalmologist Michael Bay, developed a moulding process so that low-cost,
multiple individual lens packs could be produced (Mertz, 1997, as cited in
Efron, 2010). This product was known as Danalens. In 1988, Danalens’s packaging
system and moulding technology was further refined and the result was the
Acuvue lens. Acuvue lens is an inexpensive replacement extended-wear lens. Still,
the concept of contact lenses suffered from hypoxic lens-related problems, which
severely limited the clinical utility of contact lenses, especially for
extended wear (Efron, 2010).
A
decade later, silicone hydrogel lenses were introduced into the market. This
was a significant advancement in contact lens material technology, solving the long
frustrating problems related to hypoxic lens. Within a decade, all major
contact lens manufacturers have adopted the silicone hydrogel material and introduced
silicone hydrogel lenses (Efron, 2010).
It
can be seen that the developments of contact lens in the past were focused on
getting the right material for the manufacture of contact lenses. The materials
had to allow high oxygen permeability and be biocompatible with our eyes,
providing us comfort and safety. In addition, the main purpose of contact lens
was to correct the vision of our eyes by altering corneal power. These
developments served as a basic foundation for further advancements in contact
lenses which would introduce new purposes for the usage of contact lenses.
3 Current Situation
In
the year 2012, the number of people wearing contact lenses worldwide was an
estimated 125million. Contact lens wearers had an average age of 31 years old and
67% of wearers were female (NEI, 2012). Interestingly enough the current
purposes of contact lens are reflected in these statistics. In the present
world today, contact lenses are used for various purposes, not just for the
correcting of vision through altering corneal power anymore. This section will
explore the other forms of usage of contact lens, its therapeutic purposes and its
aesthetic purposes respectively.
3.1 Other Medical Purposes
Besides
correcting vision through the alteration of corneal power, currently contact
lenses are also used to meet other medical objectives, such as prevention or
delay of diseases and providing aid to people suffering from colour blindness. In
recent years, researchers have developed UV-blocking contact lens in a bid to
reduce UV radiation entering our eyes. One benefit of minimising UV radiation
to the eyes is lowering the risk of age-related macular degeneration.
Age-related macular degeneration is a major cause of severe vision loss for those
over the age of 55 (Johnson & Johnson Vision Care, Inc., 2012). Past
research have suggested that by maintaining higher levels of macular pigment, age-related
macular degeneration will be less likely to occur (Johnson & Johnson Vision
Care, Inc., 2012). According to a study presented at the 2012 British Contact
Lens Association Clinical Conference, UV-blocking contact lens has the ability
to maintain the eye’s macular pigment density (Johnson & Johnson Vision
Care, Inc., 2012). Hence UV-blocking contact lens could be used to delay
age-related macular degeneration. UV radiation could cause many other diseases
in eyes as well, the more common ones are photokeratitis – sunburn of the eye,
cataracts and cancer in the eyeball (Woerner, 2013). The use of sunglasses have
been able to protect the eyes from UV radiation, but UV-blocking contact lens
provides additional protection from this radiation. UV-blocking contact lens is
able to absorb UV radiation from coming from all angles, including angles not
covered by sunglasses. Moreover, these lens would provide all day UV
protection, as people would normally wear their contact lens throughout the day
as compared to sunglasses which are taken off when they are not needed. Furthermore,
scientist from the Institute for Bioengineering and Nanotechnology (IBN)
in Singapore have invented contact lenses that darken in the presence of
ultraviolet light (Scott, 2009). These contact lenses contain photochromic dyes
comprising of particles that change shape under UV light, hence becoming darker
which protects the eyes from UV rays (Scott, 2009). With the introduction of
UV-blocking contact lenses these eye diseases would be further prevented and
delayed in human beings.
Another
objective of contact lenses is to aid the colour blind. The X-Chrom lens, a
monocular corneal contact lens have been developed to do so. It significantly
enhances colour perception for those who suffer from the colour deficiency. For
instance, a colour blind person would wear a deep red tinted X-Chrom contact
lens in the nondominant eye in order to intensify the colour of red and green
(Art Optical Contact Lens, Inc., n.d.). One shortcoming, is that it does not
cure the vision problem of colour deficiency, but only facilitates better
colour differentiation.
3.2 Therapeutic Purpose
Therapeutic
purposes can also be linked to medical usage of contact lenses. Therapeutic
usage of contact lens include bandage contact lens and contact lens that
deliver drugs to the eye. When people suffer from corneal damage due to eye
disease or injury bandage contact lenses are used to promote healing and reduce
discomfort. They protect the eye from external assault and also isolate the
corneal surface from friction during blinking (Trattler, n.d.). Bandage contact
lenses are also used after eye surgery, as they allow for easy installation of
medication as compared to other protective barriers. Additionally, they act as
a reservoir for medications, increasing the amount of time the medication stays
in contact with the eye (Trattler, n.d.). Eye drops are said to be inefficient because
an estimated of only 7 percent of the eye drop medication is actually absorbed
into the eye (Leggett, 2009). The other 93 percent flows out of the eye and
drips down the cheeks. More often than not, patients tend to forget or avoid
taking their eye drop medications as it is a hassle. Nonetheless, eye drops
still account for 90 percent of all eye medication (Leggett, 2009). Drug-dispensing
contact lenses serve to solve these problems. Recently, researchers have
created contact lenses that are able to dispense a high concentration of
antibiotic at regular rate for more than 30 days (Leggett, 2009). The drug
containing portion of the lens is shaped like a doughnut so that it would not
affect the wearer’s vision (Figure 2) (Leggett, 2009). With this invention,
many eye related medication can be replaced or complemented with it.
3.3 Cosmetic Purposes
The
rise of cosmetic contact lenses is becoming increasingly prominent. Nowadays,
contact lens wearers tend to purchase tinted contact lenses to beautify
themselves. Even people who need not wear contact lens do purchase zero-powered
cosmetic contact lenses for aesthetic purposes. Cosmetic lenses can be
customised to individualise look or enhance performance. Cosmetic contact
lenses are effective in changing eye colour and appearance. They may be used in
several therapeutic applications such as masking disfigured eyes (The British
Contact Lens Association, n.d.). Other applications involve personal grooming,
the movie making industry and professional athletes. In the sports sector,
colour tinted lenses are used to increase visual performance. These lenses reduce
glare, enhance contrast sensitivity and heighten depth perception. For example,
a green tint lens can enable a tennis player to see the ball more clearly on
the court (Surtenich, 2013).
On
another note, an Indian optometrist has went a step further in making contact
lens as an accessory. Chandrashekhar Chawan invented the world’s first pair of
contact lens embedded with gold and diamonds (Figure 3) (Scott, 2011). The lens
is designed in such a way that it can be customised to correct any visual
impairment and would not stop the eye from receiving oxygen (Scott, 2011). It
is also said to be comfortable to wear, with the lens being able to retain
water in front of the cornea to ease the eye (Scott, 2011).
3.4 Limitations
Generally,
contact lens pose a serious threat to the eyes without proper use and
supervision. Contact lenses can cause eye irritations or infections, if not
treated in time it could lead to blindness. For example, fungal eye infection
is possible with the usage of contact lenses. This condition can lead to
blindness and include symptoms like increased sensitivity to light, pain or
redness, blurry vision and excessive discharge from the eye (NBC News, 2006).
Swimming
with contact lens is also a danger. In fact, the United States Food and Drug
Administration recommends that contact lenses should not be exposed to any kind
of water, including water in swimming pools, showers and tap water (Surtenich,
2012). This is because water could be home to countless of viruses and
dangerous microbes, which could potentially infect the eye and cause blindness.
In order to minimize chances of such conditions contact lens users should maintain
high hygiene standards, follow medical advises and seek regular medical
checkups from their eye doctor.
Contact
lenses are also not made readily available globally. As the usage of contact
lens requires supervision by professionals and certain technologies to do so,
less developed countries often have little or minimal availability of contact
lenses. Some contact lenses can also be quite costly itself. Even if more
affordable contact lenses such as cosmetic lens are made available to less
developed countries, professionals and proper eye care material would be needed
to educate and facilitate the usage of lenses. Hence, the current distribution
of contact lenses is limited to the more affluent societies and less developed
societies are unable to utilise this technology. Although, one may argue that
it is not needed to be made globally available as less affluent societies are
not able to afford this technology, contact lenses serves to improve the lives
of people, not just rich people. The author proposes that if the use of contact
lens could be made available globally, it should, due to its benefits and the
potential it holds.
4 Future Considerations
Projecting
into the future, the acceleration in the development of contact lenses could
herald an age of revolutionary change. There are immense amount of
possibilities with research and innovation being done on an equipment the size
of a fingertip. Contact lenses could literally change the vision of the whole
world. This section examines the considerations which the author believes might
arise in the future if contact lenses were to be further developed and adopted
on a massive scale.
4.1 Lenses of the Future
The
possibility of having bionic eyes with the ability to zoom in on a distant
object and project virtual displays seem surreal. Yet, for the first time a
group of engineers at University of Washington have invented a biologically
safe contact lens with lights and an imprinted electronic circuit (Figure 4) (Moskowitz,
2008). A completed lens was said to have the display superimposed on the
outside world. The engineers tested the lenses on rabbits and no adverse
effects were shown by the animals (Moskowitz, 2008).
The
lens served as a step towards the development of bionic lens in the future,
showing that the idea is feasible. If bionic lenses are indeed created in the
future, it would yield a plethora of possibilities. The author believes that
the successful innovation of this technology in the future would simplify
processes by incorporating various purposes into it. People no longer have to
carry around communication devices or even a laptop, the functions would be
projected on a midair virtual display screen that only the user would be able
to view. Of course this would require the combination of several technologies,
maybe even some which are not in the market yet. The army could utilise the
lenses to simulate training, in turn reducing the resources needed for trainings.
Perhaps, drivers could even see their route plotted on their contact lenses. At
that point of time the use of Google Glasses would be irrelevant being
superseded by the advantages of lenses. The future could be a time where
contact lenses exerts its dominance globally, where owning a pair of lenses
becomes a necessity.
Contact
lenses of the future might also eliminate or at least significantly reduce the
occurrences of many eye diseases. Presently, contact lenses already do so much
in the medical field as elaborated earlier in the previous sections. All the
more, in the future advance developments would be made and contact lenses could
aid those visually impaired, possibly helping them gain some sight. In
addition, it could help detect eye diseases early on without the need to visit
the doctor. For example, the lenses could be designed to observe eye conditions
and identify irregularities, so eye disease like glaucoma which symptoms do not
normally appear early on can be detected earlier on and treated before the dire
effects takes its toll on the person.
4.2 Socioeconomic Effects
The
author believes that another future consideration on the development of contact
lens would be the socioeconomic impact on the world. The prices of contact lenses
of the future might bring about significant inequality worldwide.
Currently,
not all types of lenses are at affordable prices. For example, orthokeratology
lens which corrects refractive errors of the eye costs a few hundred dollars per
piece. Furthermore, the price of purchasing a technology similar to bionic
lenses, the Google Glasses, presently costs US$1,500 per pair. With the use of
advanced technologies and intricate manufacturing process, the price of bionic
lenses in the future would be considered astronomical by the less affluent. The
author submits a scenario that future contact lenses, such as the bionic
contact lens, could be made a product which marks or exemplifies the social
status of the more affluent. Now, products like apparels and accessories are
already being used to symbolise the status of the rich. In the future, contact
lens companies could control the price or distribution of bionic lens making it
exclusively available only to those who can afford or deserve it. Hence, only
the rich and powerful could utilise this particular technology, while the rest
would be at a disadvantaged lacking the technology and possibilities it could
bring.
On
the other hand, overtime with the advancement of technologies, the
manufacturing process might be made more efficient and simplified, leading to a
reduction in cost. Moreover, governments can implement policies to promote competition
in the contact lens industry, which encourages technology advancement and
reducing cost at the same time. Governments can also offer subsidies when the
need for the possession of contact lens is of great importance. Therefore,
there might come a time when future lenses are made affordable even to the less
affluent. This would allow people of all financial status to utilise the
available technology.
4.3 Economic Effects
The
author believes that with the imminent rise of the functions of the contact
lens, the contact lens industry could be expanded and evolved. As of 2012, an
estimated of only 125 million out of 7 billion people in the world wear contact
lenses (NEI, 2012). If every person in the world wore contact lens the market
would be expanded by 56 times. In the future, the market of contact lens is
bound to be even larger, as the population of the world continues to grow. This
could lead to various economic benefits.
In
the future, with a substantial increase in functions of contact lenses its use
would be made more relevant to the world. The author depicts that if contact
lenses do one day replace communication devices, maybe even some electronic
devices, the use of contact lens would be necessary for all. The market of
contact lenses would be collaborated with all other communication devices and
electronic devices, possibly making it one of the biggest industries in the
world. In addition, the product could have so many variations that it could
evolve into an industry similar to the phone industry. Contact lenses could be
classified into different types and models, with companies competing to produce
better models into the market. The expansion of the contact lens industry, would
create countless of jobs and increase trade globally. With a considerable
amount of economic activities originating from contact lenses, it could be one
of the drivers of economic progress in countries. Still, if this technology is
being monopolised it could hinder its economic progress and instead benefit
only the organisation controlling the technology.
4.4 Environmental Effects
If
contact lenses do live up to its expectations, the author submits that contact
lenses could have positive environmental impacts in the long run. However, in
the short run it might worsen environmental situations. Contact lenses of the
future could help reduce the amount of waste produced and resources used.
Waste
production is an ever increasing problem, especially in developed countries. In
Singapore alone, the amount of waste produced in 2012 was 7.3 million tonnes up
from 4.7 million tonnes in 2000 (Tay, 2013). As countries become more
developed, the amount of waste tends to increase. This is because as countries
develop people get more affluent and are able to afford more resources, hence
the consumption of products increases in turn leading to a rise in waste produced.
With the introduction of contact lenses of the future, several products will
become negligible. As previously mentioned, products such as laptops and
communication devices could be replaced by the advanced technology of contact
lenses. In addition, as the functions of contact lenses multiply resources used
for training and therapy could also turn insignificant. In the short run, after
the introduction of contact lenses of the future the amount of waste might
increase by a significant amount as people globally start to get rid of these
common products. Yet, in the long run the amount of waste produced would be
decreased as these products are being replaced. People no longer need to
constantly buy electronic products to replace their old or spoilt ones.
The
replacement of products could also lead to a reduction in the consumption of
resources. The author proposes that with more and more products getting
replaced by contact lenses, the production of those products would decline
drastically or even come to a stop. Consequently, lesser resources are used and
the worldwide usage of energy resources would be reduced. The development of
contact lenses could serve as one of the factors bringing about a sustainable
future as it develops into a “many-in-one” product.
5 Conclusion
This paper has examined the transformation of contact lens overtime. The original concept and purpose of contact lens served as a foundation for this finger-tip sized technology.
The
advancement in technology has amplified its capabilities and made contact
lenses safer to wear. Though there are limitations to the uses of contact lens,
many still utilise it and future developments could possibly solve them. The
author believes that humankind has only scrapped the surface of potential of
contact lenses. Contact lens could one day be the dominant technology of the
world.
The
future considerations mentioned in this paper are salient factors which should
be addressed. Addressing these factors would steer the industry of contact lenses
in the right direction, maximising its potential benefits. If left unaddressed
contact lenses could amplify the effects of current issues such as social and
economic inequalities. Contact lenses have the potential to change the entire
landscape of virtual technology and even more. With comprehensive research and
development on contact lenses, it could herald an age of revolutionary change,
changing the vision of the world literally.
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