Risk Factors of Using Contact Lenses
Around three months ago, a young lady from
Texas, Amy, visited an optometrist to get her newly bought contact
lenses fitted with no clue of what was to come. This is a common task
performed by many lens users. After using them for a few days, she
started to feel immense pain in her left eye. At first, she thought it
might be dirt that got in. However, as the pain persisted, she was
referred to the hospital where it was identified that she had a corneal
abscess. An infection had caused a purulent ulcer in the transparent
corneal tissue that may result in long-term visual impairment and
permanent scarring.
Even though the patient was provided with the necessary care, due to an
underlying fungal infection in her eye, she had to undergo a corneal
transplant. The medicines meant to prevent the fungus from spreading in
the cornea were ineffective, and the doctors had to remove it. This case
is quite rare, but it is not the only one: contact lenses bring a great
deal of beauty and comfort, but they can also cause a range of problems
that can negatively affect the wearer's quality of life. So, what are
the usual hazards associated with contact lenses?
To fully comprehend the danger to the eye
posed by contact lenses, one must first know what a cornea is. The
cornea is a transparent dome-shaped tissue that envelops the front part
of the eye and partners with the eye’s lens (which is likewise
transparent) in the process of refraction. Damage to the transparent
corneal tissue, which will appear as cloudiness of the cornea, will
cause the light beams that are transmitted to the retina to be
distorted. This will result in a blurred image. Additionally, any harm
to the symmetrical structure of the cornea will cause vision damage.
Dr. David Sorkin, who studies the cornea, emphasizes the potential
danger of corneal abscesses - a type of infection that commonly occurs
with the insertion of a foreign body or contact lenses. He explains that
this infection is often caused by the inappropriate use of disposable
lenses or sleeping with lenses in, leading to redness and blurred
vision. If the abscess is left untreated or does not respond to
medications, it may create permanent scarring in the transparent corneal
tissue, clouding it and damaging its structure. This may result in
impaired vision. Furthermore, the amoebae can attach to the front
surface of the lens.
Peter Stils from Chicago also used to wear contact lenses. A few months
ago, he was referred to a hospital where he was diagnosed with a severe
corneal infection caused by a parasite, an amoeba called Acanthamba.
"Due to visual impairment, I used contact lenses regularly. One weekend,
I woke up with a red and painful eye. I was referred to the emergency
room, where I was diagnosed with a corneal abrasion. I was given an
ointment for treatment and an appointment for a follow-up examination
after a few days. The condition of the eye did not improve, and an
infection called Acanthamoeba was detected during the inspection," he
says.
In his case, as in many other cases, the serious infection was caused by
a parasite found in water sources. This parasite is resistant to most
ingredients in contact lens solutions. "I didn't make sure to wash my
hands before taking them out and putting in the lenses," said Daniel,
revealing in fact the sensitivity of lenses to infections originating
from the palm of the hand.
red eye from infection.
Dr. Roy Daniels, an expert in ocular
diseases, emphasizes that multiple examinations affirm a relationship
between using tap water and the emergence of Acanthamoeba on rigid
contact lenses. He further attests that a plethora of studies also
demonstrate that cartridges are a breeding ground for bacteria and
microorganisms. The researchers caution that cleaning the cartridge with
unclean tap water increases the likelihood of the amoeba attaching to
the lens. Eye irritation is a worrying side effect - and this is yet
another straightforward example.
Many people who wear contact lenses
mistakenly think that using water to clean and prep the lenses is okay.
However, this is not a good idea. Even though the water may be safe to
drink, it is not sterile and contains microbes. These can be absorbed by
the lenses and may cause breaks in the cornea. This can lead to
inflammation and infection. Additionally, the lenses can swell as they
absorb the water, which may cause them to stick to the eye and cause
discomfort. For this reason, it is not recommended to shower or swim
with contact lenses. Furthermore, there is a risk that the lenses will
be lost in the water. Therefore, it is important not to use water to
treat soft contact lenses in any way.
People who wear contact lenses sometimes worry that they will get stuck
behind the eye. Fortunately, we're happy to report this is impossible
since the conjunctiva (the sclera) and the inside of the eyelids are
protected by a thin membrane. However, soft lenses can sometimes fold
and become lodged under the upper eyelid, resulting in discomfort and
requiring a visit to an optometrist or an ophthalmologist to remove it.
An allergy to contact lenses refers to a sensitivity of the eyelids to
the accumulation of proteins and antigens on the surface of the lens so
that when you blink, contact is made between the eyelids and the
proteins, and an allergic reaction is obtained that makes it difficult
or impossible to assemble the lenses. An allergic reaction to contact
lenses can manifest itself in watery or red eyes, an itchy feeling,
blurred vision, pain, tingling, runny nose, edema, and the like. Reality
shows that more than once, an allergic reaction to a certain type of
lens occurs.
For example, there are people who are only sensitive to soft lenses or
hard lenses. Others are sensitive to lenses only after wearing the same
pair for a long time. In the event that an allergic reaction develops,
immediately stop using the contact lenses and consult an ophthalmologist
or optometrist. Often a certain pause will be required, after which it
will be necessary to change the type of lenses or find another solution.
In the case of a mild allergy, it may be possible to continue wearing
the lenses.
Not just infection, but also filth
It appears that this product only poses a
risk to eye health. However, a study revealed that 20 percent of
disposable lenses are discarded of improperly, either by being thrown
down the sink or toilet and entering a wastewater treatment facility.
Even though there are various types of daily lenses, the polymers
(plastic molecules) they are composed of are not degraded by the
treatments within the facility. As a result, the lenses stay in the
emissions of the facility, becoming microplastic pieces that pollute
both terrestrial and aquatic habitats.
Up until now, there is no widely-available or successful method of
treating wastewater that contains polymers used to make contact lenses.
Furthermore, the amount of waste that defective contact lenses produce
is much greater than most people realize. Each year, the United States
uses 14 billion contact lenses, which yields 20 tons of non-processed
plastic and 14 thousand tons of plastic packaging. Plus, the aluminum
coating of the packaging is also discarded, corresponding to the same
amount as 19 million beverage cans.