In this era, many of us wear contact lenses. It might be for several reasons, either for vision, aesthetic purposes, or comfort. The number of contact lens wearers is 140 million globally!¹⁰ In this article, let's explore how contact lenses cause eye inflammation and what the best measures are to prevent it.

What do you mean by keratoconjunctivitis?

Keratoconjunctivitis is a condition where both the outer layer of cornea and the conjunctiva are inflamed. Inflammation of the cornea is known as “Keratitis,” and inflammation of the conjunctiva is known as “Conjunctivitis.¹ The conjunctiva is a clear, thin mucous membrane covering the sclera and lining the inner part of the eyelid. The part covering the white of the eye is known as the bulbar conjunctiva, and which covers the inside of the eye is known as the palpebral conjunctiva.

How is wearing contact lenses related to keratoconjunctivitis?

Contact lenses are useful for eyesight but have several risks. Wearing it continuously results in a higher degree of corneal inflammation. If the contact lens is worn too long and if we do not take the correct measures, then a virus, bacteria, fungi or parasite might invade our eye and lead to microbial keratitis.²

Infection of the eye is severe with microbial keratitis. Therefore, it has to be treated and diagnosed quickly. It is considered an important public health issue as it causes severe problems.⁴ For example, in the United States, contact lenses are the greatest risk factor for microbial keratitis. There has been a 55% increase in the late 1990s from 0% in the 1950s. 

There is also a study that relates to people in Germany.⁵ It confirms that wearing contact lenses without proper hygiene causes a risk of microbial keratitis. This leads to discomfort and eye problems. Ninety percent of cases are caused by bacteria, and less common causes are from acanthamoeba and fungi. These pathogens contact the surface of the eyes with a contact lens and can penetrate the corneal tissue. This changes the corneal epithelial tissue, and if this is detected early, then it is cured without medicine. In case of advanced bacterial infiltration, strong antibiotics are required. Emergency corneal transplantation is done in severe cases.

The main cause of contact lens-related keratoconjunctivitis in Europe is bacteria. The percentage of cases affected is 91 to 100%, through fungi are 3-7%, and acanthamoeba is 1-5%.⁵

What could be the reasons for eye infections from contact lenses?

Various reasons cause contact lens-related keratoconjunctivitis. They might result from a short span or might have been there for a longer duration. The severity might be minimal, or it might damage the sight permanently.

Mechanical factors— The eyes get irritated or abraded due to the improper design of the contact lens. This might be due to improper fit or obstruction from foreign agents like dust or various other particles. It might also occur when there is an alteration in the pressure from decompression or acceleration.

Physiological factors— The response of the eyes to decreased oxygen levels at high altitudes leads to infection. This includes the usage of preservatives in lens care solutions.

Immunological factors, like allergies, which result in low tolerance to contact lenses.

When there is a disruption of the tear film, it leads to improper function of waste product removal. Therefore, there will be alterations in the removal of foreign particles, lubrication, and in preventing the eyes from drying.

Many are susceptible to contact lens-related papillary conjunctivitis. These cases are more commonly observed with the use of soft lenses(silicone hydrogel lenses).

What are the risk factors that develop keratoconjunctivitis in contact lens wearers?

Risk increases three to four times for the following habits. 

• If they prolong the wear of contact lenses for a longer time and keep them overnight
• In case of improper hygiene measures, like not washing their hands, and swimming with their contact lenses
• They have a habit of smoking and have very little experience in handling contact lenses
• Lower socioeconomic status is also a contributing risk factor
• Patients who order contact lenses online do not see objects up close and tend to have an increased risk of developing keratoconjunctivitis⁵

The usage of soft lenses, mainly silicone hydrogel lenses, is known to be a risk factor for contact lens-linked papillary conjunctivitis. Itching, redness, inflammation of the upper palpebral conjunctiva, and discharge of mucus are observed in eyes.⁸

The main reason for contact wearers is discomfort and dryness. Around fifty percent of users experience dry eye symptoms, suggestive of dry eye infection.⁸

How can we know that our eyes are infected from contact lenses?

Our eyes respond in various ways when they are infected. A few of the symptoms are:

Blurred vision, unusual redness in the eyes, tenderness or pain in the eye, excessive tears or discharge of mucus or pus from the affected eye. Eyes are more sensitive to light.

It feels like there is something in the eye, although there might be nothing in the eye.⁷

Prevention strategies

We should take extra precautions with contact lenses to avoid eye infection. Regular lifestyle habits, the supplies we use, and our eye care provider all play an important role in keeping our eyes healthy without eye complications.

The foremost step is to avoid sleeping with lenses and follow the directions of the eye care provider. Our hands have to be washed thoroughly with soap and water and dried with a tidy cloth before touching the lenses.

Contact lenses should not contact with water; we have to remove them before taking a shower and swimming so that they prevent germ exposure.

It is recommended to clean our contact lenses with the contact lens solution. Rubbing and rinsing with disinfectant solution and making sure not to mix fresh and old solutions from the case are mandatory procedures to follow.

All required steps have to be followed to care for our contact lens case. It's advised to clean the case by rubbing and rinsing with the solution. The case has to be stored with caps off and turned upside down. The case is required to be replaced once every three months.

Whenever there are concerns that require attention regarding the wear and care, then it has to be discussed with the eye care provider. Regular annual eye checkups are recommended. In case there is discomfort in your eyes with the lenses, they have to be removed immediately.⁹

FAQ’S

What are the different conditions that impair the eyes?

Injuries, Allergies, Keratitis, Dry eye, and Dystrophies of the cornea are a few conditions that impair the ability of the eye.

What are the main reasons for contact lens-associated eye infection?

Improper eye care and non-maintenance of contact lenses lead to eye conditions like Keratitis.

What are the initial steps to take care of when we have conjunctivitis from contact lenses?

Stop wearing contact lenses for a few weeks, and reduce the duration of time you wear contact lenses on a daily basis.

Contact the ophthalmologist in case of emergency.

How long does it take for conjunctivitis to resolve?

It takes about 7-10 days for a few people, but many require antibiotic treatment for about 7- 10 days.

Which types of bacteria are mainly associated with contact lenses?

Pseudomonas aeruginosa and Staphylococcus aureus are the two main types associated with contact lens keratitis.

Why do I suffer from conjunctivitis repeatedly?

When conjunctivitis repeats several times, it's best to visit an ophthalmologist. It might be due to various reasons, like allergies, irritants, poor maintenance of contact lenses, or any related medical condition.

What are corneal ulcers?

It is also known as keratitis. Corneal ulcer is a more serious infectious condition of the cornea that requires immediate treatment and should not be neglected.

What is corneal molding?

It refers to an alteration in the shape of the cornea due to wearing contact lenses.

What is giant papillary conjunctivitis?

It is usually seen in soft contact wearers who follow extended wear schedules and is a common complication. 

What is meibomitis?

It is due to the diminished function of the meibomian glands. Meibomian glands are seen in both upper and lower eyelids, which secrete oil that is a main constituent of the tear film on the cornea.

Summary

Contact lenses are used for different purposes by all of us. It might be for correcting our vision, for aesthetic, or comfort. We should be very careful in handling and maintaining the contact lenses. It is always advised to follow healthy habits, strategies to take care of our eyes with contact lenses. Otherwise, we are prone to keratitis and conjunctivitis. When diagnosed with keratoconjunctivitis, we should not neglect it. We must avoid wearing our contacts for a few weeks and get a thorough check-up with our eye care provider at the earliest.