Photokeratitis - Causes, Symptoms, Diagnosis, Prevention, and Treatment

Introduction:

Photokeratitis is an eye condition that results from direct exposure to ultraviolet light. It is also known as photoallergic contact dermatitis, which occurs when the eyes are exposed to an allergen such as sunlight or other ultraviolet light rays.

The condition is similar to sunburn except that it affects the eye's corneal surface. It is a temporary yet painful condition that may last a few hours to a few days.

What Is Photokeratitis?

Photokeratitis is a condition in which a person experiences temporary eye symptoms on exposure to sunlight or UV (ultraviolet rays). This condition can temporarily damage the corneal tissues of the eye (clear transparent layer of the front portion of the eye). It may also affect the conjunctival tissues. Studies have shown that snow blindness is a type of photokeratitis that occurs when ultraviolet rays are reflected by snow and ice.

What Are the Causes of Photokeratitis?

Ultraviolet rays like UV-A and UV-B from the sun can cause short-term and long-term damage to the eyes. This can also affect vision and cause long-term damage to the eye's tissues. The UV-C radiation, however, is filtered and absorbed by the ozone layer and does not damage the eyes.

Direct staring or gazing at the sun during a solar eclipse could also result in photokeratitis and the long-term effects of photokeratitis. It could also cause retinal burns and temporary loss of vision. Here are some other causes of photokeratitis:

• Laser lights directly reflect into the eyes.

• Direct vision to sunlight and eye exposure to sunlight.

• Eye exposure to lamps used in tanning beds and booths.

• Direct eye exposure to arc welding equipment and photographic flood lamps.

• Direct eye exposure to lightning and electric sparks.

• Long-term or chronic eye exposure to mercury lamps and halogen desk lamps.

What Are the Symptoms of Photokeratitis?

A person may experience a series of eye symptoms on direct exposure to sunlight, ultraviolet rays, or any light source. The symptoms may last a few minutes to a few hours and are usually temporary.

Symptoms usually last from six hours to a couple of days. However, there may be long-lasting effects on chronic and repeated exposure. The following are the symptoms of photokeratitis:

• Eye redness and pain that may last for a few hours.

• Watery eyes.

• Tearing and burning sensation of the eyes.

• Blurred vision.

• Twitching of the eyelids.

• Frequent blinking of the eyes.

• Temporary loss of vision may be rare; however, it may occur.

• Extreme sensitivity to light until the symptoms subside.

• Seeing halos.

• Headaches and migraines.

• Color changes in the vision.

What Are the Long-Term Consequences of Photokeratitis?

• Chronic UV radiation can be damaging to the eyes. It can lead to cataracts, macular degeneration, and even blindness. The damage occurs because the UV rays damage the photoreceptor cells in the retina.

• In addition to these short-term effects, people with photokeratitis are more likely to develop a range of serious eye disorders, including cataracts and retinal detachment. Furthermore, even if one recovers from the initial symptoms, long-term corneal scarring can prevent clear vision for a lifetime.

• The long-term consequences of photokeratitis may also include permanent vision loss, scarring, and inflammation of the eye's tissues.

• Individuals with photokeratitis may also experience decreased sensitivity to light, making them more prone to developing conditions such as glaucoma. In addition, Pingueculae and pterygia (elevations on the surface of the eye due to chronic UV exposure) can also occur.

• Long-term exposure to blue and violet light emitted from LED lights, computers, laptop screens, and smartphones can also be a risk factor for photokeratitis and macular degeneration.

How Is Photokeratitis Diagnosed?

Ophthalmologists diagnose the eye condition after a thorough eye checkup and examine the changes in different light environments. In addition, routine eye examinations help the ophthalmologist determine the extent of eye damage.

The doctor may also conduct tests to diagnose superficial irregularities in the corneal tissues and eye surfaces. This process involves putting eye drops containing fluorescein into the eyes, which helps to understand the changes and eye damage clearly.

What Is the Treatment for Photokeratitis?

Usually, the condition or symptoms of photokeratitis go away on their own within a few hours to days (or even hours), as the condition is temporary. However, if symptoms persist for longer durations, it is important to seek medical attention or visit an ophthalmologist who may prescribe eye drops to mitigate the risk of infection.

Here are some necessary precautions to take if one experiences photokeratitis symptoms:

• Go indoors immediately.

• Consider staying in a less lit environment (dark room) in case of extreme light sensitivity.

• Remove the contact lenses till symptoms subside and one is comfortable wearing them again.

• Avoid rubbing eyes, as it will aggravate the condition and cause severe eye redness.

• The discomfort can be relieved by placing a cold washcloth over the closed eyes, using artificial tears, or taking pain-relieving medications as prescribed by an ophthalmologist.

How Can One Prevent Photokeratitis?

Here are some measures one can take to prevent photokeratitis -

• Wear proper eye protection, such as sunglasses or snow goggles. Sunglasses or goggles that block or absorb 99 % to 100 % of UV rays are recommended if one spends most of their time outdoors. Wrap-around sunglasses or those that protect the sides of the eyes (full coverage eyewear) are recommended to block all harmful UV rays. Glare from the snow, sand, or water can cause burns to the eyes, even if it is cloudy.

• One should wear a wide-brimmed hat during the day or extreme sunlight exposure.

• One should use eye protective equipment if exposed to UV radiation in their professional lives.

• One can opt for or consider wearing UV-absorbed contact lenses to protect their eyes.

• One must see an ophthalmologist or eye care specialist at least once a year for routine eye checkups to identify early symptoms of eye disorders and early signs of photokeratitis to prevent its long-term consequences.

Conclusion:

Photokeratitis is temporary when the eyes are directly exposed to ultraviolet rays, direct light, or sunlight. Symptoms include red eyes, burning, and irritation. One can opt for at-home remedies to relieve symptoms and prevent flare-ups or seek the right diagnosis and treatment from an ophthalmologist.

Preventive measures like wearing sunglasses or other protective equipment that blocks or absorbs UV rays when outside can prevent photokeratitis and its long-term effects on the eyes. Regular annual eye examinations can be beneficial in the early diagnosis and treatment of photokeratitis.