Photokeratitis: Symptoms, Causes, Treatment

What are the symptoms of photokeratitis?

Photokeratitis is a painful eye condition caused by exposure to ultraviolet (UV) radiation, which can result from natural sources like sunlight or artificial sources such as welding torches, tanning beds, or snow reflection. It is essentially a sunburn of the cornea and conjunctiva. The symptoms typically appear a few hours after exposure and can vary in severity. Common symptoms of photokeratitis include:

1. Eye Pain and Discomfort:

• A sensation of pain, ranging from mild discomfort to severe pain.

2. Redness:

• Redness of the eyes (conjunctival injection) due to irritation and inflammation.

3. Tearing:

• Excessive tearing or watery eyes.

4. Gritty Sensation:

• A feeling of grittiness or foreign body sensation in the eyes.

5. Swelling:

• Swelling of the eyelids and around the eyes.

6. Blurred Vision:

• Temporary blurred vision or difficulty focusing.

7. Sensitivity to Light:

• Increased sensitivity to light (photophobia), which can make it uncomfortable to keep the eyes open in bright environments.

8. Headache:

• Headache may accompany other symptoms, especially if there is significant photophobia.

9. Halo Effect:

• Seeing halos around lights.

10. Temporary Vision Loss:

• In severe cases, temporary vision loss may occur, usually resolving within 24-48 hours.

The symptoms of photokeratitis typically resolve within 24 to 48 hours as the cornea heals, but it can be very uncomfortable during this period.

What are the causes of photokeratitis?

Photokeratitis is caused by exposure to ultraviolet (UV) radiation that damages the cornea and conjunctiva of the eye. This exposure can come from natural or artificial sources. Here are some common causes:

1. Sunlight:

• Direct Sun Exposure: Prolonged exposure to the sun without adequate eye protection, especially during peak UV radiation hours (10 a.m. to 4 p.m.), can cause photokeratitis.
• Reflection from Surfaces: UV rays reflected off surfaces like water, sand, or snow can increase exposure and risk. This is often referred to as “snow blindness” when it occurs in snowy environments.

2. Artificial Sources:

• Welding Torches: Exposure to the intense UV radiation emitted by welding torches can cause a type of photokeratitis known as “arc eye” or “welder’s flash.”
• Tanning Beds: UV lamps used in tanning beds can cause eye damage if protective goggles are not worn.
• Phototherapy Lamps: UV lamps used in certain medical treatments can also pose a risk if proper eye protection is not used.

3. Environmental Factors:

• High Altitudes: At higher altitudes, the atmosphere is thinner, leading to increased UV exposure. This is why mountaineers and skiers are at higher risk.
• Reflection from Water: Water bodies like oceans, lakes, and pools can reflect UV rays, increasing exposure.

4. Inadequate Eye Protection:

• Lack of Sunglasses: Not wearing sunglasses that block 100% of UVA and UVB rays can leave the eyes unprotected.
• Improper Use of Eye Protection: In some activities, even if eye protection is used, if it is not properly fitted or does not fully cover the eyes, it can lead to exposure.

Summary:

The primary cause of photokeratitis is exposure to UV radiation from natural sources like sunlight and reflections from surfaces such as water, sand, and snow, as well as artificial sources like welding torches, tanning beds, and phototherapy lamps. Inadequate eye protection and high altitudes can also increase the risk.

How is the diagnosis of photokeratitis made?

The diagnosis of photokeratitis is primarily clinical, based on a patient’s history of exposure to ultraviolet (UV) radiation and their symptoms. The following steps and techniques are typically used to diagnose photokeratitis:

1. Medical History:

• Exposure History: The healthcare provider will inquire about recent activities that could involve UV exposure, such as spending time outdoors without eye protection, skiing, visiting a tanning bed, or welding.
• Symptom Description: The patient will be asked to describe their symptoms, including onset, severity, and duration. Key symptoms include eye pain, redness, tearing, photophobia (light sensitivity), and a gritty sensation in the eyes.

2. Physical Examination:

• Eye Inspection: A visual examination of the eyes may reveal redness, swelling, and signs of irritation. The healthcare provider may use a slit lamp, a specialized microscope, to get a more detailed view of the eye’s surface.

3. Fluorescein Staining:

• A fluorescein dye may be applied to the surface of the eye. This dye temporarily stains the corneal surface, allowing the healthcare provider to see any areas of damage under a blue light. Corneal abrasions or damage, which appear as bright green areas, are indicative of photokeratitis.

4. Visual Acuity Test:

• A test may be performed to assess the patient’s vision and determine if it has been affected.

5. Ruling Out Other Conditions:

• The healthcare provider may need to differentiate photokeratitis from other eye conditions with similar symptoms, such as conjunctivitis (pink eye), dry eye, or foreign body presence. This may involve a more detailed examination or further questioning.

Summary:

Diagnosis of photokeratitis is based on a combination of the patient’s history of UV exposure, symptom presentation, and physical examination findings. Fluorescein staining is a key diagnostic tool for identifying damage to the cornea. The diagnosis is usually straightforward if the exposure history is clear and symptoms are consistent with photokeratitis.

What is the treatment for photokeratitis?

The treatment for photokeratitis focuses on alleviating symptoms and promoting healing. Since the condition usually resolves on its own within 24 to 48 hours, the primary goal is to provide comfort and prevent further damage. Here are the recommended treatments and care measures:

1. Remove the Source of UV Exposure:

• Avoid Further UV Exposure: Stay indoors or away from sources of UV radiation to prevent additional damage to the eyes.

2. Symptomatic Relief:

• Cold Compresses: Applying a cold compress to closed eyelids can help reduce pain and swelling.
• Lubricating Eye Drops: Use artificial tears or lubricating eye drops to soothe the eyes and provide moisture.
• Pain Relievers: Over-the-counter pain medications such as ibuprofen or acetaminophen can help manage pain and reduce inflammation.

3. Protective Measures:

• Sunglasses: Wear sunglasses that block 100% of UVA and UVB rays to protect the eyes from further UV exposure and reduce light sensitivity.
• Avoid Rubbing Eyes: Refrain from rubbing the eyes, as this can exacerbate irritation and damage.

4. Medical Treatment:

• Antibiotic Ointment or Drops: In some cases, a healthcare provider may prescribe antibiotic eye drops or ointment to prevent secondary infections, especially if there are corneal abrasions.
• Cycloplegic Drops: These may be prescribed to relieve pain by temporarily paralyzing the ciliary muscles, which can reduce spasms and pain.

5. Follow-Up Care:

• Monitoring Symptoms: Keep track of symptoms and seek medical attention if they worsen or do not improve within 48 hours.
• Eye Examination: A follow-up examination with an eye care professional may be necessary to ensure proper healing and rule out any complications.

Prevention:

• Wear Protective Eyewear: Use sunglasses with UV protection, safety goggles, or welding helmets as appropriate to prevent future incidents of photokeratitis.
• Be Mindful of Reflective Surfaces: Take extra precautions when in environments with high UV reflection, such as snowy or sandy areas.

Summary:

Treatment for photokeratitis includes symptomatic relief with cold compresses, lubricating eye drops, and pain relievers, as well as protective measures like wearing sunglasses and avoiding further UV exposure. In some cases, antibiotic eye drops or cycloplegic drops may be prescribed. Symptoms typically resolve within 24 to 48 hours, but follow-up care may be needed if symptoms persist or worsen.