The Interconnection Between Corneal Edema and Dry Eyes : Causes, Symptoms, and Treatment

Corneal edema is an increase in the thickness or swelling of the cornea that occurs due to the accumulation of the extracellular fluid in the epithelium and stoma that causes corneal transparency.

Dry eyes is a very common condition in which the tears cannot provide proper lubrication.

Both these conditions affect the eyes and vision. These can lead to light sensitivity. There is a close relation between corneal edema and dry eyes as the cornea needs a healthy tear film to maintain its clear and transparent state. Due to insufficient tear production, the cornea gets dehydrated leading to corneal edema. Also, corneal edema can exacerbate the symptoms of dry eyes as it further impairs the quality of the tear film.

The article clears the idea about corneal edema and dry eyes, their treatment, tips on preventing these eye conditions and the interconnection between dry eyes and corneal edema.

The cornea is the transparent outer surface of the eye that covers the pupil and the iris which are the colored part of the eye. The middle layer of the eye is known as a stoma. The innermost layer of the eye is known as the endothelium.

The function of the endothelium is to pump fluid out of the stoma. The inability of the endothelium to pump out fluid leads to the accumulation of fluid in the middle layer. This is known as corneal edema. This can occur due to several reasons, including:

• Eye injury or trauma
• Filtration problems in the cornea
• Inflammatory conditions like uveitis, keratitis
• Degenerative conditions such as Fuchs’ dystrophy
• Increased intraocular pressure in conditions like glaucoma
• Use of certain medications that can cause fluid buildup in the cornea
• Systemic medical conditions such as diabetes, which can affect the endothelium function

Corneal edema may lead to the following symptoms:

• Light sensitivity
• Discomfort with foreign particles
• Halos around the eye
• Pain in the eye

There are a few tests that can help in diagnosing corneal edema, which include:

• Visual acuity test: It measures the ability to see at different distances
• Slit-lamp examination: A special microscope is used to examine the front of the eye
• Corneal topography: It creates a map of the cornea surface and looks for any swelling or changes
• Tonometry: This test is done to measure the pressure inside the eyes
• Fluorescein angiography: This test involves injecting a dye into the bloodstream and then the pictures are taken using a special camera. It determines the fluid build-up in the cornea.

Dry eyes is a condition that is caused by a poor quantity of tears or poor tears production. It may be caused due to environmental factors, certain medications, allergies, and other medical conditions.

Dry eyes is a condition in which there is a decrease in tear production, an imbalance in tear composition, or excessive tear evaporation. Causes of dry eyes include:

• Aging
• Medications such as antihistamines, decongestants, and certain antidepressants
• Medical conditions like Sjogren’s syndrome, autoimmune disorders, and diabetes
• Environmental factors such as wind, dry air, and long hours in front of a computer screen
• Hormonal changes in women during menopause
• LASIK or other types of eye surgery
• Exposure to air conditioning or heating
• Contact lens wear

Dry eyes may lead to:

• Redness
• Feeling of something in the eye
• Fatigued eyes
• Blurred vision
• Scratchy, dry, painful sensation in the eyes
• Light sensitivity

Dry eyes can be diagnosed with the help:

• Eye examination
• Schirmer tear test: A test to measure the volume of tears
• Special dye tests: These are done to measure the quality of tears
• Osmolarity test: It tests the composition of the tears

The tear film is essential for maintaining the proper curvature and hydration of the cornea.⁽⁴⁾ Insufficient or imbalanced tear film may cause the cornea to get dehydrated and swell up. This may lead to corneal edema.

Also, insufficiency of tear film may cause the epithelial cells of the cornea to get damaged and further contribute to corneal swelling.⁽⁵⁾

Corneal edema can also lead to dry eyes. It alters the curvature and regularity of the cornea. This irregularity can scatter the light decreasing the clarity of the cornea. This reduces the quality of the tear film and makes it harder for the tears to spread evenly across the eye surface.⁽⁶⁾

Also, corneal swelling can compress the lacrimal glands that produce tears, leading to reduced tear production. This may aggravate the symptoms of dry eyes.

Corneal edema and dry eyes can create a cycle in which one condition can lead to the exacerbation of the other. It is therefore important to treat both conditions simultaneously.

Untreated corneal edema can worsen dry eyes and vice versa. This can lead to additional damage to the eyes.

Simultaneous treatment of both these conditions can help in addressing the root cause. Treating dry eyes can help in restoring the quality of the tear film, improve the hydration of the cornea, reduce swelling, and lead to an improvement in vision. On the other hand, treating corneal edema can help in restoring the proper shape and hydration of the cornea and reduce light scatter, and improve vision.

All of this can help improve vision and prevent further damage to the eyes.

There are various options for treating corneal edema and dry eyes.

Treatment of Corneal Edema

The treatment of corneal edema depends on the treatment of the underlying condition

If the cause is an inflammatory condition, the treatment goal is to reduce inflammation and decrease the pressure.

Hypertonic saline ointments or drops can be helpful in reducing corneal edema. The drops contain higher salt content than what is present in the body.⁽¹⁾

If someone develops corneal edema overnight, doctors also advise using a hair dryer to hasten the evaporation of tears.

If a person does not respond to medical treatment, Descemet’s stripping automated endothelial keratoplasty, a standard surgical treatment is recommended. This involves replacing the innermost layer of the cornea.

Treatment of dry eyes includes:⁽²⁾

• Over-the-counter medication including artificial eye drops
• Prescription medication may be given in more serious cases
• Lifestyle changes including drinking more water and avoiding smoky environments
• Tear duct plugs are used to avoid rapid evaporation of tears
• Surgery is recommended in case the lower lid is too loose causing the tears to drain out too fast.
• Other treatment options for dry eyes may include artificial tears, warm compresses, eyelid massage, and medications to improve tear production. In some cases, underlying medical conditions may need to be treated to resolve dry eye symptoms.

There are a few ways in which corneal edema or dry eyes can be prevented. These include:⁽³⁾

• Regular Eye Examination: Early detection and treatment of any eye condition can prevent them from worsening
• Keeping Informed: Knowing about the health condition that can cause eye problems and be helpful in preventing it by taking the required preventive measures
• Eating Eye-Healthy Foods: Eating foods rich in omega-3 fatty acids such as salmon, green, leafy vegetables, and spinach can be beneficial for eye health
• Quitting Smoking: Smoking increases the risk of certain eye conditions, therefore avoiding it can be beneficial for eye health
• Exercising Regularly: This can help in reducing the risk of health problems associated with causing eye problems such as diabetes
• Avoid Long Screen Time: If using a computer, every 20 minutes, breaks should be taken. This provides rest to the eyes
• Wearing Sunglasses: This protects the eyes from the ultraviolet rays of the sun

Corneal edema and dry eyes are related conditions and can exacerbate each other. Dry eyes cause corneal edema by reducing the quality of tear film and leading to dehydration and swelling of the cornea. On the other hand, corneal edema can cause dry eyes by altering the regularity of the cornea and affecting the quality of the tear film. Addressing the problem and treating the condition simultaneously can be helpful in breaking their vicious cycle.

Some lifestyle changes can also be helpful in preventing these eye conditions. Having a healthy lifestyle can be beneficial for the eye as well as other health problems.