Occasionally, a relationship may exist between corneal edema and dry eye. If dry eye is severe, it might lead to corneal edema.

Corneal edema is the accumulation of fluid in the transparent part of the eye that covers the iris and pupil.

Both dry eye and corneal edema can cause light sensitivity, but each has its own symptoms, such as redness in dry eye and halos around lights in corneal edema.

The treatment of dry eyes differs from the treatment of corneal edema. Treatments for dry eye may entail using artificial tears or avoiding smoky environments. Treatment for corneal edema can include using hypertonic saline drops.

This article discusses corneal edema and dry eye, including the symptoms and treatment of each. It also offers tips on how to prevent eye conditions.

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Medical News Today reached out to Howard R. Krauss, MD. He is the surgical neuro-ophthalmologist and director of Pacific Neuroscience Institute’s Eye, Ear & Skull Base Center at Providence Saint John’s Health Center in Santa Monica, CA.

“There are many potential causes of corneal edema,” said Krauss. “While mild dry eye is an unlikely cause, a more severe dry eye state may lead to corneal surface breakdown with consequent corneal edema.

“Additionally, people may have adverse reactions to over-the-counter eye drops, prescription eye drops, or both when treating their underlying dry eye condition. Such adverse reactions may stem from an allergic or toxic response to eye drop ingredients. The irritation that ensues can cause the breakdown of the cornea, which may lead to corneal edema,” Krauss said.

Read more about dry eyes here.

The cornea is the transparent outer surface of the eye that covers the pupil and iris, the colored part of the eye.

“It is a 1/2-millimeter thick structure with five layers,” said Krauss. “The middle layer is the stroma. In corneal edema, there is an accumulation of fluid in the stroma, which may lead to clouded vision.

“It is the function of the endothelium, the innermost layer of the cornea, to actively pump fluid out of the stroma, but the endothelium may be overcome by various factors,” Krauss said.

These factors can include:

  • loss of endothelial cells
  • dysfunction of endothelial cells
  • high pressure within the eye
  • inflammation

“Additionally, the breakdown of the epithelium, or outer protective layer, may result in a chronic irritation that overcomes the pumping job of the endothelium. This can lead to fluid accumulation within the stroma,” Krauss said.

Corneal edema is a common sign of short- or long-term conditions affecting the cornea, according to a 2013 research paper.

Symptoms of corneal edema include:

  • light sensitivity
  • halos around lights
  • discomfort to foreign particles
  • pain in the eye

Dry eye is a common condition. Its symptoms include:

  • light sensitivity
  • redness
  • blurred vision
  • a scratchy feeling or sensation that something is in the eye
  • burning or stinging

Causes of dry eye include:

  • the glands not producing enough tears to keep the eye moistened
  • tears not working well enough to maintain eye moisture
  • tears evaporating too quickly

Other causes involve:

  • Medications: Dry eye is a side effect of medications for certain conditions, such as:
    • high blood pressure
    • depression
    • colds and allergies
  • Laser eye surgery: Some types of laser surgery may result in the production of fewer tears for a time.
  • Long screen time: Looking at a screen for a long time may result in less blinking, which can dry the eyes.
  • Health conditions: Some conditions may cause dry eye, including:
    • thyroid disorders
    • diabetes
    • autoimmune disorders, such as Sjogren’s disease or lupus
  • Smoky, windy, or dry environments: Spending time in these places can lead to tears drying up more quickly.

Treatment depends on the underlying cause.

For example, in inflammatory conditions, the treatment goal is to reduce inflammation. Or for glaucoma, the treatment goal is to decrease the pressure.

Additionally, hypertonic saline ointment or drops can temporarily reduce corneal edema. Hypertonic saline drops contain a higher salt content than what is present in the body. For people whose edema builds up overnight, some doctors may advise using a hair dryer to hasten the evaporation of tears.

In cases that do not respond to medical treatment, the standard surgical treatment is Descemet’s stripping automated endothelial keratoplasty (DSEK). It replaces the innermost layer of the cornea.

Treatment for dry eyes includes the following:

  • Over-the-counter medications: Artificial tears may help mild cases. Moisturizing ointments and gels may also make dry eyes feel more comfortable.
  • Prescription medications: Doctors may prescribe lifitegrast (Xiidra) or cyclosporine (Restasis) for more serious cases. These medications help the eyes produce more tears.
  • Lifestyle changes: These may entail measures such as drinking more water or avoiding smoky environments whenever possible. They may also involve changing a medication that has the side effect of drying the eyes.
  • Tear duct plugs: If tears evaporate too rapidly from the eye, special devices called punctal plugs can help maintain the tears in the eye.
  • Surgery: If the lower eyelids are too loose, tears can drain out too fast. When this happens, surgical repair of the eyelids may help, but doctors do not often use this treatment.

Below are some ways of preventing eye conditions:

  • Get a dilated eye exam: Early detection and treatment of some eye conditions can help prevent them from worsening.
  • Talk with a doctor about health conditions: Some health problems increase the likelihood of eye conditions. A person can ask their doctor whether they are at risk.
  • Eat eye-healthy foods: These include foods rich in omega-3 fatty acids, such as salmon. Green, leafy vegetables, such as spinach, are also beneficial for eye health.
  • Quit smoking: Smoking raises the risk of some eye diseases and damages the optic nerve.
  • Exercise regularly: Exercise reduces the risk of health problems that may cause eye conditions, such as diabetes.
  • Wear protective eyewear: Wear safety glasses when playing sports, making home repairs, or doing construction work.
  • Avoid long periods of screen time: Every 20 minutes, people should take a break from their computer screen to look at something in the distance for 20 seconds.
  • Wear sunglasses: Sunglasses help protect the eyes from the sun’s ultraviolet radiation.

Visit our hub to learn more about eye health here.

Corneal edema and dry eye are two separate eye conditions, but sometimes there is a connection between them. Dry eye may cause corneal edema if it is severe or if medications used to treat dry eye produce irritation.

Symptoms common to both conditions may include light sensitivity, eye discomfort, and decreased vision. Other than these, the symptoms often differ.

The causes and treatment of the two conditions are also dissimilar.

Some lifestyle strategies can help prevent eye conditions. Examples include quitting smoking, if applicable, and eating a nutritious diet.