The cornea is the outermost clear, transparent integral layer located in the front of the iris and pupil. It is responsible for the involuntary eyelids reflex and helps to focus the light on the retina.  Any change in the cornea layer consistency causes altered vision. With a decrease in transparency of this layer, blurred vision can occur.

Common Symptoms of Corneal Diseases

You may need to seek professional help if there is:

  • Pain in the eye
  • Swelling
  • Distortion of visual image
  • Tearing
  • Redness
  • Blurred vision
  • Sensitivity to light
  • Corneal scarring
  • Decreased sharpness of vision

Types of Corneal Diseases and Related Symptoms

Sometimes, apart from minor injuries, corneal diseases occur for which you will need to seek help from an ophthalmologist or eye care professional. Common causes of corneal diseases and problems with the cornea include:

Refractive errors:

It includes nearsightedness, farsightedness, and astigmatism. In patients with refractive errors, the light that passes through the cornea does not bend correctly and focuses on the retina in the wrong place which causes blurred or imperfect vision.

Refractive errors


The cornea can recover on its own from minor injuries. The healthy cells slide over the scratched area very quickly and patch the injury before it affects vision or leads to infection. But in case of deep injury, the cornea needs longer time to heal. The deeper injury may also cause corneal scarring that can impair vision and needs a corneal laser ablation or corneal transplant.


Pollen related allergies are the most common type of allergies that affect the eyes, especially in the dry and warm season. The symptoms of a corneal disorder or disease due to allergies include itching, redness, burning sensation, tearing, stinging and watery discharge.



It is an inflammation of the cornea. Wearing contact lenses for a longer duration or minor injury may lead to non-infectious keratitis. Bacteria, fungi, viruses or parasites cause infectious keratitis. Such infections are related to trauma such as wearing contact lenses, any foreign body injury to eye, infected eye medication etc. When contact lenses are overused or are not cleaned properly, such infections occur. Antibacterial eye drops are prescribed to treat minor corneal infections. But for the severe problem, intensive treatment may be needed to eliminate the infection. Your ophthalmologist may also prescribe steroid eye drops under strict monitoring to minimize inflammation.

Dry eye:

In this condition, the eye is not able to keep its surface moist and lubricated and produces lower quality or quantity of tears. Dry eye causes scratchy feeling including other symptoms like burning in the eye, stinging, episodes of excess tearing followed by dryness, pain, and redness. Dry eyes can also lead to eye surface infections.

Ocular herpes

Ocular herpes:

Also known as ‘herpes of the eye’, it is a viral infection which tends to reoccur. The main cause of this eye condition is the Herpes Simplex Virus I (HSV I). It produces sores on the corneal surface and over a period of time, the inflammation spread deeper in the eye and cornea. Although there is no cure for ocular herpes, timely use of drugs help to control the condition.

Corneal degeneration and dystrophies:

These are a group of hereditary disease with corneal structural change or deposits due to genetic cause. There are several types of corneal degenerations and dystrophies. These diseases cause structural problems with the cornea. Keratoconus is a common type of genetic degeneration and causes thinning, protrusion, scarring of the cornea, blurred vision and blindness. As the cornea is thinned and altered in this condition, vision becomes blurry and is accompanied by other symptoms like:

  • Moderate to severe eye pain
  • Excessive tearing
  • Vision problems

  • A sensation that something is stuck in the eye

The common treatment in such cases is a corneal transplant. During the routine eye checkups and by knowing common symptoms of the corneal disease, such conditions are caught early. Your ophthalmologist can offer medical therapy that can help to avoid the transplant altogether.

Dr. Swapnali Sabhapandit