Corneal ulcers: Causes, symptoms, diagnosis, and treatment

29 April 2021

Author: Kate Green

corneal ulcer

What is a corneal ulcer?


A corneal ulcer is an open sore on the cornea, the transparent layer which forms the front of your eye. The cornea covers your iris (the coloured part of your eye) and your pupil (the black centre of your eye), so a corneal ulcer can have devastating impacts on your vision if left untreated. You can’t always see a corneal ulcer, but sometimes there will be a white spot on your cornea which is visible when you look closely in the mirror. Corneal ulcers can occur for a number of reasons but usually result from an eye infection.


What are the symptoms of a corneal ulcer?


If you have a corneal ulcer, you will certainly notice it. The symptoms can be very distressing and uncomfortable, including:

  • Eye redness
  • Pain
  • Swollen eyelids
  • Foreign body, gritty sensation
  • Light sensitivity
  • Excessive eye discharge
  • Watery eyes


As previously mentioned, on top of these symptoms, you may also have a white spot visible on the surface of your eye. If you experience any of the above symptoms, you should visit your optician to have your eye checked and to receive the necessary treatment. If you experience any further severe pain or changes to your vision, you should again seek help urgently.


What causes a corneal ulcer?


Corneal ulcers usually occur as a result of an eye infection. These eye infections can be bacterial, viral, fungal or parasitic, so it’s important that you visit a specialist who can help you identify the cause of your corneal ulcer and administer the appropriate treatment. Knowing what has caused your corneal ulcer can also help you to prevent it from occurring again in the future.


People who wear contact lenses increase their risk of developing a corneal ulcer ten-fold, particularly if they wear overnight soft contact lenses. This is because bacteria on the contact lens can become trapped between the surface of your eye and the lens itself, allowing a bacterial infection to develop. Further to this, if you wear your lenses for extended periods of time, your cornea doesn’t receive any oxygen which in turn increases the chances of an infection developing. Ill-fitting lenses can also scratch your cornea which, again, increases the risk of infection.


You are more likely to develop a corneal ulcer if you:

  • Regularly wear contact lenses
  • Sleep with contact lenses in overnight
  • Suffer with dry eyes
  • Use steroid eye drops
  • Have Bell’s palsy (as this can cause the cornea to dry out)
  • Experience in-growing eyelashes
  • Fail to wash your hands before handling contact lenses


Each of these factors can increase your risk factor for corneal ulcers. Seeking treatment for the issues above, where possible, could help prevent a corneal ulcer from occurring and threatening your sight in the future.


How can you treat a corneal ulcer?


Eye drops are the most commonly-used method to treat and cure corneal ulcers. Depending on the type of infection causing the corneal ulcer, you will be prescribed antibiotic, antifungal or antiviral eye drops to help your eye heal.  It can often take 2-3 weeks before the ulcer is healed and most doctors will ask you to check in with them every couple of days to ensure that the process of recovery is going smoothly.


As well as eye drops, your doctor might also recommend that you take oral pain medication to help manage any discomfort. The pain caused by corneal ulcers can be quite strong so painkillers and cool compresses to reduce to swelling can go a long way to easing the discomfort.


If there has been permanent damage to your cornea from the ulcer, it is possible that you will need a corneal transplant. This especially applies to people who have experienced the ulcer in the middle of their cornea, as this can obstruct vision significantly. In a corneal transplant procedure, the surgeon will replace your damaged cornea with a healthy cornea from a donor. This process restores your vision after the trauma caused by a corneal ulcer.


Moving forwards, it is important that you observe good hand and eye hygiene, especially when it comes to contact lenses, in order to prevent the occurrence of a corneal ulcer as much as you can. Taking care to ensure that your eyes are well hydrated and lubricated can also help with preventing the further development of ulcers, and therefore will help preserve good vision.

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