A corneal ulcer is an eye condition that involves damage to parts of the corneal tissue. It is most commonly caused by bacterial infections. This article explains how a corneal ulcer develops and how it can be treated.
At a glance
- A corneal ulcer involves painful damage to the cornea.
- The condition is an emergency because it can result in a loss of sight.
- It is often caused by an infection with bacteria.
- Contact lenses can favor the development of a corneal ulcer.
- A corneal ulcer often heals after the treatment – but scars may remain on the cornea.
- Depending on their size and location, these may impair the eyesight.
Note: The information in this article cannot and should not replace a medical consultation and must not be used for self-diagnosis or treatment.
What is a corneal ulcer?
A corneal ulcer is a painful eye condition. The corneal tissue is damaged in the affected area.
An infection with bacteria, viruses or fungi can cause a corneal ulcer – as can mechanical injuries to the eye, such as scratches.
A corneal ulcer often heals after the causes have been treated – but scars may remain on the cornea.
What are the symptoms of a corneal ulcer?
Bad eye pain that can occur suddenly is one of the most common symptoms.
The eye is often reddened and streaming. The eyesight of many people with a corneal ulcer worsens and they become sensitive to light.
What causes a corneal ulcer?
There is a distinction between infectious and non-infectious causes.
Most corneal ulcers occur after a bacterial inflammation (infectious). The ulcers can also occur through an injury to the cornea, for example due to a scratch (non-infectious).
A so-called neurotrophic keratitis may also cause an ulcer. This rare disease, which involves the cornea not getting enough nutrients, favors corneal injuries. This, too, has many possible causes, including diabetes.
Another cause of corneal ulcers is toxic keratitis. This is an inflammation of the cornea that can occur as a result of medication applied externally.
What are the risk factors for a corneal ulcer?
A corneal ulcer can be favored by:
- contact lenses, particularly if they become dirty through being worn overnight, while swimming or showering
- a weakened immune system
- operations on the eye or eyelid
- an existing corneal inflammation due to illnesses such as diabetes mellitus, a stroke, or chemical burns
How is a corneal ulcer diagnosed?
A corneal ulcer can be diagnosed by examining the eye with a so-called split lamp. The device magnifies the eye as with a microscope, illuminating it using a narrow, slit-like beam of light. This enables the wound on the cornea to be detected clearly.
A swab can be taken to determine the cause of a corneal ulcer. A laboratory test then shows whether, for example, bacteria or fungi are the cause.
How is a corneal ulcer treated?
Doctors first treat the causes of the condition, i.e. the bacterial infection in most cases. Antibacterial drugs are then used, normally antibiotic eye drops.
Important: A corneal ulcer is an emergency, so a specialist should treat it as quickly as possible.
A corneal ulcer often heals after the causes have been treated – but scars may remain on the cornea. Depending on their size and location, these may make the eyesight worse.
If the condition worsens despite treatment, an operation may be necessary. An operation is also required if the cornea has been badly damaged by the ulcer. A cornea transplant may be needed if a lot of corneal tissue is destroyed.
- Alhassan MB, Rabiu M, Agbabiaka IO. Interventions for Mooren's ulcer. Cochrane Database Syst Rev. 2014 Jan 22;(1):CD006131. doi: 10.1002/14651858.CD006131.pub3. PMID: 24452998.
- DynaMed (Internet), Ipswich (MA). Corneal Ulcer. EBSCO Information Services. Record No. T900362. 2018 (1995). Aufgerufen am 02.02.2021.
In cooperation with the Institute for Quality and Efficiency in Health Care (Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen) (IQWiG).As at: