---
title: What is a corneal ulcer?
description: "A corneal ulcer is an open sore on the cornea, usually due to infection following an epithelial defect. It is a vision‑threatening emergency requiring prompt assessment and treatment. ## Causes and Symptoms Bacterial, fungal, viral, or amoebic infections can all…"
url: "https://bluefinvision.com/knowledge-base/topics/conditions-diseases/what-is-a-corneal-ulcer/"
updated: "2025-12-15"
category: "Conditions & Diseases"
---

# What is a corneal ulcer?

A corneal ulcer is an open sore on the cornea, usually due to infection following an epithelial defect. It is a vision‑threatening emergency requiring prompt assessment and treatment.

## Causes and Symptoms

Bacterial, fungal, viral, or amoebic infections can all cause ulcers, particularly in contact lens wearers or eyes with trauma or severe dry eye.

- Symptoms include severe pain, redness, discharge, light sensitivity, and reduced vision.
- Examination reveals a focal epithelial defect with underlying stromal infiltrate and often surrounding oedema.
- Intraocular inflammation and hypopyon may be present in more advanced cases.
- Untreated ulcers can perforate and lead to endophthalmitis or scarring.

## Treatment

Management involves intensive topical antimicrobial therapy tailored to the suspected organism and culture results.

- Frequent follow‑up is needed to monitor healing and adjust treatment.
- Cycloplegic drops relieve pain and help prevent synechiae.
- Adjunctive measures such as lubricants, bandage contact lenses, or amniotic membrane grafts support epithelial healing.
- Residual scarring may require optical correction or keratoplasty.