Corneal Ulcer Figure 1

Figure 1: Corneal ulcer as a result of injury and infection in 3-month-old rat
Case history and photos


A three-month old male sustained a left eye injury while playing with his siblings.

Clinical Signs

Initially, the owner noticed heavy porphyrin discharge from the rat’s left eye. On closer inspection it was noticed that a scratch by his left eye went all the way into the eye. Within a week the rat’s left eye had became discolored and enlarged. The owner believed that the eye was too damaged for treatment and was planning to have it removed.


Examination of the left eye using a fluorescein eye stain showed the presence of a corneal ulcer as a result of severe infection due to injury.


The rat was treated with a course of a high-end dosage of oral Bayril, along with the application of Tobramycin ophthalmic solution 0.3% to the left eye every 3-4 hours.


After the first week the eye looked less discolored, and by two weeks of treatment the size of the eye had become normal. By three weeks of treatment the infection appeared to be cleared, however the eye was smaller than normal (microphthalmia). It is thought that the rat has lost the vision in the left eye.


There have been no other infectious issues with the eye.


corneal ulcer

In all three photos the left eye shows gross infection characterized by corneal edema and dense white infiltrate, which resulted in corneal ulceration due to initial corneal injury.

corneal ulcer

In these three photos the same left eye reflects remarkable healing, with resultant microphthalmia, following three weeks of treatment.

Case history and photos by: Joanne “Bella” Hodges


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