Antimicrobials and the corneal endothelium

Area of Science:

• Ophthalmology
• Corneal Science
• Toxicology

Background:

• The corneal endothelium is crucial for maintaining corneal clarity.
• Intraocular drug administration is common for treating eye infections and inflammation.
• Understanding the toxicity of intraocular agents on the corneal endothelium is vital for patient safety.

Purpose of the Study:

• To evaluate the toxic effects of various intraocular antibiotics and preservatives on the rabbit corneal endothelium.
• To compare the severity and duration of damage caused by different agents.
• To provide insights into the safety of intraocular drug injections.

Main Methods:

• Topical application and anterior chamber injection of antibiotics and preservatives in rabbits.
• Assessment of corneal endothelium using vital staining.
• Microscopic examination including light, scanning, and transmission electron microscopy.

Main Results:

• Benzalkonium chloride induced the most severe and likely irreversible endothelial damage.
• Methicillin caused persistent changes for up to 2 days.
• Gentamicin resulted in moderate, transient cellular edema.
• Dexamethasone and amphotericin B showed minimal effects.

Conclusions:

• Certain intraocular antibiotics and preservatives can cause significant damage to the corneal endothelium.
• The rabbit corneal endothelium, though robust, showed sensitivity to these agents.
• Caution is advised when considering intraocular injections of antibiotics due to potential endothelial toxicity.