Modification of the antibiotic system in M-K medium

Area of Science:

• Ophthalmology
• Corneal Preservation
• Antibiotic Efficacy

Background:

• Corneal storage media require antibiotics to prevent microbial contamination.
• The potential impact of antibiotics on corneal endothelial cell function is a critical consideration for organ preservation.

Purpose of the Study:

• To evaluate the effect of various antibiotics on corneal endothelial cell function and ultrastructure in preserved rabbit corneas.
• To determine the safety of commonly used antibiotics at supra-therapeutic concentrations in corneal storage media.

Main Methods:

• Rabbit corneas were stored in M-K medium supplemented with different antibiotics.
• Antibiotic concentrations were approximately ten times their minimum inhibitory concentrations.
• Corneal endothelial cell function and ultrastructure were assessed post-storage.
• Corneal thickness and endothelial layer integrity were monitored.

Main Results:

• Tobramycin, gentamicin, polymixin B, penicillin/streptomycin, cephaloridine, and cephalothin did not induce damage to corneal endothelia.
• Corneas stored with bacitracin exhibited no temperature reversals, unlike other groups.
• Bacitracin-treated corneas maintained stable thickness and intact endothelial layers.

Conclusions:

• Commonly used antibiotics, even at elevated concentrations, appear safe for corneal endothelial cells during storage.
• Bacitracin may offer a unique benefit in preventing temperature-related changes in corneal thickness without compromising endothelial integrity.