What a novel dual-chamber vial brings to corneal preservation

Endothelial cell (EC) loss is the most frequent cause of corneal transplant failure, thus making endothelial preservation critical for good surgical outcomes.

The authors¹ of this presentation developed a novel dual-chamber corneal vial (DCV) comprised of two compartments that become isolated by the corneal graft and prevent epithelial and endothelial interaction.

Schematic of the DCV design showing the epithelial (A,B) and endothelial compartments (D,E) physically separated by the corneal graft (C). Panel F shows the vial closed and ready for storage. (Images courtesy of Joana Karanxha)

Current corneal vials (VC) differ from how the cornea exists naturally, where ECs are isolated and physically separated from the epithelium.

The authors hypothesize that the storage of corneal grafts in the DCV preserves the natural corneal environment, preventing corneal edema and better preserving corneal structure during cold storage, thus improving EC viability.

Methods

The Florida Lions Eye Bank recovered 9 human donor cornea pairs. For each pair, one cornea was stored in the VC and the other in the DCV.

The cornea pairs were preserved in Optisol-GS media and stored at 2–8°C for 2 weeks. Corneal thickness and EC density were evaluated at days 1, 7, and 14, and osmolarity was measured in preservation media after 2 weeks. Lactate dehydrogenase and annexin V levels were measured in the media and corneal tissue respectively, to assess for cytotoxicity and apoptosis.

Results

The authors’ findings showed increased corneal thickness in grafts stored in the VC compared to the DCV at all time points (days 1, 7, and 14).

Osmolarity was significantly increased in both the epithelial and endothelial compartments of the DCV compared to the VC, which the authors say suggests that the smaller volume in DCV compartments may lead to hyperosmolar conditions that preserve corneal stromal hydration.

There was no significant difference in EC density between chambers. Despite a small sample size, cytotoxicity was lower in the DCV endothelial media than the VC media in 6 of 8 samples, and annexin V concentrations were lower in the DCV endothelium than the VC endothelium in 5 of 6 samples.

Conclusions

The authors concluded that use of the dual-chamber corneal storage vial decreases corneal swelling, increases osmolarity, and potentially reduces endothelial apoptosis during corneal cold storage by physically separating the corneal epithelium and endothelium.

They believe the DCV has the potential to transform the way corneal grafts are preserved and will provide scientists with a platform to develop customized preservation solutions.

Joana Karanxha

jxk825@med.miami.edu

This article is based on Joana Karanxha’s presentation at the ARVO 2021 virtual annual meeting. Karanxha has no financial disclosures.

Reference

1. Karanxha J, Gomez-Bedoya A, Llanes KN, Persad PJ; Roper SD; Buras W; Fout E; Sabater AL. A novel dual-chamber vial for corneal preservation. IOVS. 2021:62;810.