The Evolution of Ocular Preservation

Whole eye transplant perfusion represents a major leap in ophthalmic surgery and restorative medicine. While the world's first human eye transplant recently demonstrated structural success, achieving vision restoration remains the ultimate goal for clinicians. Therefore, researchers are actively developing innovative ways to keep donor eyes healthy before surgery. Currently, traditional static cold storage often leads to rapid tissue decay and metabolic failure. Consequently, oxygenated subnormothermic machine perfusion (SNMP) has emerged as a superior alternative for preserving delicate ocular and neural structures.

Establishing the SNMP Protocol

A recent study utilized adult swine models to test a sophisticated 18-hour perfusion protocol. Specifically, the team procured grafts following a period of warm ischemia and used a specialized Steen+ solution at room temperature. Unlike cold storage, this method allows the tissue to remain metabolically active during the preservation phase. Additionally, the researchers monitored perfusion parameters and weight gain throughout the process to ensure graft stability. The results were highly encouraging, as the eyes showed metabolic clearance and final weight gain remained below 10%.

Advancing Clinical Outcomes with Whole Eye Transplant Perfusion

Histological analysis confirmed that the SNMP protocol effectively maintained tissue integrity across the composite transplant model. Furthermore, the iris regained functional capacity, as demonstrated by a successful atropine mydriasis test. These findings suggest that SNMP can successfully bridge the gap between procurement and transplantation. Overall, this large animal model supports the shift away from cold storage toward more dynamic preservation techniques. This progress brings the medical community closer to the reality of functional human eye transplants.

Frequently Asked Questions

What is the primary benefit of SNMP over static cold storage?

SNMP allows the donor eye to remain metabolically active and receive oxygenated nutrients. This process reduces the rapid degeneration seen in cold storage, especially in sensitive neural components like the retina.

How was the success of the eye function measured in this study?

Researchers used histological evaluation to confirm tissue preservation and performed an atropine mydriasis test. The successful dilation of the iris indicated that the eye's functional integrity was restored after 18 hours of perfusion.

Does this study mean human vision restoration is now possible?

While this study is a critical step in preserving the eye for transplant, vision restoration requires the regeneration of the optic nerve to the brain. This protocol focuses on keeping the eye viable enough to make that future step possible.

Disclaimer: This content is for informational and educational purposes only and does not constitute medical advice or a professional recommendation. The field of whole eye transplantation is experimental. Refer to the latest local and national guidelines for clinical practice.

References

Oubari H et al. Development of a Swine Whole Eye Transplant Ex\u00a0Vivo Perfusion Protocol. Artif Organs. 2026 Mar 19. doi: 10.1111/aor.70118. PMID: 41856924.

Dedania VS et al. Clinical Outcomes of the First Human Whole-Eye and Partial-Face Transplant. JAMA. 2024;332(14):1180\u20131189. doi:10.1001/jama.2024.12601.

Tse DT et al. Paving the way for human eye transplants. University of Miami News. July 24, 2025.