Development of a Swine Whole Eye Transplant Ex Vivo Perfusion Protocol

The first human Whole Eye Transplant (WET) has sparked new hope for patients who have lost vision due to major ophthalmic injury, but significant challenges remain to be addressed to achieve vision restoration. The eyeball, especially its neural components, undergoes nearly immediate degeneration unless adequately preserved. Oxygenated subnormothermic machine perfusion (SNMP) has emerged as a promising alternative to static cold storage (SCS), offering potential benefits for graft preservation and reconditioning.

WETs were procured from adult swine following a mean 164.7 ± 6.1 min of warm ischemia and perfused ex vivo using a Steen+ solution administered at room temperature for 18 h. Perfusion parameters, weight gain, and metabolic markers were recorded throughout the perfusion. Histological analysis and an atropine mydriasis test were performed to assess WET integrity and function.

Following an initial phase of metabolic clearance and weight loss, perfusion parameters stabilized, and final weight gain (t = 18 h) remained below 10%. Histological evaluation confirmed tissue preservation, and iris function was restored upon atropine administration.

This study represents the first application of SNMP to a whole eye composite transplant model, demonstrating promising outcomes in this large animal model and supporting SNMP as a potential alternative to SCS for WET.