SRS190 - Ex-situ multiparametric magnetic resonance imaging assessment of human pancreas grafts and the effects of oxygenated hypothermic machine perfusion

Abstract Background About half of surgically-retrieved pancreases are declined for transplantation. There is no validated objective pancreas graft assessment. Multiparametric magnetic resonance imaging (mp-MRI) is a non-invasive technique that can measure clinically-relevant parameters for pancreas grafts, such as steatosis and oedema. Oxygenated hypothermic machine perfusion (HMPO₂) is a novel method for pancreas preservation. This study evaluated mp-MRI feasibility for donor pancreases preserved in static cold storage (SCS) and its ability to evaluate the effects of HMPO₂-preservation. Methods Eight human pancreases, declined for transplantation, were enrolled. Two pancreases kept in SCS were used for protocol development and six underwent 6 h of HMPO₂ with mp-MRI assessment before and after HMPO₂ while in SCS. The mp-MRI protocol included: T₂* mapping to quantify residual blood; diffusion-weighted imaging to measure apparent diffusion coefficient (ADC) to assess oedema; and Dixon MRI to map fat fraction (FF). Results mp-MRI acquisition of ex-situ organs was feasible within 1 h while maintaining clinical-standard hypothermia. In the six HMPO₂-preserved pancreases ADC and wet-to-dry ratio trended up but did not show a significant increase in tissue oedema. HMPO2 improved microvascular flushing measured by increased T₂* indicating a reduction of residual blood. FF mapping revealed inter-organ variability, with good correlation between MRI and histological fat content. Conclusions Ex-situ mp-MRI of pancreases preserved in SCS is technically feasible and provides objective assessment of oedema, steatosis, and microvascular flushing and insights into the effects of HMPO₂. These findings support the potential role of mp-MRI as a non-invasive pancreas graft assessment tool.