Journal of Imaging (Aug 2024)

Ex Vivo Simultaneous H<sub>2</sub><sup>15</sup>O Positron Emission Tomography and Magnetic Resonance Imaging of Porcine Kidneys—A Feasibility Study

  • Maibritt Meldgaard Arildsen,
  • Christian Østergaard Mariager,
  • Christoffer Vase Overgaard,
  • Thomas Vorre,
  • Martin Bøjesen,
  • Niels Moeslund,
  • Aage Kristian Olsen Alstrup,
  • Lars Poulsen Tolbod,
  • Mikkel Holm Vendelbo,
  • Steffen Ringgaard,
  • Michael Pedersen,
  • Niels Henrik Buus

DOI
https://doi.org/10.3390/jimaging10090209
Journal volume & issue
Vol. 10, no. 9
p. 209

Abstract

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The aim was to establish combined H215O PET/MRI during ex vivo normothermic machine perfusion (NMP) of isolated porcine kidneys. We examined whether changes in renal arterial blood flow (RABF) are accompanied by changes of a similar magnitude in renal blood perfusion (RBP) as well as the relation between RBP and renal parenchymal oxygenation (RPO). Methods: Pig kidneys (n = 7) were connected to a NMP circuit. PET/MRI was performed at two different pump flow levels: a blood-oxygenation-level-dependent (BOLD) MRI sequence performed simultaneously with a H215O PET sequence for determination of RBP. Results: RBP was measured using H215O PET in all kidneys (flow 1: 0.42–0.76 mL/min/g, flow 2: 0.7–1.6 mL/min/g). We found a linear correlation between changes in delivered blood flow from the perfusion pump and changes in the measured RBP using PET imaging (r2 = 0.87). Conclusion: Our study demonstrated the feasibility of combined H215O PET/MRI during NMP of isolated porcine kidneys with tissue oxygenation being stable over time. The introduction of H215O PET/MRI in nephrological research could be highly relevant for future pre-transplant kidney evaluation and as a tool for studying renal physiology in healthy and diseased kidneys.

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