Hyperspectral imaging for monitoring oxygen saturation levels during normothermic kidney perfusion

Abstract. The development of improved preservation techniques and the reliable assessment of donor grafts are main fields of research in transplantation medicine. Normothermic machine perfusion (NMP) is a promising alternative to static cold storage of organs, maintaining physiological conditions during preservation. In combination with NMP, we introduce hyperspectral imaging (HSI) as a novel approach for the monitoring of physiological kidney parameters. A line-scan HSI camera system was used to record images of porcine kidneys during NMP. Based on a dual-wavelength algorithm, the oxygen saturation levels were calculated from HSI recordings. Furthermore, we observed HSI images in the near-infrared (NIR) range in order to detect water characteristics of the kidney tissue. We found increasing levels of oxygenation during NMP and could discriminate between perfused and non-perfused areas. Cysts at the renal capsula were characterized by an absorption increase in the NIR band. Within this work, we showed that HSI is able to detect relevant chemical changes during NMP and allows the identification of pathologic variations.