Due to the shortage of kidneys donated for transplantation, surgeons are forced to use the organs with an elevated risk of poor function or even failure. Although the existing methods for pre-transplant quality evaluation have been validated over decades in population cohort studies across the world, new methods are needed as long as delayed graft function or failure in a kidney transplant occurs. In this study, we explored the potential of utilizing photoacoustic (PA) imaging during normothermic machine perfusion (NMP) as a means of evaluating kidney quality. We closely monitored twenty-two porcine kidneys using 3D PA imaging during a two-hour NMP session. Based on biochemical analyses of perfusate and produced urine, the kidneys were categorized into ‘non-functional’ and ‘functional’ groups. Our primary focus was to quantify oxygenation () within the kidney cortical layer of depths 2mm, 4mm, and 6mm using two-wavelength PA imaging. Next, receiver operating characteristic (ROC) analysis was performed to determine the optimal cortical layer depth and time point for quantification of to discriminate between functional and non-functional organs. Finally, for each depth, we assessed the correlation between and creatinine clearance (), oxygen consumption (), and renal blood flow (RBF).

中文翻译：

---

常温机器灌注期间使用光声成像评估移植前肾脏质量

由于用于移植的肾脏短缺，外科医生被迫使用功能不良甚至衰竭风险较高的器官。尽管现有的移植前质量评估方法已在世界各地的人群队列研究中得到了数十年的验证，但只要发生移植功能延迟或肾移植失败，就需要新的方法。在这项研究中，我们探索了在常温机器灌注（NMP）过程中利用光声（PA）成像作为评估肾脏质量的手段的潜力。我们在两个小时的 NMP 会议期间使用 3D PA 成像密切监测 22 个猪肾脏。根据灌注液和产生的尿液的生化分析，肾脏被分为“无功能”和“有功能”组。我们的主要重点是使用双波长 PA 成像来量化深度 2mm、4mm 和 6mm 的肾皮质层内的氧合 ()。接下来，进行接受者操作特征（ROC）分析，以确定最佳皮质层深度和时间点，以量化区分功能性器官和非功能性器官。最后，对于每个深度，我们评估了肌酐清除率 ()、耗氧量 () 和肾血流量 (RBF) 之间的相关性。