Guo Hao, Stueck Ashley E, Doppenberg Jason B, Chae Yun Suk, Tikhomirov Alexey B, Zeng Haishan, Engelse Marten A, Gala-Lopez Boris L, Mahadevan-Jansen Anita, Alwayn Ian P J, Locke Andrea K, Hewitt Kevin C
Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Canada.
Department of Medical Physics, Nova Scotia Health Authority, Halifax, Canada.
J Biophotonics. 2024 Dec;17(12):e202400292. doi: 10.1002/jbio.202400292. Epub 2024 Oct 13.
Hepatic steatosis (HS), particularly macrovesicular steatosis (MaS), influences transplant outcomes. Accurate assessment of MaS is crucial for graft selection. While traditional assessment methods have limitations, non-invasive spectroscopic techniques like Raman and reflectance spectroscopy offer promise. This study aimed to evaluate the efficacy of a portable ambient light-compatible spectroscopic system in assessing global HS and MaS in human liver specimens.
A two-stage approach was employed on thawed snap-frozen human liver specimens under ambient room light: biochemical validation involving a comparison of fat content from Raman and reflectance intensities with triglyceride (TG) quantifications and histopathological validation, contrasting Raman-derived fat content with evaluations by an expert pathologist and a "Positive Pixel Count" algorithm. Raman and reflectance intensities were combined to discern significant (≥ 10%) discrepancies in global HS and MaS.
The initial set of 16 specimens showed a positive correlation between Raman and reflectance-derived fat content and TG quantifications. The Raman system effectively differentiated minimum-to-severe global and macrovesicular steatosis in the subsequent 66 specimens. A dual-variable prediction algorithm was developed, effectively classifying significant discrepancies (> 10%) between algorithm-estimated global HS and pathologist-estimated MaS.
Our study established the viability and reliability of a portable spectroscopic system for non-invasive HS and MaS assessment in human liver specimens. The compatibility with ambient light conditions and the ability to address limitations of previous methods marks a significant advancement in this field. By offering promising differentiation between global HS and MaS, our system introduces an innovative approach to real-time and quantitative donor HS assessments. The proposed method holds the promise of refining donor liver assessment during liver recovery and ultimately enhancing transplantation outcomes.
肝脂肪变性（HS），尤其是大泡性脂肪变性（MaS），会影响移植结果。准确评估MaS对于移植物选择至关重要。虽然传统评估方法存在局限性，但拉曼光谱和反射光谱等非侵入性光谱技术具有潜力。本研究旨在评估一种便携式环境光兼容光谱系统在评估人类肝脏标本中整体HS和MaS的有效性。
在室温环境光下，对解冻的速冻人类肝脏标本采用两阶段方法：生化验证，即将拉曼光谱和反射强度得出的脂肪含量与甘油三酯（TG）定量进行比较；组织病理学验证，将拉曼光谱得出的脂肪含量与专家病理学家的评估和“阳性像素计数”算法进行对比。结合拉曼光谱和反射强度，以识别整体HS和MaS中显著（≥10%）的差异。
最初的16个标本显示，拉曼光谱和反射光谱得出的脂肪含量与TG定量之间呈正相关。在随后的66个标本中，拉曼光谱系统有效地区分了轻度至重度的整体和大泡性脂肪变性。开发了一种双变量预测算法，有效地对算法估计的整体HS和病理学家估计的MaS之间的显著差异（>10%）进行了分类。
我们的研究证实了便携式光谱系统在非侵入性评估人类肝脏标本中HS和MaS的可行性和可靠性。与环境光条件的兼容性以及解决先前方法局限性的能力标志着该领域的重大进展。通过在整体HS和MaS之间实现有前景的区分，我们的系统引入了一种实时和定量评估供体HS的创新方法。所提出的方法有望在肝脏恢复过程中优化供体肝脏评估，并最终提高移植结果。
