Atherosclerosis is a lipid-driven and an inflammatory disease of the artery walls. The composition of atherosclerotic plaque stratifies the risk of a specific plaque to cause a cardiovascular event. In an optical resolution photoacoustic microscopy setup, of 45 μm resolution, we extracted plaque lipid photoacoustic (PA) spectral signatures of human endarterectomy samples in the range of 1150–1240 nm, using matrix assisted laser desorption ionization mass spectrometry imaging as a reference. We found plaque PA signals to correlate best with sphingomyelins and cholesteryl esters. PA signal spectral variations within the plaque area were compared to reference molecular patterns and absorption spectra of lipid laboratory standards. Variability in the lipid spectroscopic features extracted by principal component analysis of all samples revealed three distinct components with peaks at: 1164, 1188, 1196 and 1210 nm. This result will guide the development of PA-based atherosclerosis disease staging capitalizing on lipidomics of atherosclerotic tissue.

动脉粥样硬化是脂质驱动的动脉壁炎性疾病。动脉粥样硬化斑块的成分可将特定斑块引起心血管事件的风险分层。在分辨率为45μm的光学分辨率光声显微镜设置中，我们以基质辅助激光解吸电离质谱成像为参考，提取了1150–1240 nm范围内的人类动脉内膜切除术样本的斑块脂质光声（PA）光谱特征。我们发现斑块PA信号与鞘磷脂和胆固醇酯最相关。将噬斑区域内的PA信号光谱变化与脂质实验室标准品的参考分子图和吸收光谱进行了比较。通过对所有样品进行主成分分析而提取的脂质光谱特征的变异性揭示了三个不同的成分，其峰值分别在1164、1188、1196和1210 nm。该结果将指导利用动脉粥样硬化组织的脂质组学开发基于PA的动脉粥样硬化疾病分期。