Bunke Josefine, Merdasa Aboma, Sheikh Rafi, Albinsson John, Erlöv Tobias, Gesslein Bodil, Cinthio Magnus, Reistad Nina, Malmsjö Malin
Department of Clinical Sciences Lund, Ophthalmology, Lund University and Skåne University Hospital, Lund, Sweden.
Department of Physics, Lund University, Sweden.
Biomed Opt Express. 2021 Jun 15;12(7):4084-4096. doi: 10.1364/BOE.423876. eCollection 2021 Jul 1.
Clinical monitoring of blood oxygen saturation (sO) is traditionally performed using optical techniques, such as pulse oximetry and diffuse reflectance spectroscopy (DRS), which lack spatial resolution. Photoacoustic imaging (PAI) is a rapidly developing biomedical imaging technique that is superior to previous techniques in that it combines optical excitation and acoustic detection, providing a map of chromophore distribution in the tissue. Hitherto, PAI has primarily been used in preclinical studies, and only a few studies have been performed in patients. Its ability to measure sO with spatial resolution during local vasoconstriction after adrenaline injection has not yet been investigated. Using PAI and spectral unmixing we characterize the heterogeneous change in sO after injecting a local anesthetic containing adrenaline into the dermis on the forearm of seven healthy subjects. In comparison to results obtained using DRS, we highlight contrasting results obtained between the two methods arising due to the so-called 'window effect' caused by a reduced blood flow in the superficial vascular plexus. The results demonstrate the importance of spatially resolving sO and the ability of PAI to assess the tissue composition in different layers of the skin.
传统上，血氧饱和度（sO）的临床监测采用光学技术，如脉搏血氧测定法和漫反射光谱法（DRS），但这些技术缺乏空间分辨率。光声成像（PAI）是一种快速发展的生物医学成像技术，它优于以往的技术，因为它结合了光学激发和声学检测，能够提供组织中发色团分布的图谱。迄今为止，PAI主要用于临床前研究，仅有少数研究应用于患者。肾上腺素注射后局部血管收缩期间，PAI在空间分辨率下测量sO的能力尚未得到研究。我们利用PAI和光谱解混技术，对7名健康受试者前臂真皮内注射含肾上腺素的局部麻醉剂后sO的异质性变化进行了表征。与使用DRS获得的结果相比，我们强调了由于浅表血管丛血流减少导致的所谓“窗口效应”，两种方法之间产生了对比结果。结果证明了sO空间分辨率的重要性以及PAI评估皮肤不同层组织成分的能力。
