Graduate School of Bio-Applications & Systems Engineering, Tokyo University of Agriculture and Technology, Koganei 184-8588, Japan.
Department of Pathobiology, Faculty of Veterinary Medicine and Animal Science, Banghabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur 1706, Bangladesh.
Int J Mol Sci. 2021 Feb 3;22(4):1528. doi: 10.3390/ijms22041528.
Cyanosis is a pathological condition that is characterized by a bluish discoloration of the skin or mucous membranes. It may result from a number of medical conditions, including disorders of the respiratory system and central nervous system, cardiovascular diseases, peripheral vascular diseases, deep vein thrombosis, and regional ischemia. Cyanosis can also be elicited from methemoglobin. Therefore, a simple, rapid, and simultaneous monitoring of changes in oxygenated hemoglobin and deoxygenated hemoglobin is useful for protective strategies against organ ischemic injury. We previously developed a red-green-blue camera-based spectral imaging method for the measurements of melanin concentration, oxygenated hemoglobin concentration (), deoxygenated hemoglobin concentration (), total hemoglobin concentration () and tissue oxygen saturation () in skin tissues. We leveraged this approach in this study and extended it to the simultaneous quantifications of methemoglobin concentration (), , , and . The aim of the study was to confirm the feasibility of the method to monitor , , , , and . We performed in vivo experiments using rat dorsal skin during methemoglobinemia induced by the administration of sodium nitrite (NaNO) and changing the fraction of inspired oxygen (FiO), including normoxia, hypoxia, and anoxia. Spectral diffuse reflectance images were estimated from an RGB image by the Wiener estimation method. Multiple regression analysis based on Monte Carlo simulations of light transport was used to estimate , , , , and . rapidly increased with a half-maximum time of less than 30 min and reached maximal values nearly 60 min after the administration of NaNO, whereas dramatically dropped after the administration of NaNO, indicating the temporary production of methemoglobin and severe hypoxemia during methemoglobinemia. Time courses of and , while changing the FiO, coincided with well-known physiological responses to hyperoxia, normoxia, and hypoxia. The results indicated the potential of this method to evaluate changes in skin hemodynamics due to loss of tissue viability and vitality.
发绀是一种病理状态，其特征为皮肤或粘膜呈现蓝色变色。它可能由许多医学病症引起，包括呼吸系统和中枢神经系统紊乱、心血管疾病、周围血管疾病、深静脉血栓形成和局部缺血。高铁血红蛋白也可引起发绀。因此，对氧合血红蛋白和去氧血红蛋白的变化进行简单、快速和同步监测，对于防止器官缺血性损伤的保护策略很有用。我们之前开发了一种基于红绿蓝相机的光谱成像方法，用于测量皮肤组织中的黑色素浓度、氧合血红蛋白浓度（）、去氧血红蛋白浓度（）、总血红蛋白浓度（）和组织氧饱和度（）。我们在这项研究中利用了这种方法，并将其扩展到同时定量高铁血红蛋白浓度（）、、、和。本研究的目的是确认该方法监测、、、和的可行性。我们在大鼠背部皮肤进行了体内实验，通过给予亚硝酸钠（NaNO）诱导高铁血红蛋白血症，并改变吸入氧气分数（FiO），包括常氧、低氧和缺氧。通过 Wiener 估计方法从 RGB 图像估计光谱漫反射图像。基于光传输的蒙特卡罗模拟的多元回归分析用于估计、、、和。在给予 NaNO 后，迅速增加，半最大值时间小于 30 分钟，达到最大值接近 60 分钟，而在给予 NaNO 后，急剧下降，表明高铁血红蛋白血症期间临时产生高铁血红蛋白和严重低氧血症。在改变 FiO 时，和的时间过程与对高氧、常氧和低氧的已知生理反应相吻合。这些结果表明该方法有潜力评估由于组织失活和活力丧失而导致的皮肤血液动力学变化。
