Affecting factors on optical clearing of bio-tissues: Ⅰ Tissue anatomical structures Ⅱ Permeation property of hyperosmotic agents

摘要

With an effort to understand the impacting factors on optical clearing of tissues and to look for effective clearing, two types of tissues i. e. muscle tissue (porcine skeletal muscle) and epithelial tissue (porcine stomach mucosa) treated with glycerol are investigated by the use of optical coherence tomography (OCT) and near infrared spectroscopy. Stomach mucosa applied with mixed solutions of glycerol and dimethyl sulfoxide (DMSO) is furthermore studied. The improved contrast among different layers in the both tissues is visualised with the OCT assessment. The overall increase in light transmittance in the muscle and the mucosal tissue at 30 min after the application of 80% glycerol are approximate 21% and 16%, decrease in diffuse reflectance are 33% and 21%, respectively. The different anatomical structures of muscle and mucosal tissue probably account for the difference in clearing effect between the two tissues. For stomach mocusa, 50% glycerol with 30% DMSO shows significantly stronger clearing effect than 80% glycerol. High permeability and enhancer activity of DMSO are thought to aid in the synergistic clearing effect. It is concluded that the optical clearing accomplished by the hyperosmotic agents is strongly dependent on anatomical structure of tissue and permeation property of clearing agents, which must be taken into account for effective clearing.