title: Imaging dermal blood flow through the intact rat skin with an optical clearing method.
abstract: Noninvasive detection of skin microcirculation is very significant for clinical diagnosis and therapy of peripheral vascular disease. In this study, an optical clearing method enables a laser speckle contrast imaging (LSCI) technique to image dermal blood flow through intact rat skin. The optical clearing effect of rat skin in vitro caused by a mixture of PEG-400 and Thiazone is evaluated by a commercially available spectrophotometer with an integrating sphere. A LSCI system is applied to image the dermal blood flow of in vivo rat skin after topical treatment of the agents. The results show that the reduced scattering coefficient (630 nm) is down to 60% of the initial value after 40 min of topical treatment of the mixture on skin in vitro. In vivo experimental results show that a 12-min treatment of the mixture on the epidermis can make the skin transparent and dermal vessels can be observed, while treatment with pure PEG-400 cannot. The process of skin optical clearing lasts, and the skin can be recovered by treatment of saline solution. Because optical clearing decreases the temporal contrast, dermal blood flow can be obtained by the laser speckle contrast imaging technique.
authors.affiliation: Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Wuhan 430074, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Zhu
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Zhongwei
authors.initials: Z
authors.lastname: Zhi
authors.forename: Xiang
authors.initials: X
authors.lastname: Wen
authors.forename: Qingming
authors.initials: Q
authors.lastname: Luo
mesh_terms: D000818:Animals; D003287:Contrast Media; D054459:Elasticity Imaging Techniques / Q000379:methods*; D007089:Image Enhancement / Q000379:methods*; D017078:Laser-Doppler Flowmetry / Q000379:methods*; D008297:Male; D008833:Microcirculation / Q000502:physiology*; D051381:Rats; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012867:Skin / Q000098:blood supply*; D012879:Skin Physiological Phenomena; D013829:Thiadiazines
chemical_list: D003287:Contrast Media; D013829:Thiadiazines; C012864:dazomet