title: Low-cost compact diffuse speckle contrast flowmeter using small laser diode and bare charge-coupled-device.
abstract: We report a low-cost compact diffuse speckle contrast flowmeter (DSCF) consisting of a small laser diode and a bare charge-coupled-device (CCD) chip, which can be used for contact measurements of blood flow variations in relatively deep tissues (up to  ∼ 8  mm). Measurements of large flow variations by the contact DSCF probe are compared to a noncontact CCD-based diffuse speckle contrast spectroscopy and a standard contact diffuse correlation spectroscopy in tissue phantoms and a human forearm. Bland–Altman analysis shows no significant bias with good limits of agreement among these measurements: 96.5%±2.2% (94.4% to 100.0%) in phantom experiments and 92.8% in the forearm test. The relatively lower limit of agreement observed in the in vivo measurements (92.8%) is likely due to heterogeneous reactive responses of blood flow in different regions/volumes of the forearm tissues measured by different probes. The low-cost compact DSCF device holds great potential to be broadly used for continuous and longitudinal monitoring of blood flow alterations in ischemic/hypoxic tissues, which are usually associated with various vascular diseases.
authors.affiliation: University of Kentucky, Department of Biomedical Engineering, 143 Graham Avenue, Lexington, Kentucky 40506, United States.
authors.forename: Chong
authors.initials: C
authors.lastname: Huang
authors.affiliation: University of Kentucky, Department of Biomedical Engineering, 143 Graham Avenue, Lexington, Kentucky 40506, United StatesbGwangju Institute of Science and Technology, Department of Biomedical Science and Engineering, 123 Cheomdan Gwagiro, Bukgu, Gwangju 6.
authors.forename: Myeongsu
authors.initials: M
authors.lastname: Seong
authors.affiliation: University of Kentucky, Department of Electrical and Computer Engineering, 512 Administration Drive, Lexington, Kentucky 40506, United States.
authors.forename: Joshua Paul
authors.initials: JP
authors.lastname: Morgan
authors.affiliation: University of Kentucky, Department of Biomedical Engineering, 143 Graham Avenue, Lexington, Kentucky 40506, United States.
authors.forename: Siavash
authors.initials: S
authors.lastname: Mazdeyasna
authors.affiliation: Gwangju Institute of Science and Technology, Department of Biomedical Science and Engineering, 123 Cheomdan Gwagiro, Bukgu, Gwangju 61005, Republic of Korea.
authors.forename: Jae Gwan
authors.initials: JG
authors.lastname: Kim
authors.affiliation: University of Kentucky, Department of Electrical and Computer Engineering, 512 Administration Drive, Lexington, Kentucky 40506, United States.
authors.forename: Jeffrey Todd
authors.initials: JT
authors.lastname: Hastings
authors.affiliation: University of Kentucky, Department of Biomedical Engineering, 143 Graham Avenue, Lexington, Kentucky 40506, United States.
authors.forename: Guoqiang
authors.initials: G
authors.lastname: Yu
mesh_terms: D005542:Forearm; D006439:Hemodynamics; D006801:Humans; D017078:Laser-Doppler Flowmetry / Q000191:economics / Q000295:instrumentation*; D019047:Phantoms, Imaging; D012039:Regional Blood Flow; D013057:Spectrum Analysis