title: Properties of contact pressure induced by manually operated fiber-optic probes.
abstract: We assess the properties of contact pressure applied by manually operated fiber-optic probes as a function of the operator, probe contact area, and sample stiffness. First, the mechanical properties of human skin sites with different skin structures, thicknesses, and underlying tissues were studied by in vivo indentation tests. According to the obtained results, three different homogeneous silicone skin phantoms were created to encompass the observed range of mechanical properties. The silicon phantoms were subsequently used to characterize the properties of the contact pressure by 10 experienced probe operators employing fiber-optic probes with different contact areas. A custom measurement system was used to collect the time-lapse of diffuse reflectance and applied contact pressure. The measurements were characterized by a set of features describing the transient and steady-state properties of the contact pressure and diffuse reflectance in terms of rise time, optical coupling, average value, and variability. The average applied contact pressure and contact pressure variability were found to significantly depend on the probe operator, probe contact area, and surprisingly also on the sample stiffness. Based on the presented results, we propose a set of practical guidelines for operators of manual probes.
authors.affiliation: University of Ljubljana, Laboratory of Imaging Technologies, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia.
authors.forename: Maksimilijan
authors.initials: M
authors.lastname: Bregar
authors.affiliation: University of Ljubljana, Laboratory of Imaging Technologies, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia.
authors.forename: Blaž
authors.initials: B
authors.lastname: Cugmas
authors.affiliation: University of Ljubljana, Laboratory of Imaging Technologies, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia.
authors.forename: Peter
authors.initials: P
authors.lastname: Naglic
authors.affiliation: Ludwig-Maximilian University, Department of Dermatology and Allergology, Frauenlobstrasse 9-11, 80337 Munich, Germany.
authors.forename: Daniela
authors.initials: D
authors.lastname: Hartmann
authors.affiliation: University of Ljubljana, Laboratory of Imaging Technologies, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia.
authors.forename: Franjo
authors.initials: F
authors.lastname: Pernuš
authors.affiliation: University of Ljubljana, Laboratory of Imaging Technologies, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia.
authors.forename: Boštjan
authors.initials: B
authors.lastname: Likar
authors.affiliation: University of Ljubljana, Laboratory of Imaging Technologies, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia.
authors.forename: Miran
authors.initials: M
authors.lastname: Bürmen
mesh_terms: D001331:Automation; D004867:Equipment Design; D005336:Fiber Optic Technology / Q000295:instrumentation*; D006801:Humans; D008866:Microsurgery / Q000295:instrumentation*; D055100:Optical Fibers; D019047:Phantoms, Imaging; D011312:Pressure; D012825:Silicon / Q000737:chemistry; D012828:Silicones / Q000737:chemistry; D012867:Skin / Q000473:pathology*; D013053:Spectrophotometry; D013314:Stress, Mechanical; D059008:Time-Lapse Imaging
chemical_list: D012828:Silicones; D012825:Silicon