title: Tactile mapping system: a novel imaging technology for surface topography and elasticity of tissues or organs.
abstract: OBJECTIVE
  : We demonstrated that the tactile mapping system (TMS) has a high degree of spatial precision in the distribution mapping of surface elasticity of tissues or organs.
  
  
  METHODS
  : Samples used were a circumferential section of a small-caliber porcine artery (diameter: ∼3 mm) and an elasticity test pattern with a line and space configuration for the distribution mapping of elasticity, prepared by regional micropatterning of a 14-μm thick gelatin hydrogel coating on a polyurethane sheet. Surface topography and elasticity in normal saline were simultaneously investigated by TMS using a probe with a diameter of 5 or 12 μm, a spatial interval of 1 to 5 μm, and an indentation depth of 4 μm.
  
  
  RESULTS
  : In the test pattern, a spatial resolution in TMS of <5 μm was acquired under water with a minimal probe diameter and spatial interval of the probe movement. TMS was used for the distribution mapping of surface elasticity in a flat, circumferential section (thickness: ∼0.5 mm) of a porcine artery, and the concentric layers of the vascular wall, including the collagen-rich and elastin-rich layers, could be clearly differentiated in terms of surface elasticity at the spatial resolution of <2 μm.
  
  
  CONCLUSIONS
  : TMS is a simple and inexpensive technique for the distribution mapping of the surface elasticity in vascular tissues at the spatial resolution <2 μm. TMS has the ability to analyze a complex structure of the tissue samples under normal saline.
authors.affiliation: From the *Department of Bioengineering, Advanced Biomedical Engineering Center, National Cardiovascular Center Research Institute, Osaka, Japan; †Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, Hokkaido, Japan; ‡Shinkan Kogyo Co., Osaka, Japan; §College of Engineering, Nihon University, Fukushima, Japan; and ¶Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Tomonori
authors.initials: T
authors.lastname: Oie
authors.forename: Hisato
authors.initials: H
authors.lastname: Suzuki
authors.forename: Toru
authors.initials: T
authors.lastname: Fukuda
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Murayama
authors.forename: Sadao
authors.initials: S
authors.lastname: Omata
authors.forename: Keiichi
authors.initials: K
authors.lastname: Kanda
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Nakayama