title: Novel assessment tool based on laser speckle contrast imaging to diagnose severe ischemia in the lower limb for patients with peripheral arterial disease.
abstract: We propose a new assessment tool to diagnose severe ischemia of the lower limb in peripheral arterial disease, using laser speckle contrast imaging to evaluate heating-induced microcirculatory fluctuations in the proximal and distal sites of the dorsal foot.
  
  
  
  A cross-sectional study.
  
  
  
  We recorded the slope describing the behavior of perfusion values (decrease or plateau) following the initial, heating-induced increase in perfusion in 63 feet of patients with clinical signs of peripheral arterial disease.
  
  
  
  The plateau and decrease groups were defined as having perfusion slopes of <0.20 and ≥0.20 PU/min, respectively. Transcutaneous oxygen tension was significantly lower (P < 0.001) in the plateau than in the decrease group (8 vs. 45 mmHg), indicating more severe ischemia. The laser speckle contrast imaging thermal load test discriminated transcutaneous oxygen tension <30 mmHg with good sensitivity (78.7%) and specificity (96.2%), and an area under the curve of 0.908.
  
  
  
  Both transcutaneous oxygen tension and the laser speckle contrast imaging thermal load test are useful in diagnosing severe ischemia in the foot. Lasers Surg. Med. 49:645-651, 2017. © 2017. The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.
authors.affiliation: Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Sotaro
authors.initials: S
authors.lastname: Katsui
authors.affiliation: Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Inoue
authors.affiliation: Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Kimihiro
authors.initials: K
authors.lastname: Igari
authors.affiliation: Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Toyofuku
authors.affiliation: Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Kudo
authors.affiliation: Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Uetake
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D005528:Foot / Q000098:blood supply* / Q000000981:diagnostic imaging; D006801:Humans; D007511:Ischemia / Q000000981:diagnostic imaging* / Q000209:etiology; D054023:Lasers, Semiconductor; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D061848:Optical Imaging / Q000295:instrumentation / Q000379:methods*; D058729:Peripheral Arterial Disease / Q000150:complications*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
keywords: laser speckle contrast imaging; severe limb ischemia; thermal load test