title: Indocyanine green videoangiography-assisted prediction of flap necrosis in the rat epigastric flap using the flow®800 tool.
abstract: BACKGROUND
  The decision to re-operate on a potentially ischemic free flap remains challenging. Indocyanine green videoangiography (ICG) with the FLOW®800 tool is a method which allows an immediate qualitative conclusion about the patency of an anastomosis. Is it also able to predict the outcome of potentially compromised vascular free flaps?
  
  
  METHODS
  An epigastric flap was raised and repositioned in 79 rats. Intraoperative fluorescence angiography was performed using ICG videoangiography and the FLOW®800 tool was applied. Six regions of interest were positioned systematically over the flap, changes of the ICG fluorescence were color coded with respect to time and 474 measurements were performed. The flap was clinically monitored for one week and the resulting necrotic areas were correlated with the ICG/FLOW®800 results.
  
  
  RESULTS
  Mean intensity of clinically vital areas was 83.39 ± 50.96 arbitrary units (AU) and 37.33 ± 15.14 AU in necrotic areas. The receiver operating characteristic curve and Youden-Index analysis revealed that the optimal cutoff for the maximal intensity of ICG after FLOW®800 analysis was ≤ 61.733 for the prediction of flap necrosis and > 61.733 for the prediction of flap survival (P < 0.0001; 95% CI = 0.85-0.91; Youden-Index: 0.67). The maximal intensity of ICG angiography had a specificity of 96.1% and sensitivity of 71.4%. The positive predictive value was 97.46% and the corresponding negative predictive value was 61.34%.
  
  
  CONCLUSIONS
  This demonstrates the potential additional value of ICG videoangiography including FLOW®800 analyses in the postoperative monitoring of transplanted flaps. © 2016 Wiley Periodicals, Inc. Microsurgery 37:235-242, 2017.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Klinikum Rechts Der Isar, Technische Universität München, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Mücke
authors.affiliation: Department of Oral and Maxillofacial Surgery, Klinikum Rechts Der Isar, Technische Universität München, Germany.
authors.forename: Andreas M
authors.initials: AM
authors.lastname: Fichter
authors.affiliation: Department of Oral and Maxillofacial Surgery, Klinikum Rechts Der Isar, Technische Universität München, Germany.
authors.forename: Leonard H
authors.initials: LH
authors.lastname: Schmidt
authors.affiliation: Department of Oral and Maxillofacial Surgery, Klinikum Rechts Der Isar, Technische Universität München, Germany.
authors.forename: David A
authors.initials: DA
authors.lastname: Mitchell
authors.affiliation: Department of Oral and Maxillofacial Surgery, Klinikum Rechts Der Isar, Technische Universität München, Germany.
authors.forename: Klaus-Dietrich
authors.initials: KD
authors.lastname: Wolff
authors.affiliation: Department of Oral and Maxillofacial Surgery, Klinikum Rechts Der Isar, Technische Universität München, Germany.
authors.forename: Lucas M
authors.initials: LM
authors.lastname: Ritschl
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D019074:Epigastric Arteries / Q000601:surgery; D005451:Fluorescein Angiography / Q000379:methods*; D006084:Graft Rejection; D007208:Indocyanine Green; D008297:Male; D008866:Microsurgery / Q000009:adverse effects / Q000379:methods; D009336:Necrosis / Q000000981:diagnostic imaging / Q000473:pathology; D011237:Predictive Value of Tests; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D018709:Statistics, Nonparametric; D013524:Surgical Flaps / Q000009:adverse effects* / Q000098:blood supply*; D014741:Video Recording
chemical_list: D007208:Indocyanine Green