title: Intraoperative combined color and fluorescent images-based sentinel node mapping in the porcine lung: comparison of indocyanine green with or without albumin premixing.
abstract: OBJECTIVE
  We developed a multimodal optical imaging system for intraoperative visualization of sentinel lymph nodes (SLNs). This study is to validate our system by showing SLNs in the lung through combined optical color and fluorescent image with indocyanine green (ICG) and ICG with human serum albumin (HSA).
  
  
  METHODS
  Identical ICG concentrations of ICG only or ICG:HSA was injected into the rat footpad and porcine lung. Absolute amounts of the fluorescents were scaled on the basis of animal weights. The entire procedures were recorded using color and near-infrared (NIR) charge-coupled device (CCD) cameras simultaneously, and the 2 images were merged by real-time image processing software. All fluorescence intensity signals to background ratio (SBR) and retention rates at SLN for both fluorescents were estimated and compared.
  
  
  RESULTS
  This newly developed intraoperative color and fluorescence optical imaging system successfully visualized the SLNs in animal experiments. The SLNs were identified 100% for both rat and pig under in vivo conditions. Real-time image processing software overcame the low signal of NIR fluorescence images. ICG and ICG:HSA provided no significantly different SBR in the SLN images for both rat thigh and pig lung.
  
  
  CONCLUSIONS
  The intraoperative optical imaging system enabled real-time image-guided surgery during SLN mapping in lung in an animal model. The ICG retention rate was similar to ICG:HSA. ICG alone can be useful for SLN imaging during lung cancer surgery.
authors.affiliation: Department of Biomedical Engineering, Korea University, Seoul, Korea.
authors.forename: Yujin
authors.initials: Y
authors.lastname: Oh
authors.forename: Yu Hua
authors.initials: YH
authors.lastname: Quan
authors.forename: Yeonho
authors.initials: Y
authors.lastname: Choi
authors.forename: Choong Ki
authors.initials: CK
authors.lastname: Kim
authors.forename: Heezoo
authors.initials: H
authors.lastname: Kim
authors.forename: Hyun Koo
authors.initials: HK
authors.lastname: Kim
authors.forename: Beop-Min
authors.initials: BM
authors.lastname: Kim
mesh_terms: D000818:Animals; D003116:Color; D005260:Female; D005453:Fluorescence; D005456:Fluorescent Dyes; D007090:Image Interpretation, Computer-Assisted; D007208:Indocyanine Green; D007430:Intraoperative Care; D008168:Lung / Q000473:pathology* / Q000601:surgery; D008198:Lymph Nodes / Q000473:pathology*; D023421:Models, Animal; D064847:Multimodal Imaging / Q000379:methods*; D061848:Optical Imaging / Q000379:methods*; D011237:Predictive Value of Tests; D051381:Rats; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*; D012709:Serum Albumin; D000075462:Serum Albumin, Human; D012984:Software; D013552:Swine
chemical_list: C422455:ALB protein, human; D005456:Fluorescent Dyes; D012709:Serum Albumin; D007208:Indocyanine Green; D000075462:Serum Albumin, Human
keywords: 10.4; 9; CCD; HSA; ICFIS; ICG; NIR; SBR; SLN; charge-coupled device; human serum albumin; indocyanine green; intraoperative color and fluorescence imaging system; near-infrared; sentinel lymph node; signal to background ratio