title: Sentinel Node Biopsy for the Head and Neck Using Contrast-Enhanced Ultrasonography Combined with Indocyanine Green Fluorescence in Animal Models: A Feasibility Study.
abstract: BACKGROUND
  Sentinel node navigation surgery is gaining popularity in oral cancer. We assessed application of sentinel lymph node navigation surgery to pharyngeal and laryngeal cancers by evaluating the combination of contrast-enhanced ultrasonography and indocyanine green fluorescence in animal models.
  
  
  METHODS
  This was a prospective, nonrandomized, experimental study in rabbit and swine animal models. A mixture of indocyanine green and Sonazoid was used as the tracer. The tracer mixture was injected into the tongue, larynx, or pharynx. The sentinel lymph nodes were identified transcutaneously by infra-red camera and contrast-enhanced ultrasonography. Detection time and extraction time of the sentinel lymph nodes were measured. The safety of the tracer mixture in terms of mucosal reaction was evaluated macroscopically and microscopically.
  
  
  RESULTS
  Sentinel lymph nodes were detected transcutaneously by contrast-enhanced ultrasonography alone. The number of sentinel lymph nodes detected was one or two. Despite observation of contrast enhancement of Sonazoid for at least 90 minutes, the number of sentinel lymph nodes detected did not change. The average extraction time of sentinel lymph nodes was 4.8 minutes. Indocyanine green fluorescence offered visual information during lymph node biopsy. The safety of the tracer was confirmed by absence of laryngeal edema both macro and microscopically.
  
  
  CONCLUSIONS
  The combination method of indocyanine green fluorescence and contrast-enhanced ultrasonography for detecting sentinel lymph nodes during surgery for head and neck cancer seems promising, especially for pharyngeal and laryngeal cancer. Further clinical studies to confirm this are warranted.
authors.affiliation: Department of Head and Neck Surgery, Otolaryngology, Saitama Medical University International Medical Center, Hidaka, Saitama, Japan; Department of Otolaryngology, Head and Neck Surgery, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Yasunao
authors.initials: Y
authors.lastname: Kogashiwa
authors.affiliation: Department of Pharmacology and Toxycology, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Sakurai
authors.affiliation: Department of Anatomy, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Akimoto
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Dai
authors.initials: D
authors.lastname: Sato
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ikeda
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Matsumoto
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Yorihisa
authors.initials: Y
authors.lastname: Moro
authors.affiliation: Department of Pharmacology and Toxycology, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Kimura
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Hamanoue
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Takehiro
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Yamauchi
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Saito
authors.affiliation: Department of Head and Neck Surgery, Otolaryngology, Saitama Medical University International Medical Center, Hidaka, Saitama, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Sugasawa
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Kohno
mesh_terms: D000818:Animals; D003287:Contrast Media; D004195:Disease Models, Animal; D005240:Feasibility Studies; D005290:Ferric Compounds; D005453:Fluorescence; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D007208:Indocyanine Green / Q000378:metabolism*; D007501:Iron; D008198:Lymph Nodes / Q000473:pathology / Q000648:ultrastructure; D008297:Male; D010087:Oxides; D011817:Rabbits; D015203:Reproducibility of Results; D021701:Sentinel Lymph Node Biopsy; D034421:Sus scrofa; D013997:Time Factors; D014463:Ultrasonography
chemical_list: D003287:Contrast Media; D005290:Ferric Compounds; D010087:Oxides; C069727:Sonazoid; D007501:Iron; D007208:Indocyanine Green