title: Technical feasibility of visualizing myenteric plexus using confocal laser endomicroscopy.
abstract: OBJECTIVE
  In preceding studies, we identified that the myenteric plexus (MP) could be visualized with confocal laser endomicroscopy (CLE) by applying neural fluorescent probes lacking clinical safety profiling data from the submucosal side. In this study, we evaluated the technical feasibility of MP visualization using probe-based CLE (pCLE) from the serosal side with cresyl violet (CV), which has been used clinically for chromoendoscopy.
  
  
  METHODS
  The dye affinity of CV for MP was first explored in an in vivo transgenic mouse model using neural crest derivatives labeled with green fluorescent protein. We also tested the feasibility of CV-assisted visualization of MP in human surgical specimens, wherein the tissue dying and pCLE observation were performed from the serosal side. In the human study, rate of MP visualization by pCLE was evaluated as the primary outcome. We also evaluated the sensitivity and specificity of MP visualization by pCLE, using pathological presence/absence of MP as the gold standard.
  
  
  RESULTS
  We confirmed the dye affinity of CV to MP in all tested models. The MP appeared as brightly stained ladder-like structures with pCLE, and in the human study, MP was visualized in 12/14 (85.7%) samples, with 92.3% sensitivity and 100% specificity. In positive cases showing the ladder-like structure of MP by pCLE, the mean maximum and minimum widths of nerve strands were 54.3 (± 23.6) and 19.7 (± 6.0) μm, respectively. A ganglion was detected by pCLE in 10 cases (10/12, 83.3%).
  
  
  CONCLUSIONS
  This study demonstrated the technical feasibility of visualizing the MP in real time by CV-assisted pCLE (UMIN-CTR number, UMIN000015056).
authors.affiliation: Department of Endoscopy and Division of Gastroenterology and Hepatology, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan.
authors.forename: Masakuni
authors.initials: M
authors.lastname: Kobayashi
authors.affiliation: Department of Endoscopy, The Jikei University School of Medicine, Tokyo, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Sumiyama
authors.affiliation: Department of Pediatric Surgery, Keio University School of Medicine, Tokyo, Japan.|Department of Surgery, Tokyo Metropolitan Children's Medical Center, Tokyo, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Shimojima
authors.affiliation: Department of Pediatric Surgery, Kagoshima University, Kagoshima, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ieiri
authors.affiliation: Department of Physiology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Okano
authors.affiliation: Department of Endoscopy and Division of Gastroenterology and Hepatology, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Kamba
authors.affiliation: Department of Pediatric Surgery, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Takumi
authors.initials: T
authors.lastname: Fujimura
authors.affiliation: Department of Surgery, Tokyo Metropolitan Children's Medical Center, Tokyo, Japan.
authors.forename: Seiichi
authors.initials: S
authors.lastname: Hirobe
authors.affiliation: Department of Pediatric Surgery, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Kuroda
authors.affiliation: Department of Neuropathology, Brain Bank for Aging Research, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Takahashi-Fujigasaki
mesh_terms: D000293:Adolescent; D000818:Animals; D048588:Benzoxazines; D002648:Child; D002675:Child, Preschool; D005240:Feasibility Studies; D005260:Female; D005456:Fluorescent Dyes; D049452:Green Fluorescent Proteins; D006801:Humans; D007223:Infant; D008297:Male; D008822:Mice, Transgenic; D018613:Microscopy, Confocal / Q000379:methods*; D023421:Models, Animal; D009197:Myenteric Plexus / Q000648:ultrastructure*
chemical_list: D048588:Benzoxazines; D005456:Fluorescent Dyes; D049452:Green Fluorescent Proteins; C028911:cresyl violet
keywords: clinical pediatric gastroenterology; endoscopy: colon; pediatric disorders