title: In vivo endoluminal ultrasound biomicroscopic imaging in a mouse model of colorectal cancer.
abstract: OBJECTIVE
  The gold-standard tool for colorectal cancer detection is colonoscopy, but it provides only mucosal surface visualization. Ultrasound biomicroscopy allows a clear delineation of the epithelium and adjacent colonic layers. The aim of this study was to design a system to generate endoluminal ultrasound biomicroscopic images of the mouse colon, in vivo, in an animal model of inflammation-associated colon cancer.
  
  
  METHODS
  Thirteen mice (Mus musculus) were used. A 40-MHz miniprobe catheter was inserted into the accessory channel of a pediatric flexible bronchofiberscope. Control mice (n = 3) and mice treated with azoxymethane and dextran sulfate sodium (n = 10) were subjected to simultaneous endoluminal ultrasound biomicroscopy and white-light colonoscopy. The diagnosis obtained with endoluminal ultrasound biomicroscopy and colonoscopy was compared and confirmed by postmortem histopathology.
  
  
  RESULTS
  Endoluminal ultrasound biomicroscopic images showed all layers of the normal colon and revealed lesions such as lymphoid hyperplasias and colon tumors. Additionally, endoluminal ultrasound biomicroscopy was able to detect two cases of mucosa layer thickening, confirmed by histology. Compared to histologic results, the sensitivities of endoluminal ultrasound biomicroscopy and colonoscopy were 0.95 and 0.83, respectively, and both methods achieved specificities of 1.0.
  
  
  CONCLUSIONS
  Endoluminal ultrasound biomicroscopy can be used, in addition to colonoscopy, as a diagnostic method for colonic lesions. Moreover, experimental endoluminal ultrasound biomicroscopy in mouse models is feasible and might be used to further develop research on the differentiation between benign and malignant colonic diseases.
authors.affiliation: Biomedical Engineering Program, COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Kelly Z
authors.initials: KZ
authors.lastname: Alves
authors.forename: Rossana C
authors.initials: RC
authors.lastname: Soletti
authors.forename: Marcelo A P
authors.initials: MA
authors.lastname: de Britto
authors.forename: Dyanna G
authors.initials: DG
authors.lastname: de Matos
authors.forename: Mônica
authors.initials: M
authors.lastname: Soldan
authors.forename: Helena L
authors.initials: HL
authors.lastname: Borges
authors.forename: João C
authors.initials: JC
authors.lastname: Machado
mesh_terms: D000818:Animals; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging*; D004195:Disease Models, Animal; D019160:Endosonography / Q000379:methods*; D004867:Equipment Design; D051379:Mice; D033401:Microscopy, Acoustic / Q000295:instrumentation / Q000379:methods*