title: Multispectral characterization of tissues encountered during laparoscopic colorectal surgery.
abstract: OBJECTIVE
  This study investigated the feasibility of automated differentiation between essential tissue types encountered during laparoscopic colorectal surgery using spectral analysis.
  
  
  METHODS
  Wide band (440-1830 nm) spectra were collected using an optical fiber probe and spectrometer from freshly explanted, ex vivo, human colonic specimens. These data were normalized at 810 nm (an isobestic wavelength for hemoglobin and oxy-hemoglobin) and mathematically analyzed using total principal component regression (TPCR).
  
  
  RESULTS
  929 spectra were collected from specimens of 19 patients, distinguishing 5 tissue types: mesenteric fat (MF, n=269), blood vessels (BV, n=377), colonic tissue (CT, n=213), ureter (UR, n=10) and tumorous tissue in colon (TT, n=60). For each individual tissue type the distinctive ability was determined against all other tissue types pooled as a group. Paired probability density function (PDF) of "tissue" (centered around label 1) versus "all other pooled tissues" (centered around label 0) and the cumulative distribution function (CDF) at label crossover value 0.5 was determined for each tissue type (MF: CDF=0.99 [SD=0.19]; BV: CDF=0.95 [SD=0.29]; CT: CDF=0.98 [SD=0.22]; UR: CDF=0.99 [SD=0.09]; TT: CDF=0.99 [SD=0.18]).
  
  
  CONCLUSIONS
  Automated spectral differentiation of blood vessel, ureter, mesenteric adipose tissue, colonic tissue and tumorous tissue in colon, is feasible in freshly explanted human colonic specimens. These results may be exploited for further steps toward multi- or hyperspectrally enhanced in vivo (laparoscopic) surgical imaging.
authors: Department of Surgery, Maastricht University Medical Center, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands. rutgermschols@hotmail.com
authors: Rutger M
authors: RM
authors: Schols
authors: Par
authors: P
authors: Dunias
authors: Fokko P
authors: FP
authors: Wieringa
authors: Laurents P S
authors: LP
authors: Stassen
mesh_terms: D000328:Adult; D000368:Aged; D003106:Colon / Q000098:blood supply / Q000166:cytology*; D005260:Female; D006801:Humans; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D057054:Molecular Imaging / Q000295:instrumentation / Q000379:methods*; D055100:Optical Fibers; D009928:Organ Specificity; D013057:Spectrum Analysis; D055815:Young Adult