title: Endoscopic visible light spectroscopy: a new, minimally invasive technique to diagnose chronic GI ischemia.
abstract: BACKGROUND
  The diagnosis of chronic GI ischemia (CGI) remains a clinical challenge. Currently, there is no single simple test with high sensitivity available. Visible light spectroscopy (VLS) is a new technique that noninvasively measures mucosal oxygen saturation during endoscopy.
  
  
  OBJECTIVE
  To determine the diagnostic accuracy of VLS for the detection of ischemia in a large cohort of patients.
  
  
  METHODS
  Prospective study, with adherence to the Standards for Reporting of Diagnostic Accuracy.
  
  
  METHODS
  Tertiary referral center.
  
  
  METHODS
  Consecutive patients referred for evaluation of possible CGI.
  
  
  METHODS
  Patients underwent VLS along with the standard workup consisting of evaluation of symptoms, GI tonometry, and abdominal CT or magnetic resonance angiography.
  
  
  METHODS
  VLS measurements and the diagnosis of CGI as established with the standard workup.
  
  
  RESULTS
  In 16 months, 121 patients were included: 80 in a training data set and 41 patients in a validation data set. CGI was diagnosed in 89 patients (74%). VLS cutoff values were determined based on the diagnosis of CGI and applied in the validation data set, and the results were compared with the criterion standard, resulting in a sensitivity and specificity of VLS of 90% and 60%, respectively. Repeated VLS measurements showed improvement in 80% of CGI patients after successful treatment.
  
  
  CONCLUSIONS
  Single-center study; only 43% of patients had repeated VLS measurements after treatment.
  
  
  CONCLUSIONS
  VLS during upper endoscopy is a promising easy-to-perform and minimally invasive technique to detect mucosal hypoxemia in patients clinically suspected of having CGI, showing excellent correlation with the established ischemia workup.
authors.affiliation: Department of Gastroenterology and Hepatology, Erasmus Medical Center-University Medical Center, Rotterdam, The Netherlands. d.vannoord@erasmusmc.nl
authors.forename: Désirée
authors.initials: D
authors.lastname: Van Noord
authors.forename: Aria
authors.initials: A
authors.lastname: Sana
authors.forename: David A
authors.initials: DA
authors.lastname: Benaron
authors.forename: Peter M T
authors.initials: PM
authors.lastname: Pattynama
authors.forename: Hence J M
authors.initials: HJ
authors.lastname: Verhagen
authors.forename: Bettina E
authors.initials: BE
authors.lastname: Hansen
authors.forename: Ernst J
authors.initials: EJ
authors.lastname: Kuipers
authors.forename: Peter B F
authors.initials: PB
authors.lastname: Mensink
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D041981:Gastrointestinal Tract / Q000098:blood supply*; D006801:Humans; D007511:Ischemia / Q000175:diagnosis*; D008027:Light; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013057:Spectrum Analysis / Q000379:methods*; D055815:Young Adult