Oxygen‐dependent delayed fluorescence of protoporphyrin IX measured in the stomach and duodenum during upper gastrointestinal endoscopy. Issue 10 (20th June 2019)

• Record Type: Journal Article
• Authors: van Dijk, Louisa J. D.; Ubbink, Rinse; Terlouw, Luke G.; van Noord, Desirée; Mik, Egbert G.; Bruno, Marco J.
• Is Part Of: Journal of biophotonics. Volume 12:Issue 10(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-06-20
• Subjects: 5‐aminolevulinic acid (ALA) -- chronic mesenteric ischemia -- COMET -- diagnostics -- oxygen tension (PO2) -- PpIX‐TSLT -- upper gastrointestinal endoscopy; Photonics -- Periodicals; Optical materials -- Periodicals; Optics -- Periodicals; Medical instruments and apparatus -- Periodicals; 621.3605
• DOI: 10.1002/jbio.201900025
• Languages: English
• ISSNs: 1864-063X

Abstract

Abstract: Protoporphyrin IX‐triplet state lifetime technique (PpIX‐TSLT) is a method used to measure oxygen (PO2 ) in human cells. The aim of this study was to assess the technical feasibility and safety of measuring oxygen‐dependent delayed fluorescence of 5‐aminolevulinic acid (ALA)‐induced PpIX during upper gastrointestinal (GI) endoscopy. Endoscopic delayed fluorescence measurements were performed 4 hours after oral administration of ALA in healthy volunteers. The ALA dose administered was 0, 1, 5 or 20 mg/kg. Measurements were performed at three mucosal spots in the gastric antrum, duodenal bulb and descending duodenum with the catheter above the mucosa and while applying pressure to induce local ischemia and monitor mitochondrial respiration. During two endoscopies, measurements were performed both before and after intravenous administration of butylscopolamine. Delayed fluorescence measurements were successfully performed during all 10 upper GI endoscopies. ALA dose of 5 mg/kg showed adequate signal‐to‐noise ratio (SNR) values >20 without side effects. All pressure measurements showed significant prolongation of delayed fluorescence lifetime compared to measurements performed without pressure ( P < .001). Measurements before and after administration of butylscopolamine did not differ significantly in the duodenal bulb and descending duodenum. Measurements of oxygen‐dependent delayed fluorescence of ALA‐induced PpIX in the GI tract during upper GI endoscopy are technically feasible and safe. Abstract : Oxygen tension (PO2 ) can be measured in human cells by delayed fluorescence lifetime quenching of 5‐aminolevulinic acid‐induced protoporphyrin IX. This study aimed to assess the technical feasibility and safety of this technique during upper gastrointestinal endoscopy in the gastrointestinal (GI) tract. The endoscopic delayed fluorescence lifetime measurements in the GI tract were technically feasible and safe. Local mucosal ischemia was introduced temporarily by applying pressure with the probe on the mucosa. The lifetime prolongation demonstrated the oxygen‐dependence of the signal.