Time gated fluorescence spectroscopy in Barrett's oesophagus

Area of Science:

• Gastroenterology
• Endoscopic imaging
• Oncology

Background:

• Barrett's esophagus carries a risk of dysplasia and cancer.
• Standard endoscopy struggles to differentiate specialized intestinal metaplasia (SIM) from dysplasia.
• Early cancer detection in Barrett's esophagus is crucial.

Purpose of the Study:

• To evaluate laser-induced protoporphyrin IX (PpIX) fluorescence for detecting SIM and dysplasia during endoscopy.
• To guide biopsies more accurately, moving beyond random sampling.
• To assess if this method can differentiate SIM from non-dysplastic Barrett's mucosa.

Main Methods:

• 5-aminolaevulinic acid was administered to 53 Barrett's esophagus patients.
• Delayed fluorescence of PpIX was measured in vivo to guide targeted biopsies.
• Biopsy specimens underwent pathological review, including p53 expression analysis.

Main Results:

• Significant differences in fluorescence intensity were observed between non-dysplastic SIM and low-grade dysplasia (p<0.005).
• Dysplasia detection rates increased 2.8-fold with fewer biopsies compared to standard screening.
• Three early-stage cancers were identified, and SIM was differentiated from other esophageal epithelia (p<0.013).

Conclusions:

• Laser-induced PpIX fluorescence endoscopy successfully differentiated low-grade dysplasia from non-dysplastic Barrett's mucosa.
• This technique enhances the detection of specialized intestinal metaplasia, even in short-segment Barrett's esophagus.
• The method allows for guided biopsies, improving diagnostic yield during endoscopy.