Optical Detection of High-Grade Dysplasia in Barrett’s Esophagus

Autofluorescence endoscopy

Autofluorescence endoscopy is a wide area imaging technique, with the ability to rapidly examine a large surface area of gastrointestinal mucosa to detect small areas of dysplasia or cancer. It has potential in diseases such as Barrett's esophagus, ulcerative colitis, and gastric cancer, in which large areas of mucosa may harbor areas of dysplasia or superficial cancer not visible on conventional or high-definition white-light endoscopy. Autofluorescence endoscopy technology has evolved from fiberoptic to video technology with a marked improvement in image quality. Although fiberoptic autofluorescence endoscopy seems to provide no advantage over conventional white-light imaging, videobased technology, especially if combined with narrow band imaging, offers great promise for enhancing endoscopic surveillance of Barrett's esophagus. However, for this technology to have future clinical applications, image quality still needs to be improved and the false positive rate needs to be decreased further. Autofluorescence technology detects indirect measures of dysplasia and carcinoma, and is nonspecific, so additional enhancements are clearly desirable.

Vibrational spectroscopy: a clinical tool for cancer diagnostics

Vibrational spectroscopy techniques have demonstrated potential to provide non-destructive, rapid, clinically relevant diagnostic information. Early detection is the most important factor in the prevention of cancer. Raman and infrared spectroscopy enable the biochemical signatures from biological tissues to be extracted and analysed. In conjunction with advanced chemometrics such measurements can contribute to the diagnostic assessment of biological material. This paper also illustrates the complementary advantage of using Raman and FTIR spectroscopy technologies together. Clinical requirements are increasingly met by technological developments which show promise to become a clinical reality. This review summarises recent advances in vibrational spectroscopy and their impact on the diagnosis of cancer.

Optical spectroscopy for the detection of dysplasia in Barrett's esophagus

Patients with Barrett's esophagus (BE) undergo periodic endoscopic surveillance with multiple biopsy examinations in an attempt to identify dysplastic and early cancerous lesions at a time when intervention can be beneficial. However, this surveillance approach is hindered by low sampling yield, random sampling error, pathology-associated costs, and delay in diagnosis. Optical spectroscopy offers the potential to identify tissue pathology accurately in real time. The technique uses diagnostic molecular and/or microstructural information contained in light-tissue interactions such as fluorescence, elastic scattering, and inelastic (Raman) scattering. As an adjunct to endoscopy, optical spectroscopy has the capacity to enhance lesion detection in premalignant conditions such as BE. This article highlights the current status and future prospects of optical spectroscopy in BE.