Confocal
laser endomicroscopy (CLE) is an advanced imaging
technique which combines conventional
white light endoscopy (WLE) with an integrated or probe based confocal microscope. This allows microscopic examination of the surface
epithelium and in vivo
diagnosis during
endoscopy. Established CLE applications include the
diagnosis of Barrett’s oesophagus, gastric intestinal
metaplasia, coeliac
disease and
microscopic colitis. CLE can differentiate hyperplastic from
adenomatous polyps in the
colon and may obviate the need to
biopsy all
polyps at
endoscopy. CLE is particularly helpful in
surveillance endoscopy in
inflammatory bowel disease where it has been shown to reduce the number of
biopsies required and improve the
detection of dysplasia. The
future of CLE may be with new
contrast agents to allow for molecular tagging and improved endoscopic
diagnoses. The aim of this
review is to describe the
technology and
techniques involved in CLE, and discuss the evolving applications in obtaining “virtual
biopsy” throughout the
GI tract.