Current status and future perspective of confocal laser endomicroscopy

Confocal laser endomicroscopy enables in vivo microscopic observation during ongoing endoscopy by using the fluorescent confocal imaging technique. There have been endoscopy-based, probe-based, and needle-based confocal laser endomicroscopes, but the endoscopy-based scope is no longer available. Probe- and needle-based confocal laser endomicroscopy can be applied to various organs such as the biliary and pancreatic ducts, liver, bronchial tubes and alveoli, urinary bladder, and thyroid gland. Fluorescent agents can be administered in two ways including intravenous injection and intraluminal spraying. Confocal laser endomicroscopy enables not only microscopic observation but also functional and molecular imaging. In this article, we describe the mechanism of confocal laser endomicroscopy, its specifications, observation method, and characteristics, and introduce various fields of application in addition to actual images.