Abstract
Confocal endomicroscopy is a newly developed tool that we can use to observe the GI tract mucosa, and it provides subcellular resolution during ongoing endoscopy. Magnifying endoscopy has recently spread to clinical practice, and this super magnifying endoscopy - - confocal endomicroscopy - - is thought to connect magnifying endoscopy with histology. We can inspect cross-sectional images at a depth of from 0 to 250μm deep with a microscopic field of 475μm×475μm. Using confocal endomicroscopy, we can observe both the surface and the subsurface of cellular and microvessel architecture in the gastrointestinal mucosa after the venous administration of fluorescein sodium. For distinguishing between malignant and benign lesions, we should assess the number of cells, the arrangement of glands, the regularity of glands, the size of microvessels, the diameter of microvessels, and the regularity of microvessels. We can also diagnose the malignant change in inflammatory disease of the GI tract, for example ulcerative colitis or Barrett′s esophagus. Although confocal endomicroscopy has disadvantages such as the inability to observe the nucleus in the living cell or allergy to fluorescein, this modality has great potential for providing breakthroughs in the diagnosis of malignancy or in observing physiological molecular movement in the upcoming era of NOTES (Natural Orifice Tansluminal Endoscopic Surgery) or molecular imaging.
