Confocal laser endomicroscopy (CLE) is a new endoscopic imaging technology that allows real-time, high-resolution observation of tomographic images of mucosal cells and subcellular levels in vivo , detecting microscopic structural changes in mucosal morphology, and its in vivo immediate pathological di agnostic capability can avoid delays in mucosal pathological diagnosis and reduce the pain caused by repeated biopsies. CLE is known as “ optical biopsy ” and compared with other endoscopic techniques, it has obvious advantages. CLE systems include probe-based confocal laser endomicroscopy (pCLE) and endoscope-based confocal laser endomicroscopy (eCLE). Since 2006, CLE has been widely used for the evaluation of various lesions in the digestive system, including esophageal, gastric, and colonic neoplasia, pancreatic cysts and solid lesions, and inflammatory bowel disease. The advent of CLE has made in vivo microscopic imaging possible, which has changed the endoscopic screening and diagnosis of multiple gastrointestinal (GI) lesions. However, the value of its use in GI diseases is still controversial. In this review, we focus on the application of CLE in the field of esophageal diseases.
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