Scope of application of lactoductoscopy The main indication is breast diseases with nipple overflow as a clinical manifestation. From the aspect of nipple overflow etiology, nipple overflow can be divided into physiological and pathological. Common physiological nipple overflow includes nipple overflow during pregnancy, milk secretion during lactation, nipple overflow caused by hormonal changes before and after menopause, nipple overflow caused by mechanical stimulation of the mammary nipple, and nipple overflow of unknown origin. Common pathological nipple discharge includes: nipple discharge caused by breast diseases, nipple discharge may occur in breast ductal epithelial hyperplasia, inflammation, hemorrhage, necrosis and tumors and other lesions. From the clinical statistics, the proportion of nipple discharge caused by breast diseases are, in descending order: intraductal papilloma of the breast (40%), cystic hyperplasia of the breast (25%), ductal dilatation of the breast (10%-15%), breast cancer (5%-10%), mastitis, and fibroadenoma of the breast. It should be noted that not all breast diseases can cause nipple discharge, such as about 80% of patients with intraductal papilloma (disease) can develop nipple discharge, while breast cancer patients have a lower chance of developing nipple discharge (about 5%); nipple discharge caused by non-breast diseases, including pituitary tumors, drugs or nearby intracranial tumors interfering with endocrine function of the hypothalamus, hyper- or hypothyroidism, chronic liver disease and so on. , chronic liver disease, etc. Diagnostic value of lactoductoscopy Since the vast majority of breast diseases originate in the milk ducts, lactoductoscopy is of great clinical value in the diagnosis and treatment of breast diseases. The clinical application value of lactoductoscopy has been clearly defined as a necessary means of diagnosing nipple discharge disease, which has unparalleled advantages over other examination methods. Breast ductoscopy can carry out multifaceted screening and diagnosis of breast diseases through intuitive endoscopic image-assisted localization of the breast ducts, pathological examination of tumor indicators and exfoliated cells of the flushing fluid, histopathological examination of biopsy of the elevated lesions, etc., which helps to discover early lesions in the ducts of the breast. Mammoscopy can directly enter the diseased milk ducts for intuitive endoscopic examination, and the images it provides include the contents of the milk ducts, the wall of the milk ducts, and the bulging lesions in the milk ducts, which is of great significance for the diagnosis of diseases in the milk ducts. At present, the breast diseases and their manifestations diagnosed by lactoductoscopy are mainly: (1) Intraductal papillomas of the breast, including solitary papillomas, multiple papillomas and papillomatosis. (2) Dilatation of the mammary ducts. (3) Inflammation of the breast ducts (4) Intraductal carcinoma. The diagnosis of diseased milk ducts can be aided by localization through lactoductoscopy. Through the direction and depth of the nipple and breast gland, it can determine the lesion ducts, depth and scope, and roughly determine the lesion’s surface localization, and at the same time, it can be accurately diagnosed through the dye and localization of the guide wire, which can provide important reference information for the surgical and pathological examination; on the other hand, lactoductal microscopy can also provide ultrasound, coarse needle puncture biopsy and other examinations with more accurate information of the lesion’s location, nature and scope, and so on. Information. Some of the contents of the milk ducts, including the proteins and exfoliated cells in the overflow, can be obtained through lactoductoscopy, and the detection of the components of these flushes can provide an important basis for the diagnosis of certain breast diseases, especially for malignant tumors. The currently developed mastectomy tissue biopsy can directly obtain the lesion tissue, carry out pathological examination, clear diagnosis, and has diagnostic significance. However, it cannot completely replace surgical excision biopsy. As a new endoscopic technology with the advantages of minimally invasive and intuitive that other endoscopes have, lactoductoscopy can be applied to preoperative auxiliary biopsy for certain breast diseases other than those manifested by nipple overflow. Therapeutic value of lactoductoscopy In terms of clinical therapeutic application of lactoductoscopy, in addition to assisting in localizing the diseased milk ducts for surgical resection, there are many new explorations, resulting in a lot of new clinical application value. The value of lactoductoscopy in assisting in localizing the diseased milk ducts for surgical excision has been relatively clear, with the advantages of precise localization, low leakage rate, small surgical damage, and cosmetic appearance. It has been routinely carried out in most breast surgeries in China that have the technology of lactoductoscopy.