If an examination reveals fluid flowing from the nipple, does that necessarily require surgical treatment? This is not necessarily the case, nipple overflow is very common, the presence of nipple overflow does not always have to be a problem, but if it is a single breast single hole bloody overflow, we need to be alerted. The traditional treatment for this condition has been surgical removal of the overflowing milk duct. Now that we have lactoscopy, we can clearly visualize the lesion in the milk duct and avoid surgery if there is not a tumor in the duct. If the bleeding is really caused by a tumor in the milk duct, then the location of the overflowing milk duct and the depth of entry into the scope can be accurately located, locating the lesion in a much smaller area, even though the surgery is more minimally invasive than traditional surgery. It can be said that the clinical application of lactoscopy has greatly improved the etiological diagnosis of patients with nipple overflow and reduced unnecessary surgical biopsies. In addition, ductoscopy can be used for irrigation. For some patients with breast pain caused by milk accumulation in the ducts, they used to need long-term medication or physiotherapy to relieve the pain, but now we use ductoscopic irrigation to treat this part of patients with breast pain.