Bougienage is a therapeutic technique that expands the stenotic or obstructed part of the esophagus through mechanical means. It is widely used in the treatment of diseases such as esophageal stenosis, achalasia of the cardia, and anastomotic stenosis after surgery. Its core principle is to restore the normal inner diameter of the esophagus through progressive dilation, thereby improving the patient's swallowing function. In traditional methods, rigid bougies are used, while modern techniques mostly adopt balloon dilation catheters, which are operated in a more precise and minimally invasive way under the guidance of an endoscope.