It can really cure diseases! \x0d\Leech: A "medical device" with a long history\x0d\For many people, leeches may be creepy and avoidable creatures. But as early as thousands of years ago, people began to try to use it to treat diseases. Ancient Western doctors believed that diseases that make skin reddened were caused by too much blood in the human body, so blood-sucking leeches became a means of treating these diseases. Of course, this theory has no scientific basis. With the advancement of medicine in modern times, leeches have gradually faded out of the medical community. \x0d\But by the 1960s, interest in medical leeches revived. Two Slovenian doctors discovered that leeches can play an auxiliary therapeutic role in preventing congestion during skin flap transplantation [1]. In 1985, plastic surgeon Joseph Upton used a similar method on a little boy's ear replantation surgery and achieved good results. Medical leeches were approved by the FDA as a medical device in 2004, and they continue to be used in hospitals around the world. \x0d\What are medical leeches used for? \x0d\The leech medical case reported in the New England Journal of Medicine is an ear replantation surgery case. A 19-year-old woman was bitten by a pit bull and suffered a broken left ear. Doctors replanted the broken ear through microvascular anastomosis. The operation connected the arterial branches on the ear, but could not find a suitable vein for anastomosis. Although connected arteries can bring oxygen and nutrients, if the veins are not connected, the stagnant blood in place can easily form thrombus, causing tissue hypoxia and necrosis. At this time, the doctor found medical leeches and used them to drain blood and suck away the congestion that could not be transported away by veins. Although leeches cannot truly replace the role of veins, they can reduce the impact of congestion on replanted tissues and buy time for the body to repair its blood supply system. \x0d\Leech saliva contains hirudin, which is a very effective anticoagulant that can directly inhibit thrombin necessary for the blood coagulation process in the body. If you are accidentally bitten by a leech, this substance will cause a lot of trouble in stopping the bleeding. However, when used as a venous drainage, this becomes an advantage: it prevents thrombosis and avoids blood vessel blockage. \x0d\\x0d\Leech-assisted treatment for patients with ear reimplantation. \x0d\In addition, some studies are exploring other medical uses of leeches, such as relieving pain caused by osteoarthritis. Hirudin itself can also be used as an anticoagulant. \x0d\Effective, but also risky\x0d\At some point, medical leeches can indeed be a doctor's best friend. However, using them is also risky. Compared with surgical instruments, even specially cultured medical leeches are not so clean and sterile, so using them to treat wounds involves a certain risk of infection (such as Aeromonas hydrophila infection), and antibiotics are often required when used. to prevent infection. In addition, using living leeches for treatment may also cause adverse reactions such as bleeding and allergies.