Catheter

特許 係属中 In medicine, a catheter /ˈkæθɪtər/ is a thin tube extruded from medical grade materials serving a broad range of functions. Catheters are medical devices that can be inserted in the body to treat diseases or perform a surgical procedure. By modifying the material or adjusting the way catheters are manufactured, it is possible to tailor catheters for cardiovascular, urological, gastrointestinal, neurovascular, and ophthalmic applications. Catheters can be inserted into a body cavity, duct, or vessel. Functionally, they allow drainage, administration of fluids or gases, access by surgical instruments, and also perform a wide variety of other tasks depending on the type of catheter.[1] The process of inserting a catheter is catheterization. In most uses, catheter is a thin, flexible tube ("soft" catheter) though catheters are available in varying levels of stiffness depending on the application. A catheter left inside the body, either temporarily or permanently, may be referred to as an indwelling catheter. A permanently inserted catheter may be referred to as a permcath (originally a trademark) The ancient Syrians created catheters from reeds. "Katheter — καθετήρ" originally referred to an instrument that was inserted such as a plug. The word "katheter" in turn came from "kathiemai — καθίεμαι" meaning "to sit". The ancient Greeks inserted a hollow metal tube through the urethra into the bladder to empty it and the tube came to be known as a "katheter".