A flexible tube of an outer diameter of several millimeters or
thinner, inserted in the body to carry out measurement or simple treatment.
Catheters are used for measuring blood pressure or flow rate,
sampling or removing body fluid or blood, and infusing drug. It is required to manipulate one end
of a catheter placed outside the body and have the inside working end to go through complicatedly
wound part and reach the target point. To facilitate this manipulation, catheters are required to
have appropriate flexibility and rigidity, so they are made of polymer materials. Active catheters
having a working end that can be controlled freely by the operator have also been developed. Some
catheters have a balloon or a cutter on working end with which narrowed blood vessels can be
surgically extended. The field of application is extending because surgical operations with the use
of catheters are less invasive to the patient compared to the conventional method.
Active catheter, Fiber endoscope