The system includes a stand surrounding a working area, a signal detector receiving a signal generated by the wire, and a positioning module disposed on the stand. The positioning module is configured to drive the signal detector moving forward and backward on a two-dimensional plane in the working area. The system also includes a computer system electrically connected to the signal detector and the positioning module. The compute system receives the signal from the signal detector, generates position information according to the signal, and transmits the position information to the positioning module, such that the positioning module moves the signal detector to a position corresponding to a position of the wire in the blood vessel according to the position information.