A ureteral stent includes an elongate member defining an axis and having a proximal end portion and a distal end portion. An inspection system 20 comprises a sensor chip 1 including plural sensor elements, a computer 21, probes 22 for supplying an inspection signal to circuit wirings 101, and a selector 23 for switching the supply of the inspection signal to the probes 22. The illumination homogenizing optical element is advantageous over prior art illumination homogenizing optical elements in that it is easy and inexpensive to manufacture while providing sufficient optical performance. A permanent magnet motor is connected to the worm. The knife is configured to allow the blade to be in retracted and extended positions when the first and second handle members are in either the unfolded or folded positions.