Abstract: The present invention relates to a seal for a rotatable therapeutic catheter, such as a motor driven therapeutic catheter. The seal is made of a drive shaft which extends through an elongated bushing. The combined drive shaft and bushing form a low-friction axle/bearing combination such that there is little friction between them. In addition, the long restrictive path between the drive shaft and the bushing serves to prevent leakage between them.

Abstract: The present invention is a pump apparatus which is adapted to move liquids which contain debris. The apparatus is adapted to operate by alternating suction and pressure, whereby any debris which becomes lodged in any orifices or conduits in the system is effectively dislodged as a consequence of the normal operation of the system.The push-pull material transport system of the present invention includes a conduit to transport fluid from a first location to another location. The invention includes a peristaltic pump which has two heads. The first head pumps fluid from the first location to the second location, and the second head intermittently and periodically pumps fluid in the reverse direction in order to keep the conduit clear of debris.