A system and method for collection and re-use of a fluid medium derived from the diversion of at least some of an injection of the medium to a selected site within a patient's body are described. The system includes a sterile medium container, a flow diverter assembly disposed in a fluid medium flow path between an injection syringe and a medium delivery catheter, and a diversion reservoir having a reservoir chamber for receiving the diverted portion of the fluid medium from the flow diverter assembly and a fluid coupling to the sterile medium container. The flow diverter assembly is configured to divert at least a portion of a fluid medium injection from the medium flow path between the syringe and the delivery catheter during injection. The diversion reservoir is configured so as to preferentially allow re-use of the diverted medium in the reservoir chamber prior to allowing use of the medium in the sterile medium container.
