MICRO-INJECTION PUMP

摘要

A micro-injection pump (10) for angiography and micro-intervention procedures comprises first and second linear traverses (12, 14) each having a pusher element (12F, 14F) movable by stepper motor drive (12D, 14D) for controlling discharge from a respective micro-syringe (16, 20) engaged by the pusher element (12F, 14F). The first micro-syringe (16) preferably contains a volume of a soluble contrast medium (18), and the second micro-syringe preferably contains a volume of an insoluble contrast medium (22). Fluid discharged by the micro-syringes (16, 20) is directed to a bifurcated micro-droplet generator (28) having a straight primary passage (30D) and an obliquely merging tributary passage (30E). Insoluble contrast medium (22) from the second micro-syringe (20) flows through a micro-sized injection needle (34) extending partially and coaxially within the primary passage (30D) to a termination point just downstream from where the tributary passage (30E) joins the primary passage (30D). Soluble contrast medium (18) from the first micro-syringe (16) passes through the tributary passage (30E) to provide a flow field surrounding the injection needle (34) for shearing off discrete same-sized boluses (22A) from the terminal tip of the injection needle (34) at regular frequency in coordination with a predetermined motion profile of the first and second linear traverses (12, 14). Motion control of the linear traverses is possible using LABVIE3 virtual instrumentation software arranged to communicate with a 2-axis indexer control (58) connected to first and second motor indexers (46, 50) for driving the stepper motors (12D, 14D) of the linear traverses (12, 14). Linear potentiometers (84, 86) on the linear traverses (12, 14), rotary encoders (85, 87) connected to the motors (12D, 14D), a flowmeter (92), and pressure transducers (88, 90) indicate motion and flow parameters of the system in real-time to provide a feedback loop in the system so that a desired media delivery waveform is realized.